Gymnastik- och idrottshögskolan, GIH

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  • 1.
    Andersson, Eva
    et al.
    Gymnastik- och idrottshögskolan, GIH, Institutionen för idrotts- och hälsovetenskap, Laboratoriet för biomekanik och motorisk kontroll (BMC).
    Oddsson, L
    Grundström, H
    Thorstensson, Alf
    Gymnastik- och idrottshögskolan, GIH, Institutionen för idrotts- och hälsovetenskap, Laboratoriet för biomekanik och motorisk kontroll (BMC).
    The role of the psoas and iliacus muscles for stability and movement of the lumbar spine, pelvis and hip.1995Inngår i: Scandinavian Journal of Medicine and Science in Sports, ISSN 0905-7188, E-ISSN 1600-0838, Vol. 5, nr 1, s. 10-6Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The activation patterns of the psoas and iliacus muscles were investigated in 7 healthy adult subjects (4 men and 3 women) during a variety of motor tasks in standing, sitting and lying. Myoelectric activity was recorded simultaneously from the 2 muscles using thin wire electrodes inserted under guidance of high-resolution ultrasound. In general, both muscles were coactivated, albeit to different relative levels, particularly when hip flexor torque was required. Selective activation of the iliacus could, however, be seen to stabilize the pelvis in contralateral hip extension during standing. Psoas was found to be selectively involved in sitting with a straight back and in contralateral loading situations requiring stabilization of the spine in the frontal plane. During training exercises from a supine position, such as sit-ups, the contribution of the psoas and iliacus muscles could be varied by changing the range of motion as well as the position and support for the legs. Thus, the 2 anatomically different muscles of the iliopsoas complex were shown to have individual and task-specific activation patterns depending on the particular demands for stability and movement at the lumbar spine, pelvis and hip.

  • 2.
    Andersson, Helena A
    et al.
    Örebro University, Sweden.
    Bøhn, S K
    Raastad, T
    Paulsen, G
    Blomhoff, R
    Kadi, F
    Differences in the inflammatory plasma cytokine response following two elite female soccer games separated by a 72-h recovery.2010Inngår i: Scandinavian Journal of Medicine and Science in Sports, ISSN 0905-7188, E-ISSN 1600-0838, Vol. 20, nr 5, s. 740-7Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    We investigated changes in a large battery of pro- and anti-inflammatory cytokines in elite female soccer players following two 90-min games separated by a 72-h active or passive recovery. Blood samples were taken from 10 players before, within 15-20 min, 21, 45 and 69 h after the first game and within 15-20 min after the second game. The leukocyte count was analyzed, together with several plasma pro- and anti-inflammatory cytokines, using a multiplex bead array system. After the first and second game, the total leukocytes and neutrophils increased significantly. Likewise, increases (P<0.05) in pro-inflammatory cytokines [interleukin (IL)-12, tumor necrosis factor-α (TNF-α), interferon-γ (INF-γ), IL-17], chemokines [monocyte chemotactic protein-1 (MCP-1), IL-8 and monokine induced by gamma interferon (MIG)], anti-inflammatory cytokines (IL-2R, IL-4, IL-5, IL-7, IL-10, IL-13, INF-α) and the mixed cytokine IL-6 were observed. Leukocyte and cytokine levels were normalized within 21 h. Active recovery (low-intensity exercises) did not affect the cytokine responses. A dampened cytokine response was observed after the second game as only IL-12, IL-6, MCP-1, IL-8 and MIG increased (P<0.05). In conclusion, a robust pro- and anti-inflammatory cytokine response occurs after the first but not the second soccer game. The implications of the dampened cytokine response in female players after the second game are unknown.

  • 3.
    Andersson, Helena A
    et al.
    Örebro University, Sweden.
    Karlsen, A
    Blomhoff, R
    Raastad, T
    Kadi, F
    Plasma antioxidant responses and oxidative stress following a soccer game in elite female players.2010Inngår i: Scandinavian Journal of Medicine and Science in Sports, ISSN 0905-7188, E-ISSN 1600-0838, Vol. 20, nr 4, s. 600-8Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    We aimed to investigate markers of oxidative stress and levels of endogenous and dietary antioxidants in 16 elite female soccer players in response to a 90-min game (average intensity 82+/-3% HRpeak). Blood samples were taken before, immediately and 21 h after the game. Plasma-oxidized glutathione, the ratio of reduced to oxidized glutathione (GSH:GSSG) and lipid peroxidation measured by d-ROMs were used as markers of oxidative stress. Plasma endogenous [uric acid, total glutathione (TGSH)] and dietary antioxidants (alpha-tocopherol, ascorbic acid, total carotenoids and polyphenols) were analyzed using liquid chromatography and the Folin-Ciocalteu method. Exercise induced an acute increase (P<0.05) in GSSG, uric acid, TGSH, alpha-tocopherol, and ascorbic acid. In parallel, the GSH:GSSG ratio and polyphenols decreased (P<0.05). GSSG, GSH:GSSG ratio, uric acid, TGSH, and ascorbic acid returned to baseline at 21 h, while polyphenols and alpha-tocopherol remained altered. Total carotenoids increased above baseline only at 21 h (P<0.05). Lipid peroxidation, measured by d-ROMs, remained unchanged throughout the study. Thus, intermittent exercise in well-trained female athletes induces a transient increase in GSSG and a decrease in the GSH:GSSG ratio, which is effectively balanced by the recruitment of both endogenous and dietary antioxidants, resulting in the absence of lipid peroxidation measured by d-ROMs.

  • 4.
    Arvidsson, Daniel
    et al.
    Center for Health and Performance, Department of Food and Nutrition, and Sport Science, Faculty of Education, University of Gothenburg, Gothenburg, Sweden.
    Fridolfsson, J
    Center for Health and Performance, Department of Food and Nutrition, and Sport Science, Faculty of Education, University of Gothenburg, Gothenburg, Sweden.
    Ekblom Bak, Elin
    Gymnastik- och idrottshögskolan, GIH, Institutionen för fysisk aktivitet och hälsa.
    Ekblom, Örjan
    Gymnastik- och idrottshögskolan, GIH, Institutionen för fysisk aktivitet och hälsa.
    Bergström, G
    Department of Molecular and Clinical Medicine, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden ; Department of Clinical Physiology, Region Västra Götaland, Gothenburg, Sweden..
    Börjesson, Mats
    Center for Health and Performance, Department of Molecular and Clinical Medicine, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden. ; Sahlgrenska University Hospital, Region Västra Götaland, Gothenburg, Sweden..
    Fundament for a methodological standard to process hip accelerometer data to a measure of physical activity intensity in middle-aged individuals.2024Inngår i: Scandinavian Journal of Medicine and Science in Sports, ISSN 0905-7188, E-ISSN 1600-0838, Vol. 34, nr 1, artikkel-id e14541Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    BACKGROUND: There is a lack of a methodological standard to process accelerometer data to measures of physical activity, which impairs data quality and comparability. This study investigated the effect of different combinations of settings of multiple processing components, on the measure of physical activity and the association with measures of cardiometabolic health in an unselected population of middle-aged individuals.

    METHODS: Free-living hip accelerometer data, aerobic fitness, body mass index, HDL:total cholesterol ratio, blood glucose, and systolic blood pressure were achieved from 4391 participants 50-64 years old included in The Swedish CArdioPulmonary bioImage Study (SCAPIS) baseline measurement (cross-sectional). Lab data were also included for calibration of accelerometers to provide comparable measure of physical activity intensity and time spent in different intensity categories, as well as to enhance understanding. The accelerometer data processing components were hardware recalibration, frequency filtering, number of accelerometer axes, epoch length, wear time criterium, time composition (min/24 h vs. % of wear time). Partial least regression and ordinary least regression were used for the association analyses.

    RESULTS: The setting of frequency filter had the strongest effect on the physical activity intensity measure and time distribution in different intensity categories followed by epoch length and number of accelerometer axes. Wear time criterium and recalibration of accelerometer data were less important. The setting of frequency filter and epoch length also showed consistent important effect on the associations with the different measures of cardiometabolic health, while the effect of recalibration, number of accelerometer axes, wear time criterium and expression of time composition was less consistent and less important. There was a large range in explained variance of the measures of cardiometabolic health depending on the combination of processing settings, for example, 12.1%-20.8% for aerobic fitness and 5.8%-14.0% for body mass index.

    CONCLUSIONS: There was a large variation in the physical activity intensity measure and the association with different measures of cardiometabolic health depending on the combination of settings of accelerometer data processing components. The results provide a fundament for a standard to process hip accelerometer data to assess the physical activity in middle-aged populations.

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  • 5.
    Arvidsson, Daniel
    et al.
    University of Gothenburg.
    Fridolfsson, Jonatan
    University of Gothenburg.
    Börjesson, Mats
    University of Gothenburg.
    Andersen, Lars Bo
    Western Norway University of Applied Sciences, Campus Sogndal, Norway..
    Ekblom, Örjan
    Gymnastik- och idrottshögskolan, GIH, Institutionen för idrotts- och hälsovetenskap, Åstrandlaboratoriet.
    Dencker, Magnus
    Lund University.
    Brønd, Jan Christian
    University of Southern Denmark, Odense, Denmark.
    Re-examination of accelerometer data processing and calibration for the assessment of physical activity intensity.2019Inngår i: Scandinavian Journal of Medicine and Science in Sports, ISSN 0905-7188, E-ISSN 1600-0838, Vol. 29, nr 10, s. 1442-1452Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    This review reexamines use of accelerometer and oxygen uptake data for assessment of activity intensity. Accelerometers capture mechanical work, while oxygen uptake captures the energy cost of this work. Frequency filtering needs to be considered when processing acceleration data. A too restrictive filter attenuates the acceleration signal for walking and, to a higher degree, for running. This measurement error affects shorter (children) more than taller (adults) individuals due to their higher movement frequency. Less restrictive filtering includes more movement related signals and provide measures that better capture mechanical work, but may include more noise. An optimal filter cut-point is determined where most relevant acceleration signals are included. Further, accelerometer placement affects what part of mechanical work being captured. While the waist placement captures total mechanical work and therefore contributes to measures of activity intensity equivalent by age and stature, the thigh and wrist placements capture more internal work and do not provide equivalent measures. Value calibration of accelerometer measures is usually performed using measured oxygen uptake with the metabolic equivalent of task (MET) as reference measure of activity intensity. However, the use of MET is not stringent and is not a measure of activity intensity equivalent by age and stature. A candidate measure is the mass-specific net oxygen uptake, VO2 net (VO2 tot - VO2 stand). To improve measurement of physical activity intensity using accelerometers, research developments are suggested concerning processing of accelerometer data, use of energy expenditure as reference for activity intensity, and calibration procedure with absolute versus relative intensity. This article is protected by copyright. All rights reserved.

  • 6.
    Askling, Carl
    et al.
    Gymnastik- och idrottshögskolan, GIH, Institutionen för idrotts- och hälsovetenskap, Laboratoriet för biomekanik och motorisk kontroll (BMC).
    Karlsson, J
    Thorstensson, Alf
    Gymnastik- och idrottshögskolan, GIH, Institutionen för idrotts- och hälsovetenskap, Laboratoriet för biomekanik och motorisk kontroll (BMC).
    Hamstring injury occurrence in elite soccer players after preseason strength training with eccentric overload.2003Inngår i: Scandinavian Journal of Medicine and Science in Sports, ISSN 0905-7188, E-ISSN 1600-0838, Vol. 13, nr 4, s. 244-50Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The primary purpose of this study was to evaluate whether a preseason strength training programme for the hamstring muscle group - emphasising eccentric overloading - could affect the occurrence and severity of hamstring injuries during the subsequent competition season in elite male soccer players. Thirty players from two of the best premier-league division teams in Sweden were divided into two groups; one group received additional specific hamstring training, whereas the other did not. The extra training was performed 1-2 times a week for 10 weeks by using a special device aiming at specific eccentric overloading of the hamstrings. Isokinetic hamstring strength and maximal running speed were measured in both groups before and after the training period and all hamstring injuries were registered during the total observational period of 10 months. The results showed that the occurrence of hamstring strain injuries was clearly lower in the training group (3/15) than in the control group (10/15). In addition, there were significant increases in strength and speed in the training group. However, there were no obvious coupling between performance parameters and injury occurrence. These results indicate that addition of specific preseason strength training for the hamstrings - including eccentric overloading - would be beneficial for elite soccer players, both from an injury prevention and from performance enhancement point of view.

  • 7.
    Askling, Carl
    et al.
    Gymnastik- och idrottshögskolan, GIH, Institutionen för idrotts- och hälsovetenskap, Laboratoriet för biomekanik och motorisk kontroll (BMC).
    Lund, H
    Saartok, T
    Thorstensson, Alf
    Gymnastik- och idrottshögskolan, GIH, Institutionen för idrotts- och hälsovetenskap, Laboratoriet för biomekanik och motorisk kontroll (BMC).
    Self-reported hamstring injuries in student-dancers.2002Inngår i: Scandinavian Journal of Medicine and Science in Sports, ISSN 0905-7188, E-ISSN 1600-0838, Vol. 12, nr 4, s. 230-5Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Dancing involves powerful movements as well as flexibility exercises, both of which may be related to specific injuries to the musculo-tendinosus tissue, e.g., the hamstring muscle complex. In this study, the occurrence of acute and overuse injuries to the rear thigh in dancers was investigated retrospectively by means of a questionnaire. All but one (n = 98) of the student-dancers (age 17-25 years) at the Ballet Academy in Stockholm participated. The results demonstrated that, during the past 10 years, every third dancer (34%) reported that they had acute injuries and every sixth dancer (17%) had overuse injuries to the rear thigh. Most (91%) of the acute injuries were subjectively located to an area close to tuber ischiadicum. The majority (88%) stated that the acute injury occurred during slow activities in flexibility training, e.g., splits, and only a few (12%) in powerful movements. Continuing problems were reported by 70% of the acutely injured dancers. Many of the dancers neglected their acute injury (14 did not even stop the ongoing dance activity) and they also greatly underestimated the recovery time. Only 4 dancers (12%) received acute medical assistance. Thus the results, based on the recollection of the subjects, indicated that stretching could induce severe strain injuries to the proximal hamstrings in dancers. Extrapolating these results to the practice, it can be recommended that stretching exercises be executed with caution in connection with dancing sessions and training, and that, information about the seriousness and acute treatment of such injuries be added to the student-dancers' curriculum.

  • 8.
    Askling, Carl
    et al.
    Gymnastik- och idrottshögskolan, GIH, Institutionen för idrotts- och hälsovetenskap, Laboratoriet för biomekanik och motorisk kontroll (BMC).
    Tengvar, M
    Saartok, T
    Thorstensson, Alf
    Gymnastik- och idrottshögskolan, GIH, Institutionen för idrotts- och hälsovetenskap, Laboratoriet för biomekanik och motorisk kontroll (BMC).
    Sports related hamstring strains--two cases with different etiologies and injury sites.2000Inngår i: Scandinavian Journal of Medicine and Science in Sports, ISSN 0905-7188, E-ISSN 1600-0838, Vol. 10, nr 5, s. 304-7Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Hamstring strains are common injuries in sports. Knowledge about their etiology and localization is, however, limited. The two cases described here both had acute hamstring strains, but the etiologies were entirely different. The sprinter was injured when running at maximal speed, whereas the hamstring strain in the dancer occurred during slow stretching. Also the anatomical localizations of the injuries clearly differed. Magnetic resonance imaging (MRI) revealed pathological changes in the distal semitendinosus muscle in the sprinter and the proximal tendon of the semimembranosus muscle in the dancer. Subjectively, both athletes severely underestimated the recovery time. These case observations suggest a possible link between etiology and localization of hamstring strains.

  • 9.
    Belz, Johanna
    et al.
    German Sport University Cologne, Cologne, Germany..
    Kenttä, Göran
    Gymnastik- och idrottshögskolan, GIH, Institutionen för fysiologi, nutrition och biomekanik. The School of Human Kinetics, University of Ottawa, Ottawa, Canada.
    McEwan, Hayley E
    School of Health & Life Sciences, University of the West of Scotland, Paisley, England..
    Muetstege, Jelena
    Tod, David
    Lancaster Medical School, Lancaster University, Lancaster, England.
    A qualitative analysis of Swedish sport psychology practitioners' experience of a continued professional development program.2024Inngår i: Scandinavian Journal of Medicine and Science in Sports, ISSN 0905-7188, E-ISSN 1600-0838, Vol. 34, nr 2, artikkel-id e14583Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Although sport psychology practitioners and researchers acknowledge the importance of continued professional development (CPD) for professional effectiveness and excellence, few studies have explored the influence of CPD activities on the practitioners' practice and thinking. This study examined qualified Swedish sport psychology practitioners' experiences of engaging in a CPD program and how it impacted their professional development. The Swedish Sports Confederation offers a CPD program that targets performance enhancement services and psychotherapy for sport psychology practitioners. We explored the influence of this CPD program on the professional development of 13 graduates (five females; age in years: M = 41.2, SD = 8.3) via semi-structured interviews. Our stance involved a realist ontology and constructionist epistemology. We followed the six-step Reflexive Thematic Analysis procedures to analyze data. We identified four themes of CPD: (1) Critique (participants decided to do the CPD program because of perceived gaps in their knowledge and skills), (2) Change (participants discussed several changes as a result of the CPD program), (3) Context (participants discussed the aspects of the CPD program that promoted change), and (4) Challenge (participants mentioned issues related to having completed the program). The study provides insights into the value of CPD activities for sport psychology practitioners, advances current knowledge on practitioner maturation, and illustrates how CPD fits within a practitioner's lifelong learning. Future research could investigate the professional development of mid-career sport psychology practitioners engaging in other CPD programs to confirm or extend this work.

    Fulltekst (pdf)
    fulltext
  • 10.
    Berg, Ulrika
    et al.
    Institutionen för Kvinnors och Barns Hälsa (KBH), Karolinska Institutet.
    Enqvist, Jonas K
    Gymnastik- och idrottshögskolan, GIH, Institutionen för idrotts- och hälsovetenskap, Björn Ekbloms forskningsgrupp.
    Mattsson, C. Mikael
    Gymnastik- och idrottshögskolan, GIH, Institutionen för idrotts- och hälsovetenskap, Björn Ekbloms forskningsgrupp.
    Carlsson-Skwirut, Christine
    Institutionen för Kvinnors och Barns Hälsa (KBH), Karolinska Institutet.
    Sundberg, Carl-Johan
    Institutionen för Fysiologi och Farmakologi, Karolinska institutet.
    Ekblom, Björn
    Gymnastik- och idrottshögskolan, GIH, Institutionen för idrotts- och hälsovetenskap, Björn Ekbloms forskningsgrupp.
    Bang, Peter
    Institutionen för Kvinnors och Barns Hälsa (KBH), Karolinska Institutet.
    Lack of sex differences in the IGF-IGFBP response to ultra endurance exercise.2008Inngår i: Scandinavian Journal of Medicine and Science in Sports, ISSN 0905-7188, E-ISSN 1600-0838, Vol. 18, nr 6, s. 706-714Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The insulin-like growth factor (IGF)-IGF binding proteins (BP) and the pituitary-gonadal axes were investigated during ultra endurance exercise in 16 endurance-trained athletes (seven women). Median duration of the race was 6.3 days. Although food and drink were ad libitum, energy balance was negative. Blood samples were drawn before (PRE), at the end of (END) and 24 h after (POST24h) the race. Serum concentrations of total IGF-I (t-IGF-I) and free IGF-I (f-IGF-I) decreased by 33 (SD 38)% and 54 (19)%, respectively. The decrease in t-IGF-I appeared to be associated to the total energy deficit during the race. At END, the IGFBP-3 fragmentation and IGFBP-1 were increased but these changes did not predict changes in f-IGF-I. An increase in POST24h IGFBP-2 levels in women was the only sex difference. Testosterone was decreased by 67 (12)% in the men and estradiol became undetectable in the women without any detectable increase in LH and/or FSH. In conclusion ultra endurance exercise results in similar IGF-IGFBP responses in men and women reflecting a catabolic state. IGFBP-2 was the only exception, with increased levels in women after exercise. A concomitant decrease in gonadal hormones was not related to endocrine changes in the IGF-IGFBP axis but may be related to local changes in IGF-I expression.

  • 11. Berglund, B
    et al.
    Ekblom, Björn
    Gymnastik- och idrottshögskolan, GIH, Institutionen för idrotts- och hälsovetenskap, Björn Ekbloms forskningsgrupp.
    Ekblom, Elin
    Gymnastik- och idrottshögskolan, GIH, Institutionen för idrotts- och hälsovetenskap, Björn Ekbloms forskningsgrupp.
    Berglund, L
    Kallner, A
    Reinebo, P
    Lindeberg, S
    The Swedish Blood Pass project.2007Inngår i: Scandinavian Journal of Medicine and Science in Sports, ISSN 0905-7188, E-ISSN 1600-0838, Vol. 17, nr 3, s. 292-7Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Manipulation of the blood's oxygen carrying capacity (CaO(2)) through reinfusion of red blood cells, injections of recombinant erythropoietin or by other means results in an increased maximal oxygen uptake and concomitantly enhanced endurance performance. Therefore, there is a need to establish a system--"A Blood Pass"--through which such illegal and unethical methods can be detected. Venous blood samples were taken under standardized conditions from 47 male and female Swedish national and international elite endurance athletes four times during the athletic year of the individual sport (beginning and end of the preparation period and at the beginning and during peak performance in the competition period). In these samples, different hematological values were determined. ON(hes) and OFF(hre) values were calculated according to the formula of Gore et al. A questionnaire regarding training at altitude, alcohol use and other important factors for hematological status was answered by the athletes. There were some individual variations comparing hematological values obtained at different times of the athletic year or at the same time in the athletic year but in different years. However, the median values of all individual hematological, ON(hes) and OFF(hre), values taken at the beginning and the end of the preparation or at the beginning and the end of the competition period, respectively, as well as median values for the preparation and competition periods in the respective sport, were all within the 95% confidence limit (CI) of each comparison. It must be mentioned that there was no gender difference in this respect. This study shows that even if there are some individual variations in different hematological values between different sampling times in the athletic year, median values of important hematological factors are stable over time. It must be emphasized that for each blood sample, the 95% CI in each athlete will be increasingly narrower. The conclusion is that there is a physiological basis for establishing an individual-based "Blood Pass" system, mainly for athletes competing at the international level. On indications of manipulations of hemoglobin concentration and red cell mass by deviations from established "Blood Pass" data, more specific methods can be applied.

  • 12.
    Bjerkefors, Anna
    et al.
    Gymnastik- och idrottshögskolan, GIH, Institutionen för idrotts- och hälsovetenskap, Laboratoriet för biomekanik och motorisk kontroll (BMC).
    Carpenter, M G
    Thorstensson, Alf
    Gymnastik- och idrottshögskolan, GIH, Institutionen för idrotts- och hälsovetenskap, Laboratoriet för biomekanik och motorisk kontroll (BMC).
    Dynamic trunk stability is improved in paraplegics following kayak ergometer training.2007Inngår i: Scandinavian Journal of Medicine and Science in Sports, ISSN 0905-7188, E-ISSN 1600-0838, Vol. 17, nr 6, s. 672-9Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The purpose of the study was to assess whether postural stability in persons with spinal cord injury (SCI) could be affected by training. Ten post-rehabilitated persons with thoracic SCI performed 30 sessions of kayak ergometer training during a 10-week period. The ergometer was modified with a balance module adjustable in the medio-lateral direction. Before and after the training period, horizontal support-surface translations were presented randomly, either in the forward or backward direction, or to the side, while subjects sat in their own wheelchairs. The platform perturbation consisted of an unpredictable initial acceleration, followed by a constant-velocity phase and a predictable deceleration. Markers were applied on the trunk and movement data were recorded in 3D. Four kinematic responses of trunk angular and linear displacement were investigated. In general, postural stability was improved after training with smaller rotational and linear displacements of the trunk observed during both predictable and unpredictable translations in all directions. Thus, the training was able to improve the ability of persons with long-standing SCI to maintain an upright sitting posture in response to externally generated balance perturbations, which should imply an increased capacity to master similar challenges to balance in everyday life.

  • 13. Boushel, Robert
    et al.
    Gnaiger, E
    Larsen, Filip J
    Gymnastik- och idrottshögskolan, GIH, Institutionen för idrotts- och hälsovetenskap.
    Helge, J W
    González-Alonso, J
    Ara, I
    Munch-Andersen, T
    van Hall, G
    Søndergaard, H
    Saltin, Bengt
    Calbet, J A L
    Maintained peak leg and pulmonary VO2 despite substantial reduction in muscle mitochondrial capacity.2015Inngår i: Scandinavian Journal of Medicine and Science in Sports, ISSN 0905-7188, E-ISSN 1600-0838, Vol. 25, nr Suppl 4, s. 135-143Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    We recently reported the circulatory and muscle oxidative capacities of the arm after prolonged low-intensity skiing in the arctic (Boushel et al., 2014). In the present study, leg VO2 was measured by the Fick method during leg cycling while muscle mitochondrial capacity was examined on a biopsy of the vastus lateralis in healthy volunteers (7 male, 2 female) before and after 42 days of skiing at 60% HR max. Peak pulmonary VO2 (3.52 ± 0.18 L.min(-1) pre vs 3.52 ± 0.19 post) and VO2 across the leg (2.8 ± 0.4L.min(-1) pre vs 3.0 ± 0.2 post) were unchanged after the ski journey. Peak leg O2 delivery (3.6 ± 0.2 L.min(-1) pre vs 3.8 ± 0.4 post), O2 extraction (82 ± 1% pre vs 83 ± 1 post), and muscle capillaries per mm(2) (576 ± 17 pre vs 612 ± 28 post) were also unchanged; however, leg muscle mitochondrial OXPHOS capacity was reduced (90 ± 3 pmol.sec(-1) .mg(-1) pre vs 70 ± 2 post, P < 0.05) as was citrate synthase activity (40 ± 3 μmol.min(-1) .g(-1) pre vs 34 ± 3 vs P < 0.05). These findings indicate that peak muscle VO2 can be sustained with a substantial reduction in mitochondrial OXPHOS capacity. This is achieved at a similar O2 delivery and a higher relative ADP-stimulated mitochondrial respiration at a higher mitochondrial p50. These findings support the concept that muscle mitochondrial respiration is submaximal at VO2max , and that mitochondrial volume can be downregulated by chronic energy demand.

  • 14. Calbet, J A L
    et al.
    Mortensen, S P
    Munch, G D W
    Curtelin, D
    Boushel, Robert
    Gymnastik- och idrottshögskolan, GIH, Institutionen för idrotts- och hälsovetenskap, Åstrandlaboratoriet.
    Constant infusion transpulmonary thermodilution for the assessment of cardiac output in exercising humans.2016Inngår i: Scandinavian Journal of Medicine and Science in Sports, ISSN 0905-7188, E-ISSN 1600-0838, Vol. 26, nr 5, s. 518-527Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    To determine the accuracy and precision of constant infusion transpulmonary thermodilution cardiac output (CITT-Q) assessment during exercise in humans, using indocyanine green (ICG) dilution and bolus transpulmonary thermodilution (BTD) as reference methods, cardiac output (Q) was determined at rest and during incremental one- and two-legged pedaling on a cycle ergometer, and combined arm cranking with leg pedaling to exhaustion in 15 healthy men. Continuous infusions of iced saline in the femoral vein (n = 41) or simultaneously in the femoral and axillary (n = 66) veins with determination of temperature in the femoral artery were used for CITT-Q assessment. CITT-Q was linearly related to ICG-Q (r = 0.82, CITT-Q = 0.876 × ICG-Q + 3.638, P < 0.001; limits of agreement ranging from -1.43 to 3.07 L/min) and BTD-Q (r = 0.91, CITT-Q = 0.822 × BTD + 4.481 L/min, P < 0.001; limits of agreement ranging from -1.01 to 2.63 L/min). Compared with ICG-Q and BTD-Q, CITT-Q overestimated cardiac output by 1.6 L/min (≈ 10% of the mean ICG and BTD-Q values, P < 0.05). For Q between 20 and 28 L/min, we estimated an overestimation < 5%. The coefficient of variation of 23 repeated CITT-Q measurements was 6.0% (CI: 6.1-11.1%). In conclusion, cardiac output can be precisely and accurately determined with constant infusion transpulmonary thermodilution in exercising humans.

  • 15.
    Carlsson, Andreas
    et al.
    Gymnastik- och idrottshögskolan, GIH, Institutionen för idrotts- och hälsovetenskap.
    Lundqvist, Carolina
    Gymnastik- och idrottshögskolan, GIH, Institutionen för idrotts- och hälsovetenskap, Forskningsgruppen för idrottspsykologi.
    The Coaching Behavior Scale for Sport (CBS-S): A psychometric evaluation of the Swedish version.2016Inngår i: Scandinavian Journal of Medicine and Science in Sports, ISSN 0905-7188, E-ISSN 1600-0838, Vol. 26, nr 1, s. 116-123Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The present study validated a Swedish version of the 47-item Coaching Behavior Scale for Sport (CBS-S). Sample 1 consisted of 506 team sport athletes [262 men and 244 women; mean age: 22.20, standard deviation (SD) = 3.90] distributed across 41 coaches at the two highest national levels of various sports. Athletes completed the CBS-S and established questionnaires of coaching behaviors (LSS), self-confidence (CSAI-2R), and coach-athlete relationship (CART-Q). An additional sample of 39 basketball players (21 men and 18 women; mean age = 17.40, SD = 2.39) completed the CBS-S twice, approximately 4 weeks apart. Confirmatory factor analysis showed an acceptable model fit for the seven-factor version of the CBS-S, although two items of the negative personal rapport subscale displayed insufficient factor loadings. Correlations between the subscales of the CBS-S and established instruments were in accordance with theoretical expectations, supporting the concurrent validity. Cronbach's alpha (> 0.82) for all dimensions provided support for the reliability of the CBS-S, and test-retest correlations indicated moderate stability over time. Cultural differences in the assessment of coaching behaviors and the usability of the CBS-S by coaches for self-reflection and development are discussed.

  • 16.
    Clement, Damien
    et al.
    College of Physical Activity and Sport Sciences, West Virginia University.
    Ivarsson, Andreas
    Center of Research on Welfare, Health and Sport (CVHI), Halmstad University..
    Tranaeus, Ulrika
    Gymnastik- och idrottshögskolan, GIH, Institutionen för idrotts- och hälsovetenskap. Musculoskeletal and Sports Injury Epidemiology Center, Institute of Environmental Medicine Karolinska Institutet.
    Johnson, Urban
    Center of Research on Welfare, Health and Sport (CVHI), Halmstad University..
    Stenling, Andreas
    Department of Psychology, Umeå University.
    Investigating the influence of intra-individual changes in perceived stress symptoms on injury risk in soccer.2018Inngår i: Scandinavian Journal of Medicine and Science in Sports, ISSN 0905-7188, E-ISSN 1600-0838, Vol. 28, nr 4, s. 1461-1466Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Research has shown that high levels of stress and stress responsivity can increase the risk of injuries. However, most of the research that has supported this notion has focused on between-person relationships, ignoring the relationships at the within-person level. As a result, the objective of this study was to investigate if within-person changes in perceived stress symptoms over a one-month time period could predict injury rates during the subsequent three months. A prospective design with two measurement points (Time 1 - at the beginning of the season and Time 2 - one month into the season) was utilized. A total of 121 competitive soccer players (85 males and 36 females; Mage = 18.39, SD = 3.08) from Sweden and the United States completed the Kessler Psychological Distress Scale (KPDS) and a demographic sheet at Time 1. The KPDS was also completed at Time 2 and all acute injuries that occurred during the subsequent three-month period were recorded. A Bayesian latent change scores model was used to determine if within-person changes in stress symptoms could predict the risk of injury. Results revealed that there was a credible positive effect of changes in stress symptoms on injury rates, indicating that an increase in reported stress symptoms was related to an increased risk for injury. This finding highlights the importance of creating caring and supportive sporting environments and relationships and teaching stress management techniques, especially during the earlier portion of competitive seasons, to possibly reduce the occurrence of injuries. This article is protected by copyright. All rights reserved.

  • 17.
    Clement, Damien
    et al.
    West Virginia University, Morgantown, WV, USA.
    Tranaeus, Ulrika
    Gymnastik- och idrottshögskolan, GIH, Institutionen för fysiologi, nutrition och biomekanik.
    Johnson, Urban
    Halmstad University, Halmstad, Sweden..
    Stenling, Andreas
    Umeå University, Umeå, Sweden..
    Ivarsson, Andreas
    Halmstad University, Halmstad, Sweden; University of Agder, Kristiansand, Norway.
    Profiles of psychosocial factors: Can they be used to predict injury risk?2022Inngår i: Scandinavian Journal of Medicine and Science in Sports, ISSN 0905-7188, E-ISSN 1600-0838, Vol. 32, nr 4, s. 782-788Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The creation of risk profiles using the model of stress and athletic injury (J Appl Sport Psychol. 1998;10(1):5) represents a proposed shift from the reductionism paradigm to the complex sport approach in an attempt to formulate prevention strategies to combat the increasing number of injuries being reported in sporting populations. As a result, the primary purpose of this study was to: (a) identify different risk profiles based on psychosocial factors associated with the Williams and Andersen's model of stress and athletic injury model; and (b) examine potential differences in the frequency of injuries across these risk profiles. A prospective research design was utilized with a sample of 117 competitive soccer players (81 males and 36 females) from Sweden and the United States of America. Data was collected at two time points over the course of three months. At time 1 (beginning of the season) - a demographic information sheet, the Life Event Survey for Collegiate Athletes (LESCA), Sport Competitive Anxiety Test (SCAT), and Brief Cope were administered. At time two (T2), three months after the initial data collection, participants' traumatic injuries were recorded. Latent profile analysis (LPA) showed that 3 profiles solution showed best fit to data. Players in profile 1 and 2 reported fewer injuries compared to players in profile 3. However, whereas individuals in profile 1 had a lower predictive risk of sustaining an injury when compared to those in profile 3, both profiles had similar anxiety levels and use of coping strategies with differing stress levels. These findings suggest that the interaction between different proposed risk factors might influence injury risk.

  • 18.
    Ekblom Bak, Elin
    et al.
    Gymnastik- och idrottshögskolan, GIH, Institutionen för fysisk aktivitet och hälsa.
    Börjesson, Mats
    Center for Health and Performance Department of Molecular and Clinical Medicine Sahlgrenska Academy Gothenburg University Sweden;Dept MGA Sahlgrenska University Hospital Region Västra Götaland Gothenburg Sweden.
    Bergman, Frida
    Department of Public Health and Clinical Medicine Umeå University Umeå Sweden.
    Bergström, Göran
    Department of Molecular and Clinical Medicine Sahlgrenska Academy University of Gothenburg;Clinical Physiology Sahlgrenska University Hospital Gothenburg Sweden.
    Dahlin‐Almevall, Albin
    Department of Health, Learning and Technology Luleå University of Technology Luleå Sweden.
    Drake, Isabel
    Department of Clinical Sciences in Malmö Lund University Malmö Sweden.
    Engström, Gunnar
    Department of Clinical Sciences in Malmö Lund University Malmö Sweden.
    Engvall, Jan E
    CMIV Centre of Medical Image Science and Visualization Linkoping University Linkoping Sweden;Department of Clinical Physiology and Department of Medical and Health Sciences Linköping University Linköping Sweden.
    Gummesson, Anders
    Department of Molecular and Clinical Medicine Sahlgrenska Academy University of Gothenburg;Clinical Genetics and Genomics Sahlgrenska University Hospital Gothenburg Sweden.
    Hagström, Emil
    Department of Medical Sciences Cardiology, Uppsala University Sweden;Uppsala Clinical Research Center Uppsala University Uppsala Sweden.
    Hjelmgren, Ola
    Department of Molecular and Clinical Medicine Sahlgrenska Academy University of Gothenburg;Clinical Physiology Sahlgrenska University Hospital Gothenburg Sweden.
    Jernberg, Tomas
    Department of Clinical Sciences Danderyd University Hospital Karolinska Institutet Stockholm Sweden.
    Johansson, Peter J
    Department of Medical Sciences, Occupational and Environmental Medicine Uppsala University Uppsala University Hospital Uppsala Sweden.
    Lind, Lars
    Department of Medical Sciences Clinical Epidemiology Uppsala University Uppsala Sweden.
    Mannila, Maria
    Heart and Vascular Theme Karolinska University Hospital Stockholm Sweden.
    Nyberg, André
    Department of Community Medicine and Rehabilitation Umeå University Umeå Sweden.
    Persson, Margaretha
    Department of Clinical Sciences in Malmö Lund University Malmö Sweden.
    Reitan, Christian
    Department of Clinical Sciences Danderyd University Hospital Karolinska Institutet Stockholm Sweden.
    Rosengren, Annika
    Department of Molecular and Clinical Medicine Sahlgrenska Academy University of Gothenburg;Clinical Physiology Sahlgrenska University Hospital Gothenburg Sweden.
    Rådholm, Karin
    Department of Health, Medicine and Caring Sciences Linköping University Linköping Sweden.
    Schmidt, Caroline
    Department of Molecular and Clinical Medicine Sahlgrenska Academy University of Gothenburg.
    Sköld, Magnus C
    Department of Respiratory Medicine and Allergy Karolinska University Hospital Solna Stockholm Sweden;Respiratory Medicine Unit Department of Medicine Solna and Center for Molecular Medicine Karolinska Institutet Stockholm Sweden.
    Sonestedt, Emily
    Department of Clinical Sciences in Malmö Lund University Malmö Sweden.
    Sundström, Johan
    Department of Medical Sciences Clinical Epidemiology Uppsala University Uppsala Sweden;The George Institute for Global Health University of New South Wales Sydney Australia.
    Swahn, Eva
    Department of Health, Medicine and Caring Sciences Linköping University Linköping Sweden;Department of Cardiology Linköping University Linköping Sweden.
    Öhlin, Jerry
    Department of Community Medicine and Rehabilitation Umeå University Umeå Sweden.
    Östgren, Carl Johan
    Department of Health, Medicine and Caring Sciences Linköping University Linköping Sweden.
    Ekblom, Örjan
    Gymnastik- och idrottshögskolan, GIH, Institutionen för fysisk aktivitet och hälsa. Department of Physical Activity and Health The Swedish School of Sport and Health Sciences Stockholm Sweden.
    Accelerometer derived physical activity patterns in 27.890 middle‐aged adults – the SCAPIS cohort study2022Inngår i: Scandinavian Journal of Medicine and Science in Sports, ISSN 0905-7188, E-ISSN 1600-0838, Vol. 32, nr 5, s. 866-880Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The present study aims to describe accelerometer-assessed physical activity (PA) patterns and fulfilment of PA recommendations in a large sample of middle-aged men and women, and to study differences between sub-groups of socio-demographic, socio-economic and lifestyle-related variables. A total of 27,890 (92.5% of total participants, 52% women, aged 50-64 years) middle-aged men and women with at least four days of valid hip-worn accelerometer data (Actigraph GT3X+, wGT3X+ and wGT3X-BT) from the Swedish CArdioPulmonary bioImage Study, SCAPIS, were included. In total, 54.5% of daily wear time was spent sedentary, 39.1% in low, 5.4% in moderate, and only 0.1% in vigorous PA. Male sex, higher education, low financial strain, born in Sweden and sedentary/light working situation were related to higher sedentary time, but also higher levels of vigorous PA. High BMI and having multiple chronic diseases associated strongly with higher sedentary time and less time in all three PA intensities. All-year physically active commuters had an overall more active PA pattern. The proportion fulfilling current PA recommendations varied substantially (1.4% to 92.2%) depending on data handling procedures and definition used. Twenty-eight percent was defined as having an "at risk" behaviour, which included both high sedentary time and low vigorous PA. In this large population-based sample, a majority of time was spent sedentary and only a fraction in vigorous PA, with clinically important variations between subgroups. This study provides important reference material and emphasizes the importance of a comprehensive assessment of all aspects of the individual PA pattern in future research and clinical practice.

    Fulltekst (pdf)
    fulltext
  • 19.
    Ekblom Bak, Elin
    et al.
    Gymnastik- och idrottshögskolan, GIH, Institutionen för idrotts- och hälsovetenskap, Åstrandlaboratoriet.
    Ekblom, Örjan
    Gymnastik- och idrottshögskolan, GIH, Institutionen för idrotts- och hälsovetenskap, Åstrandlaboratoriet.
    Andersson, Gunnar
    HPI Health Profile Institute.
    Wallin, Peter
    HPI Health Profile Institute.
    Söderling, Jonas
    Karolinska Institutet.
    Hemmingsson, Erik
    Gymnastik- och idrottshögskolan, GIH, Institutionen för idrotts- och hälsovetenskap. Karolinska Institutet.
    Ekblom, Björn
    Gymnastik- och idrottshögskolan, GIH, Institutionen för idrotts- och hälsovetenskap, Åstrandlaboratoriet, Björn Ekbloms forskningsgrupp.
    Decline in cardiorespiratory fitness in the Swedish working force between 1995 and 2017.2019Inngår i: Scandinavian Journal of Medicine and Science in Sports, ISSN 0905-7188, E-ISSN 1600-0838, Vol. 29, nr 2, s. 232-239Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    BACKGROUND: Long-term trend analyses of cardiorespiratory fitness (VO2 max) in the general population are limited.

    OBJECTIVES: To describe trends in VO2 max from 1995 to 2017 in the Swedish working force and to study developments across categories of sex, age, education, and geographic regions.

    METHODS: 354.277 participants (44% women, 18-74 years) who participated in a nationwide occupational health service screening between 1995 and 2017 were included. Changes in standardized mean values of absolute (L·min-1 ) and relative (ml·min-1 ·kg-1 ) VO2 max, and the proportion with low (<32) relative VO2 max are reported. VO2 max was estimated using a submaximal cycle test.

    RESULTS: Absolute VO2 max decreased by -6.7% (-0.19 L·min-1 ) in the total population. Relative VO2 max decreased by -10.8% (-4.2 ml·min-1 ·kg-1 ) with approximately one-third explained by a simultaneous increase in body mass. Decreases in absolute fitness were more pronounced in men vs. women (8.7% vs. 5.3%), in younger vs. older (6.5% vs 2.3%), in short (11.4%) vs. long (4.5%) education, and in rural vs. urban regions (6.5% vs 3.5%), all p<0.001. The proportions with low VO2 max increased from 27% to 46% (p<0.001).

    CONCLUSION: Between 1995 and 2017, there was a steady and pronounced decline in mean cardiorespiratory fitness in Swedish adults. Male gender, young age, short education and living in a rural area were predictive of greater reductions. The proportion with low cardiorespiratory fitness almost doubled. Given the strong associations between cardiorespiratory fitness and multiple morbidities and mortality, preventing further decreases is a clear public health priority, especially for vulnerable groups. This article is protected by copyright. All rights reserved.

    Fulltekst (pdf)
    fulltext
  • 20.
    Ekblom, Björn
    Gymnastik- och idrottshögskolan, GIH, Institutionen för idrotts- och hälsovetenskap, Åstrandlaboratoriet, Björn Ekbloms forskningsgrupp.
    The muscle biopsy technique: Historical and methodological considerations.2017Inngår i: Scandinavian Journal of Medicine and Science in Sports, ISSN 0905-7188, E-ISSN 1600-0838, Vol. 27, nr 5, s. 458-461Artikkel, forskningsoversikt (Fagfellevurdert)
    Abstract [en]

    The muscle biopsy method is an important tool for clinical and scientific work. In this study, the two most used instruments, the Bergström needle and the Well-Blakesley conchotome, are described. The technique of using those instruments, risks, and other considerations are discussed. Finally, a few consequences and the error of the method for determining muscle fiber type, fiber area, substrates, and metabolites are presented.

  • 21.
    Ekblom, Björn
    et al.
    Gymnastik- och idrottshögskolan, GIH, Institutionen för idrotts- och hälsovetenskap, Åstrandlaboratoriet, Björn Ekbloms forskningsgrupp.
    Ekblom, Örjan
    Gymnastik- och idrottshögskolan, GIH, Institutionen för idrotts- och hälsovetenskap, Åstrandlaboratoriet, Björn Ekbloms forskningsgrupp.
    Stroke volume and the endurance athlete.2006Inngår i: Scandinavian Journal of Medicine and Science in Sports, ISSN 0905-7188, E-ISSN 1600-0838, Vol. 16, nr 1, s. 70-1Artikkel i tidsskrift (Fagfellevurdert)
  • 22.
    Ekblom, Björn
    et al.
    Gymnastik- och idrottshögskolan, GIH, Institutionen för idrotts- och hälsovetenskap, Åstrandlaboratoriet, Björn Ekbloms forskningsgrupp.
    Ekblom, Örjan
    Gymnastik- och idrottshögskolan, GIH, Institutionen för idrotts- och hälsovetenskap, Åstrandlaboratoriet, Björn Ekbloms forskningsgrupp.
    Malm, Christer
    Infectious episodes before and after a marathon race.2006Inngår i: Scandinavian Journal of Medicine and Science in Sports, ISSN 0905-7188, E-ISSN 1600-0838, Vol. 16, nr 4, s. 287-93Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The aim of this study was to investigate the incidence of self-reported infectious episodes (IE) during 3 weeks before (pre-IE) and 3 weeks after (post-IE) a marathon race and relate these figures to training status, running time, socioeconomic and demographic factors. Two questionnaires, including questions about important factors for IE incidence, were given to a representative cohort of 1694 runners (17% of all finishers) in the Stockholm Marathon 2000. Pre-IE incidence in the cohort was 17% with no difference between women and men. Post-IE incidence in the whole cohort was 19% with no significant (P>0.05) difference between women and men. The post-IE incidence in runners without a pre-IE was 16% (P>0.05 to pre-IE incidence). In the group of runners with pre-IE, 33% experienced an IE after the race also (P<0.05 to Pre-IE incidence). A logistic regression analysis showed that younger age and pre race health status and, for men only, experienced nausea during and after the race were depended factors explaining post-IE incidence. Younger runners were more prone to experience IE both before and after the race. There was no relation between training volume 6 months before the race, finishing time and socioeconomic and demographic factors and pre-IE or post-IE. This study does not support the theory of increased infection rate after exhaustive long-distance running ("The Open Window Theory") in recreational runners, but suggests that the sometimes experienced increased rate of infections among athletes can be caused by strenuous exercise too soon after an infection.

  • 23.
    Ekblom, Björn
    et al.
    Gymnastik- och idrottshögskolan, GIH, Institutionen för idrotts- och hälsovetenskap, Åstrandlaboratoriet, Björn Ekbloms forskningsgrupp.
    Engström, Lars-Magnus
    Gymnastik- och idrottshögskolan, GIH, Institutionen för idrotts- och hälsovetenskap, Forskningsgruppen för pedagogik, idrott och fritidskultur.
    Ekblom, Örjan
    Gymnastik- och idrottshögskolan, GIH, Institutionen för idrotts- och hälsovetenskap, Åstrandlaboratoriet, Björn Ekbloms forskningsgrupp.
    Secular trends of physical fitness in Swedish adults.2007Inngår i: Scandinavian Journal of Medicine and Science in Sports, ISSN 0905-7188, E-ISSN 1600-0838, Vol. 17, nr 3, s. 267-73Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The aim of the present study was to study differences in fitness (maximal aerobic power (VO(2max)), balance control, abdominal strength and endurance) and anthropometric data in Swedish women and men (20-65 years of age) between two national cross-sectional samples, studied in 1990/1991 and 2000/2001, respectively. The absolute and relative VO(2max) (aerobic fitness), estimated from a submaximal test, declined with increasing age in both genders. The submaximal test was validated against running VO(2max). Furthermore, the relative aerobic fitness (mL/min/kg) was lower in the 2000/2001 sample in men but not in women. Overall physical activity level was unchanged in both genders. An unexpected finding was that in both samples there were no major differences in relative VO(2max) between men and women of the same age. Combined overweight and obesity (body mass index> or =25) is becoming more prevalent in men, but not in women with prevalence in 2000/2001 of 61% and 38% for men and women, respectively. Balance control and abdominal strength and endurance decrease with increasing age with no differences between the two samples. Thus, the near future health situation for men may be worse, while for women it may be less or no differences compared with today.

  • 24.
    Ekblom-Bak, Elin
    et al.
    Gymnastik- och idrottshögskolan, GIH, Institutionen för idrotts- och hälsovetenskap, Åstrandlaboratoriet, Björn Ekbloms forskningsgrupp.
    Björkman, Frida
    Gymnastik- och idrottshögskolan, GIH, Institutionen för idrotts- och hälsovetenskap, Åstrandlaboratoriet, Björn Ekbloms forskningsgrupp.
    Hellenius, Maj-Lis
    Karolinska Institutet.
    Ekblom, Björn
    Gymnastik- och idrottshögskolan, GIH, Institutionen för idrotts- och hälsovetenskap, Åstrandlaboratoriet, Björn Ekbloms forskningsgrupp.
    A new submaximal cycle ergometer test for prediction of VO(2max).2014Inngår i: Scandinavian Journal of Medicine and Science in Sports, ISSN 0905-7188, E-ISSN 1600-0838, Vol. 24, nr 2, s. 319-326Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Maximal oxygen uptake (VO(2max) ) is an important, independent predictor of cardiovascular health and mortality. Despite this, it is rarely measured in clinical practice. The aim of this study was to create and evaluate a submaximal cycle ergometry test based on change in heart rate (HR) between a lower standard work rate and an individually chosen higher work rate. In a mixed population (n = 143) with regard to sex (55% women), age (21-65 years), and activity status (inactive to highly active), a model included change in HR per unit change in power, sex, and age for the best estimate of VO(2max) . The association between estimated and observed VO(2max) for the mixed sample was r = 0.91, standard error of estimate = 0.302 L/min, and mean measured VO(2max)  = 3.23 L/min. The corresponding coefficient of variation was 9.3%, a significantly improved precision compared with one of the most commonly used submaximal exercise tests, the Åstrand test, which in the present study was estimated to be 18.1%. Test-retest reliability analysis over 1 week revealed no mean difference in the estimated VO(2max) (-0.02 L/min, 95% confidence interval: -0.07-0.03). The new test is low-risk, easily administered, and valid for a wide capacity range, and is therefore suitable in situations as health evaluations in the general population.

  • 25. Eriksson Crommert, Martin
    et al.
    Ekblom, Maria
    Gymnastik- och idrottshögskolan, GIH, Institutionen för idrotts- och hälsovetenskap, Laboratoriet för biomekanik och motorisk kontroll (BMC).
    Thorstensson, Alf
    Gymnastik- och idrottshögskolan, GIH, Institutionen för idrotts- och hälsovetenskap, Laboratoriet för biomekanik och motorisk kontroll (BMC).
    Motor control of the trunk during a modified clean and jerk lift.2014Inngår i: Scandinavian Journal of Medicine and Science in Sports, ISSN 0905-7188, E-ISSN 1600-0838, Vol. 24, nr 5, s. 758-763Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The purpose of the present study was to investigate the pattern of trunk muscle activation and intra-abdominal pressure (IAP) in a somewhat modified version of the clean and jerk lift. Nine healthy physically active male amateurs performed the exercise with a 30-kg barbell. Muscle activity was registered with electromyography from transversus abdominis (TrA) and obliquus internus (OI) using intramuscular electrodes and from rectus abdominis (RA) and erector spinae (ES) with surface electrodes. IAP was recorded with a nasogastric catheter. Measurements were made in various static positions throughout the lift and in the transitional phases separating them, both during lifting and lowering. The results demonstrated that the innermost abdominal muscle, TrA, showed increased activation levels in the two highest positions, whereas ES was most active, together with the highest IAP, in the lowest position. OI and RA showed generally little activation and no obvious trend throughout the lift. The results strengthen the view of a contributing role of TrA to the upright control of the trunk and indicate that the clean and jerk lift might constitute a whole-body exercise, still targeting the TrA muscle, in late-stage rehabilitation, especially for athletes during return to sports.

  • 26.
    Frank, Per
    et al.
    Gymnastik- och idrottshögskolan, GIH, Institutionen för idrotts- och hälsovetenskap, Åstrandlaboratoriet, Forskningsgruppen Mitokondriell funktion och metabolisk kontroll.
    Andersson, Eva
    Gymnastik- och idrottshögskolan, GIH, Institutionen för idrotts- och hälsovetenskap, Åstrandlaboratoriet, Forskningsgruppen Mitokondriell funktion och metabolisk kontroll.
    Pontén, Marjan
    Gymnastik- och idrottshögskolan, GIH, Institutionen för idrotts- och hälsovetenskap, Åstrandlaboratoriet.
    Ekblom, Björn
    Gymnastik- och idrottshögskolan, GIH, Institutionen för idrotts- och hälsovetenskap, Åstrandlaboratoriet, Björn Ekbloms och Mats Börjessons forskningsgrupp.
    Ekblom, Maria
    Gymnastik- och idrottshögskolan, GIH, Institutionen för idrotts- och hälsovetenskap, Laboratoriet för biomekanik och motorisk kontroll (BMC).
    Sahlin, Kent
    Gymnastik- och idrottshögskolan, GIH, Institutionen för idrotts- och hälsovetenskap, Åstrandlaboratoriet, Forskningsgruppen Mitokondriell funktion och metabolisk kontroll.
    Strength training improves muscle aerobic capacity and glucose tolerance in elderly2016Inngår i: Scandinavian Journal of Medicine and Science in Sports, ISSN 0905-7188, E-ISSN 1600-0838, Vol. 26, nr 7, s. 764-773Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The primary aim of this study was to investigate the effect of short-term resistance training (RET) on mitochondrial protein content and glucose tolerance in elderly. Elderly women and men (age 71 ± 1, mean ± SEM) were assigned to a group performing 8 weeks of resistance training (RET, n = 12) or no training (CON, n = 9). The RET group increased in (i) knee extensor strength (concentric +11 ± 3%, eccentric +8 ± 3% and static +12 ± 3%), (ii) initial (0-30 ms) rate of force development (+52 ± 26%) and (iii) contents of proteins related to signaling of muscle protein synthesis (Akt +69 ± 20 and mammalian target of rapamycin +69 ± 32%). Muscle fiber type composition changed to a more oxidative profile in RET with increased amount of type IIa fibers (+26.9 ± 6.8%) and a trend for decreased amount of type IIx fibers (-16.4 ± 18.2%, P = 0.068). Mitochondrial proteins (OXPHOS complex II, IV, and citrate synthase) increased in RET by +30 ± 11%, +99 ± 31% and +29 ± 8%, respectively. RET resulted in improved oral glucose tolerance measured as reduced area under curve for glucose (-21 ± 26%) and reduced plasma glucose 2 h post-glucose intake (-14 ± 5%). In CON parameters were unchanged or impaired. In conclusion, short-term resistance training in elderly not only improves muscular strength, but results in robust increases in several parameters related to muscle aerobic capacity.

  • 27.
    Gilson, Nicholas D
    et al.
    University of Queensland, Brisbane, Australia.
    Andersson, Dan
    Gymnastik- och idrottshögskolan, GIH, Institutionen för fysisk aktivitet och hälsa.
    Papinczak, Zoe E
    University of Queensland, Brisbane, Australia.
    Rutherford, Zoe
    University of Queensland, Brisbane, Australia.
    John, Julie
    University of Queensland, Brisbane, Australia.
    Coombes, Jeff S
    University of Queensland, Brisbane, Australia.
    Brown, Wendy J
    University of Queensland, Brisbane, Australia.
    High intensity and sprint interval training, and work-related cognitive function in adults: A systematic review.2023Inngår i: Scandinavian Journal of Medicine and Science in Sports, ISSN 0905-7188, E-ISSN 1600-0838, Vol. 33, nr 6, s. 814-833Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    OBJECTIVES: To assess evidence on the impact of acute and chronic high intensity interval training (HIIT) and sprint interval training (SIT) on work-related performance tests of cognitive function in adults.

    METHODS: The databases PubMed, CINAHL, Scopus, PsycINFO, Embase and the Cochrane Library were searched for relevant articles up to August 2022. Eligible studies assessed the effects of HIIT (70-100% VO2max ) and/or SIT (≥100% VO2max ) on cognitive function test scores in cognitively healthy adults, relative to a control or comparative exercise group/condition. Data on participant characteristics, exercise protocol, key outcomes and intervention setting were extracted. Study quality was assessed using a 9 (single session HIIT/SIT) and 14 (multiple session HIIT/SIT) item checklist.

    RESULTS: 36 studies (15 countries; n=11 to 945 participants) met inclusion criteria. Mean quality scores were 'fair-to-good' for acute (single session; mean=6.9 [SD 1.0]), and chronic (multiple session; mean=9.8 [SD 1.6]) training studies. Eighteen from 36 studies (12/20 [55%] acute and 6/16 [38%] chronic training studies) evidenced significant improvements in aspects of cognitive function related to work performance (i.e., attention, inhibition, memory, information processing speed, cognitive flexibility, intelligence, reaction time and learning). Only four studies tested the impact of HIIT/SIT on cognitive function in a work-based setting (e.g., the office or home).

    CONCLUSIONS: While there is promising evidence, particularly from acute training studies, to indicate that high intensity, short duration exercise benefits cognitive function in adults, there is very limited evidence of application in workplace contexts. To better understand the potential benefits to employee performance and safety, HIIT/SIT and cognitive function research needs to transition from laboratory to 'in-situ' occupational settings.

    Fulltekst (pdf)
    fulltext
  • 28. Grimby, G
    et al.
    Börjesson, Mats
    Gymnastik- och idrottshögskolan, GIH, Institutionen för idrotts- och hälsovetenskap, Åstrandlaboratoriet, Björn Ekbloms och Mats Börjessons forskningsgrupp.
    Jonsdottir, I H
    Schnohr, P
    Thelle, D S
    Saltin, Bengt
    The "Saltin-Grimby Physical Activity Level Scale" and its application to health research.2015Inngår i: Scandinavian Journal of Medicine and Science in Sports, ISSN 0905-7188, E-ISSN 1600-0838, Vol. 25, nr Suppl 4, s. 119-125Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The use of a four-level questionnaire to assess leisure time physical activity (PA) and its validation is reviewed in this paper. This questionnaire was first published in 1968 and has then been used by more than 600 000 subjects, especially in different population studies in the Nordic countries. A number of modifications to the questionnaire have been published. These are mostly minor changes, such as adding practical examples of activities to illustrate the levels of PA. Some authors have also added duration requirements that were not included for all levels of PA in the original version. The concurrent validity, with respect to aerobic capacity and movement analysis using objective measurements has been shown to be good, as has the predictive validity with respect to various risk factors for health conditions and for morbidity and mortality.

  • 29.
    Holmberg, H-C
    et al.
    Gymnastik- och idrottshögskolan, GIH, Institutionen för idrotts- och hälsovetenskap, Björn Ekbloms forskningsgrupp.
    Rosdahl, Hans
    Gymnastik- och idrottshögskolan, GIH, Institutionen för idrotts- och hälsovetenskap, Laboratoriet för biomekanik och motorisk kontroll (BMC). Gymnastik- och idrottshögskolan, GIH, Institutionen för idrotts- och hälsovetenskap, Laboratoriet för tillämpad idrottsvetenskap (LTIV).
    Svedenhag, J
    Lung function, arterial saturation and oxygen uptake in elite cross country skiers: influence of exercise mode.2007Inngår i: Scandinavian Journal of Medicine and Science in Sports, ISSN 0905-7188, E-ISSN 1600-0838, Vol. 17, nr 4, s. 437-44Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Arterial desaturation during exercise is common in endurance-trained athletes, a phenomenon often more pronounced when the muscle mass engaged in the exercise is large. With this background, the present study monitored seven international-level cross country skiers performing on a treadmill while running (RUN), double poling (DP; upper body exercise) and diagonal skiing (DIA; arm and leg exercise). Static and dynamic lung function tests were performed and oxygen uptake was measured during submaximal and maximal exercise. Lung function variables (including the diffusion capacity) were only 5-20% higher than reported in sedentary men. Vital capacity was considerably lower than expected from the skiers' maximal oxygen uptake (VO(2max)), but the maximal ventilation followed a linear relationship with VO(2max). None or only a mild desaturation was observed in DP, RUN and DIA. Blood lactate concentration was slightly higher in DIA than in DP but not different from RUN. In DIA, VO(2max) was 6.23 +/- 0.47 L/min (mean +/- SD), which was 3.8% and 13.9% higher than in RUN and DP, respectively, with similar peak heart rates for the three exercise modes. No relationships were present either between the degree of desaturation and pulmonary functions tests, or with peak oxygen uptakes. The low blood lactate accumulation during the exhaustive efforts contributed to the arterial oxygen saturation being mild in spite of the very high oxygen uptake observed in these skiers.

  • 30.
    Horwath, Oscar
    et al.
    Gymnastik- och idrottshögskolan, GIH, Institutionen för fysiologi, nutrition och biomekanik.
    Moberg, Marcus
    Gymnastik- och idrottshögskolan, GIH, Institutionen för fysiologi, nutrition och biomekanik.
    Larsen, Filip J
    Gymnastik- och idrottshögskolan, GIH, Institutionen för fysiologi, nutrition och biomekanik.
    Philp, Andrew
    Garvan Institute of Medical Research, Darlinghurst, Sydney, New South Wales, Australia.
    Apro, William
    Gymnastik- och idrottshögskolan, GIH, Institutionen för fysiologi, nutrition och biomekanik. Karolinska institutet, Sweden.
    Ekblom, Björn
    Gymnastik- och idrottshögskolan, GIH, Institutionen för fysiologi, nutrition och biomekanik.
    Influence of sex- and fiber type on the satellite cell pool in human skeletal muscle.2021Inngår i: Scandinavian Journal of Medicine and Science in Sports, ISSN 0905-7188, E-ISSN 1600-0838, Vol. 31, nr 2, s. 303-312Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The repair, remodeling and regeneration of myofibers is dependent on satellite cells (SCs), although, the distribution of SCs in different fiber types of human muscle remains inconclusive. There is also a paucity of research comparing muscle fiber characteristics in a sex-specific manner. Therefore, the aim of this study was to investigate fiber type-specific SC content in men and women. Muscle biopsies from vastus lateralis were collected from 64 young (mean age 27 ± 5), moderately trained men (n=34) and women (n=30). SCs were identified by Pax7-staining together with immunofluorescent analyses of fiber type composition, fiber size and myonuclei content. In a mixed population, comparable number of SCs were associated to type I and type II fibers (0.07 ± 0.02 vs 0.07 ± 0.02 SCs per fiber, respectively). However, unlike men, women displayed a fiber type-specific distribution, with SC content being lower in type II than type I fibers (P=0.041). Sex-based differences were found specifically for type II fibers, where women displayed lower SC content compared to men (P<0.001). In addition, positive correlations (r-values between 0.36-0.56) were found between SC content and type I and type II fiber size in men (P=0.03 and P<0.01, respectively), whereas similar relationships could not be detected in women. Sex-based differences were also noted for fiber type composition and fiber size, but not for myonuclei content. We hereby provide evidence for sex-based differences present at the myocellular level, which may have important implications when studying exercise- and training induced myogenic responses in skeletal muscle.

    Fulltekst (pdf)
    fulltext
  • 31.
    Jonsson Kårström, Malin
    et al.
    Mittuniversitetet, Institutionen för hälsovetenskaper (HOV).
    Stöggl, Thomas
    Lund Ohlsson, Marie
    Mittuniversitetet, Institutionen för hälsovetenskaper (HOV).
    McGawley, Kerry
    Mittuniversitetet, Institutionen för hälsovetenskaper (HOV).
    Laaksonen, Marko S.
    Mittuniversitetet, Institutionen för hälsovetenskaper (HOV).
    Kinematical effects of rifle carriage on roller skiing in well-trained female and male biathletes2023Inngår i: Scandinavian Journal of Medicine and Science in Sports, ISSN 0905-7188, E-ISSN 1600-0838, Vol. 33, nr 4, s. 444-454Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Purpose: This study aimed to investigate how rifle carriage and skiing speed during biathlon roller skiing affect range of motion (ROM) in joint angles and equipment (skis and poles), the vertical distance between shoulders and treadmill (vertdist), as well as possible sex differences associated with rifle carriage. Methods: Fourteen biathletes (6 women, 8 men) roller-skied on a treadmill at submaximal and simulated race speeds, with (WR) and without (NR) a rifle, using gears 3 and 2. Kinematical data for the whole body, poles, roller-skis, rifle, and treadmill were monitored using a 3D motion capture system. Movements determined as flexion/extension (x), abduction/adduction (y), and/or internal/external rotation (z) were analyzed for the hip, shoulder, thorax, knee, ankle, elbow, poles, and roller skis. ROM (the difference between maximal and minimal angles) in joints and equipment, and vertdist were analyzed over six skiing cycles during each condition (WR and NR) and speed. Results: The maximal vertdist was lower for WR compared with NR (gear 3: 1.53 ± 0.06 vs 1.54 ± 0.06 m; gear 2: 1.49 ± 0.06 vs 1.51 ± 0.06 m; both p &lt; 0.001). ROM in the upper body was altered when roller skiing WR (movements decreased in thorax and shoulder (x) and increased in elbow (only gear 3) (x), thorax (only gear 2), and shoulder (y) and (z); all p &lt; 0.05) and increased with speed, without differences between sexes (p &gt; 0.05). Conclusion: Since rifle carriage and speed appear to affect the kinematics of roller skiing, coaches, and biathletes are advised to perform skiing technique training under competition-like conditions (i.e., at race speeds while carrying the rifle). 

  • 32. Jönhagen, S
    et al.
    Halvorsen, Kjartan
    Gymnastik- och idrottshögskolan, GIH, Institutionen för idrotts- och hälsovetenskap, Laboratoriet för biomekanik och motorisk kontroll (BMC).
    Benoit, D L
    Muscle activation and length changes during two lunge exercises: implications for rehabilitation.2009Inngår i: Scandinavian Journal of Medicine and Science in Sports, ISSN 0905-7188, E-ISSN 1600-0838, Vol. 19, nr 4, s. 561-8Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Eccentric exercises are commonly used as a treatment for various muscle and tendon injuries. During complex motions such as the forward lunge, however, it is not always clear which muscles may be contracting eccentrically and at what time. Because this exercise is used during rehabilitation, the purpose of this investigation was to determine what type of contractions take place during two different types of forward lunge and assess the implications for rehabilitation. Five experienced athletes performed five cycles for each of the walking and jumping forward lunges. Motion analysis was used to calculate the shortening or elongation of each muscle based on the change of position of their origin and insertion points during the lunge. Electromyography of the lateral hamstrings, rectus femoris and lateral gastrocnemius was combined with the muscle length change data to determine when isometric, concentric and eccentric activations occur during the lunge. Eccentric contractions in both the quadriceps and gastrocnemius were observed during the lunge. No hamstring eccentric contractions were found; however, the hamstrings showed isometric contractions during the first part of the stance phase.

  • 33.
    Kallings, Lena V
    et al.
    Karolinska institutet.
    Leijon, M
    Hellénius, M-L
    Ståhle, A
    Physical activity on prescription in primary health care: a follow-up of physical activity level and quality of life.2008Inngår i: Scandinavian Journal of Medicine and Science in Sports, ISSN 0905-7188, E-ISSN 1600-0838, Vol. 18, nr 2, s. 154-161Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    To examine whether physical activity on prescription in routine primary care patients would influence physical activity level and quality of life 6 months later. In 2001-2003, 13 Swedish primary health care units took part in an uncontrolled clinical study. If a patient in primary health care needed physical activity preventively or for treatment of a disease and patient-centered motivational counseling found physical activity to be suitable, individualized physical activity could be prescribed. Patients (n=481) of both sexes and all ages [75% women, mean age 50 (12-81)] participated in the study. Self-reported physical activity, readiness to change to a more physically active lifestyle and quality-of-life data were collected through questionnaires. The follow-up rate was 62% at 6 months. Intention-to-treat analysis showed a significant increase (P<0.01) in self-reported physical activity level, the stages of action and maintenance of physical activity as well as quality of life. Physical activity level, stages of change and quality of life increased analogically, indicating that physical activity on prescription may be suitable as a conventional treatment in an ordinary primary health care setting to promote a more physically active lifestyle.

  • 34.
    Kuster, Roman P
    et al.
    Karolinska Institutet, Stockholm, Sweden.
    Grooten, Wilhelmus J A
    Karolinska Institutet, Stockholm, Sweden.
    Baumgartner, Daniel
    ZHAW Zurich University of Applied Sciences, Winterthur, Switzerland..
    Blom, Victoria
    Gymnastik- och idrottshögskolan, GIH, Institutionen för idrotts- och hälsovetenskap, Åstrandlaboratoriet. Karolinska Institutet, Stockholm, Sweden.
    Hagströmer, Maria
    Karolinska Institutet, Stockholm, Sweden.
    Ekblom, Örjan
    Gymnastik- och idrottshögskolan, GIH, Institutionen för idrotts- och hälsovetenskap, Åstrandlaboratoriet.
    Detecting Prolonged Sitting Bouts with the ActiGraph GT3X.2020Inngår i: Scandinavian Journal of Medicine and Science in Sports, ISSN 0905-7188, E-ISSN 1600-0838, Vol. 30, nr 3, s. 572-582Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The ActiGraph has a high ability to measure physical activity, however, it lacks an accurate posture classification to measure sedentary behaviour. The aim of the present study was to develop an ActiGraph (waist-worn, 30Hz) posture classification to detect prolonged sitting bouts, and to compare the classification to proprietary ActiGraph data. The activPAL, a highly valid posture classification device, served as reference criterion.1 Both sensors were worn by 38 office workers over a median duration of 9 days. An automated feature selection extracted the relevant signal information for a minute based posture classification. The machine-learning algorithm with optimal feature number to predict the time in prolonged sitting bouts (≥5 and ≥10 minutes) was searched and compared to the activPAL using Bland-Altman statistics. The comparison included optimised and frequently used cut-points (100 and 150 counts-per-minute (cpm), with and without low-frequency-extension (LFE) filtering). The new algorithm predicted the time in prolonged sitting bouts most accurate (bias ≤7 minutes/day). Of all proprietary ActiGraph methods, only 150 cpm without LFE predicted the time in prolonged sitting bouts non-significantly different from the activPAL (bias ≤18 minutes/day). However, the frequently used 100 cpm with LFE accurately predicted total sitting time (bias ≤7 minutes/day). To study the health effects of ActiGraph measured prolonged sitting, we recommend using the new algorithm. In case a cut-point is used, we recommend 150 cpm without LFE to measure prolonged sitting, and 100 cpm with LFE to measure total sitting time. However, both cpm cut-points are not recommended for a detailed bout analysis.

  • 35.
    Lundkvist, Erik
    et al.
    Gymnastik- och idrottshögskolan, GIH, Institutionen för idrotts- och hälsovetenskap. Stockholm University; University of St Andrews, UK.
    Gustafsson, H
    Karlstad university.
    Davis, P A
    Umeå university.
    Holmström, S
    Umeå university.
    Lemyre, N
    Norwegian School of Sport Sciences, Oslo, Norway.
    Ivarsson, A
    Halmstad university.
    The temporal relations across burnout dimensions in athletes.2018Inngår i: Scandinavian Journal of Medicine and Science in Sports, ISSN 0905-7188, E-ISSN 1600-0838, Vol. 28, nr 3, s. 1215-1226Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Burnout is a construct that has garnered considerable attention in sport psychology within recent years. Several hypothesized models regarding how the three dimensions (exhaustion, devaluation, and reduced sense of accomplishment) temporally relate to each other have been advanced. One proposal outlined by Maslach and Leiter suggests that exhaustion predicts devaluation which predicts reduced sense of accomplishment. However, there is no consensus among researchers as it has been argued that exhaustion predicts devaluation and reduced accomplishment separately. The aim of this study was to test multiple alternative hypotheses regarding the relationships of the burnout dimensions in athletes. Two samples of Swedish youth elite athletes with differing time spans between measurements were used. Specifically, one sample involved time-intensive measures collected every week over an eight-week period, and the other sample included four measurement points across an 18-month period. Results showed that none of the previously proposed models outlining the temporal relations of burnout dimensions were supported. Statistical analysis of the models including the cross-lagged predictions of dimensions did not have any statistically significant impact except when exhaustion negatively predicted devaluation between time 1 (month 0) and time 2 (month 6) in the 18-month sample; this relation faded in the following time points. Further, issues regarding the stability of devaluation and reduced sense of accomplishment emerged as their autocorrelation were very weak in the time-intensive sample. These findings raise a number of points for further theoretical and practical discussions about the athlete burnout construct.

  • 36.
    Lundqvist, Carolina
    et al.
    Gymnastik- och idrottshögskolan, GIH, Institutionen för idrotts- och hälsovetenskap, Forskningsgruppen för idrottspsykologi.
    Kenttä, Göran
    Gymnastik- och idrottshögskolan, GIH, Institutionen för idrotts- och hälsovetenskap, Forskningsgruppen för idrottspsykologi.
    Raglin, John. S
    Indiana University-Bloomington.
    Directional anxiety responses in elite and sub-elite young athletes:: Intensity of anxiety symptoms matter2011Inngår i: Scandinavian Journal of Medicine and Science in Sports, ISSN 0905-7188, E-ISSN 1600-0838, Vol. 21, nr 6, s. 853-862Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The objective was to examine the differences in anxiety ratings of elite and sub-elite athletes when the relationship between intensity and direction scores of anxiety ratings is considered in analyses. Participants were 31 junior elite (Mean age: 17.7, SD = 1.1) and 53 sub-elite (Mean age: 17.5 years, SD = 1.1) cross-country skiers and swimmers who completed the direction modified CSAI-2R before important competitions. Results showed that elite athletes  rated a higher percent of items as facilitative to their performance whereas sub-elite athletes rated a higher percent of items as debilitative. No significant differences between the elite and sub-elite samples were displayed regarding rated direction scores of cognitive or somatic anxiety at moderate to high intensity levels. A significant difference in facilitative anxiety ratings was displayed at a low anxiety intensity level (Z = -2.20, p < .05). Outcome performance data showed no consistent congruence with athletes’ anxiety direction ratings. The findings suggest that facilitative direction scores are a consequence of low anxiety intensity, possibly combined with high self-confidence levels. Directional anxiety researchers analysing separate total scores of intensity and direction respectively, which is the traditional approach, may draw incorrect conclusions about the importance of facilitative ratings of anxiety symptoms.  

  • 37.
    Mattsson, C. Mikael
    et al.
    Gymnastik- och idrottshögskolan, GIH, Institutionen för idrotts- och hälsovetenskap, Björn Ekbloms forskningsgrupp.
    Enqvist, Jonas K
    Gymnastik- och idrottshögskolan, GIH, Institutionen för idrotts- och hälsovetenskap, Björn Ekbloms forskningsgrupp.
    Brink-Elfegoun, Thibault
    Gymnastik- och idrottshögskolan, GIH, Institutionen för idrotts- och hälsovetenskap, Björn Ekbloms forskningsgrupp.
    Johansson, Patrik H
    Gymnastik- och idrottshögskolan, GIH, Institutionen för idrotts- och hälsovetenskap, Björn Ekbloms forskningsgrupp.
    Bakkman, Linda
    Gymnastik- och idrottshögskolan, GIH.
    Ekblom, Björn
    Gymnastik- och idrottshögskolan, GIH, Institutionen för idrotts- och hälsovetenskap, Björn Ekbloms forskningsgrupp.
    Reversed drift in heart rate but increased oxygen uptake at fixed work rate during 24 h ultra-endurance exercise.2010Inngår i: Scandinavian Journal of Medicine and Science in Sports, ISSN 0905-7188, E-ISSN 1600-0838, Vol. 20, nr 2, s. 298-304Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In this paper we report a reversed drift in heart rate (HR) but increased oxygen uptake (VO(2)) during ultra-endurance exercise. Nine well-trained male athletes performed 24-h exercise in a controlled laboratory setting, with alternating blocks of kayaking, running and cycling. Each block included 110 min of exercise and 10 min of rest, with an average work intensity of approximately 55% of respective VO(2peak). Blood samples were taken and HR and VO(2) measured every 6th hour during steady-state cycling at fixed work rate. As assumed HR was increased at 6 h by 15 +/- 6 beats/min compared with initial level (0 h). Thereafter the drift did not progress continuously, but instead unexpectedly returned toward initial values, although the plasma levels of catecholamines increased continuously during exercise. VO(2) was increased by 0.22 +/- 0.15 L/min (10%) at 6 h and 0.37 +/- 0.18 L/min (17%) at 12 h compared with 0 h, and thereafter remained stable. This implies an increased oxygen pulse (VO(2)/HR) by approximately 10% at the last half of the 24-h exercise compared with 0 h. Consequently, sole use of HR would give inaccurate estimates of exercise intensity and energy expenditure during endurance exercise lasting more than 6 h, and different patterns of cardiovascular drift need to be taken into account.

  • 38.
    Nordlund Ekblom, Maria
    et al.
    Gymnastik- och idrottshögskolan, GIH, Institutionen för idrotts- och hälsovetenskap, Laboratoriet för biomekanik och motorisk kontroll (BMC).
    Thorstensson, Alf
    Gymnastik- och idrottshögskolan, GIH, Institutionen för idrotts- och hälsovetenskap, Laboratoriet för biomekanik och motorisk kontroll (BMC).
    Strength training effects of whole-body vibration?2007Inngår i: Scandinavian Journal of Medicine and Science in Sports, ISSN 0905-7188, E-ISSN 1600-0838, Vol. 17, nr 1, s. 12-7Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Whole-body vibration (WBV) has been suggested to have a beneficial effect on muscle strength. Manufacturers of vibration platforms promote WBV as an effective alternative or complement to resistance training. This study aimed to review systematically the current (August 2005) scientific support for effects of WBV on muscle strength and jump performance. MEDLINE and SPORT DISCUS were searched for the word vibration in combination with strength or training. Twelve articles were included in the final analysis. In four of the five studies that used an adequate design with a control group performing the same exercises as the WBV group, no difference in performance improvement was found between groups, suggesting no or only minor additional effects of WBV as such. Proposed neural mechanisms are discussed.

  • 39. Nordsborg, N B
    et al.
    Robach, P
    Boushel, Robert
    Gymnastik- och idrottshögskolan, GIH, Institutionen för idrotts- och hälsovetenskap, Åstrandlaboratoriet.
    Calbet, J A L
    Lundby, C
    Erythropoietin does not reduce plasma lactate, H(+) , and K(+) during intense exercise.2015Inngår i: Scandinavian Journal of Medicine and Science in Sports, ISSN 0905-7188, E-ISSN 1600-0838, Vol. 25, nr 6, s. e566-e575Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    It is investigated if recombinant human erythropoietin (rHuEPO) treatment for 15 weeks (n = 8) reduces extracellular accumulation of metabolic stress markers such as lactate, H(+) , and K(+) during incremental exhaustive exercise. After rHuEPO treatment, normalization of blood volume and composition by hemodilution preceded an additional incremental test. Group averages were calculated for an exercise intensity ∼80% of pre-rHuEPO peak power output. After rHuEPO treatment, leg lactate release to the plasma compartment was similar to before (4.3 ± 1.6 vs 3.9 ± 2.5 mmol/min) and remained similar after hemodilution. Venous lactate concentration was higher (P < 0.05) after rHuEPO treatment (7.1 ± 1.6 vs 5.2 ± 2.1 mM). Leg H(+) release to the plasma compartment after rHuEPO was similar to before (19.6 ± 5.4 vs 17.6 ± 6.0 mmol/min) and remained similar after hemodilution. Nevertheless, venous pH was lower (P < 0.05) after rHuEPO treatment (7.18 ± 0.04 vs 7.22 ± 0.05). Leg K(+) release to the plasma compartment after rHuEPO treatment was similar to before (0.8 ± 0.5 vs 0.7 ± 0.7 mmol/min) and remained similar after hemodilution. Additionally, venous K(+) concentrations were similar after vs before rHuEPO (5.3 ± 0.3 vs 5.1 ± 0.4 mM). In conclusion, rHuEPO does not reduce plasma accumulation of lactate, H(+) , and K(+) at work rates corresponding to ∼80% of peak power output.

  • 40.
    Nyberg, Gisela
    et al.
    Karolinska Institutet, Stockholm, Sweden.
    Ekelund, U
    Marcus, C
    Physical activity in children measured by accelerometry: stability over time.2009Inngår i: Scandinavian Journal of Medicine and Science in Sports, ISSN 0905-7188, E-ISSN 1600-0838, Vol. 19, nr 1, s. 30-5Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The aim of this study was to examine the stability of objectively measured physical activity in Swedish children and to study variables that predicted physical activity and body mass index standard deviation score (BMI SDS) at follow-up. A total of 97 children provided valid repeated measurements of physical activity between 2002 and 2005. The children were on average 7.5 years at baseline (SD+/-0.92) and 9 years at follow-up (SD+/-0.92). The mean follow-up time was approximately 1.5 years (mean 558 days, SD+/-224). An accelerometer (Actiwatch, Cambridge Neurotechnology Ltd., Cambridge, UK) was used to measure physical activity during 7 consecutive days. Yearly weight and height were examined and BMI SDS was calculated. Baseline physical activity was significantly correlated with physical activity at follow-up (r=0.59) with a stronger correlation for boys (r=0.72) than for girls (r=0.51). High physical activity levels were more stable (r=0.74) than low physical activity levels (r=0.55). Physical activity at follow-up was explained by physical activity at baseline and season (R(2)=0.46) whereas BMI SDS at follow-up was explained by BMI SDS at baseline and age (R(2)=0.90). The results of this study suggest that physical activity levels are fairly stable in 6-10-year-old children.

  • 41.
    Olsson, Sven Johan Gustav
    et al.
    Gymnastik- och idrottshögskolan, GIH, Institutionen för idrotts- och hälsovetenskap, Åstrandlaboratoriet, Björn Ekbloms forskningsgrupp.
    Ekblom-Bak, Elin
    Gymnastik- och idrottshögskolan, GIH, Institutionen för idrotts- och hälsovetenskap, Åstrandlaboratoriet, Björn Ekbloms forskningsgrupp.
    Ekblom, Björn
    Gymnastik- och idrottshögskolan, GIH, Institutionen för idrotts- och hälsovetenskap, Åstrandlaboratoriet, Björn Ekbloms forskningsgrupp.
    Kallings, Lena V
    Gymnastik- och idrottshögskolan, GIH, Institutionen för idrotts- och hälsovetenskap, Åstrandlaboratoriet, Björn Ekbloms forskningsgrupp.
    Ekblom, Örjan
    Gymnastik- och idrottshögskolan, GIH, Institutionen för idrotts- och hälsovetenskap, Åstrandlaboratoriet, Björn Ekbloms forskningsgrupp.
    Börjesson, Mats
    Gymnastik- och idrottshögskolan, GIH, Institutionen för idrotts- och hälsovetenskap, Åstrandlaboratoriet. Göteborg University.
    Association of perceived physical health and physical fitness in two Swedish national samples from 1990 and 2015.2018Inngår i: Scandinavian Journal of Medicine and Science in Sports, ISSN 0905-7188, E-ISSN 1600-0838, Vol. 28, nr 2, s. 717-724Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    BACKGROUND: Perceived health and physical fitness have been shown to correlate, and low levels of either variable increase the risk for future illness and mortality. However, risk factors and their interrelationship may vary between societies and over time. In this study, the associations of physical fitness and perceived health were therefore assessed in two Swedish national samples 25 years apart.

    METHODS: Perceived physical health, dichotomized as "good" or "bad", maximal oxygen uptake (VO2 max), counter movement jump (CMJ), balance (one-legged 60 second stance), and self-reported demographics and lifestyle were recorded in two cross-sectional samples (sample size, number of eligible participants) of Swedish adults, aged 20 - 65 years, in 1990 - 1991 (2203, 1365), and 2013 - 2015 (3357, 422).

    RESULTS: The odds for good perceived physical health increased by 5% per mL · kg(-1) · min(-1) of VO2 max, 3% per cm CMJ height, and decreased by 4% per 1 time of overbalancing, in both samples. Mutually adjusted regression models showed that perceived physical health was best predicted by VO2 max and chronic illness in 1990 and by age, BMI, and educational level in 2015.

    CONCLUSION: Perceived physical health was related to physical fitness in two samples of Swedish adults from 1990 and 2015. However, multivariate, and mutually adjusted models, indicate that the most important covariates of perceived physical health may have changed from VO2 max and chronic illness in 1990, to age, BMI, and educational level in 2015. This article is protected by copyright. All rights reserved.

  • 42.
    Pineda, Roi Charles
    et al.
    Department of Rehabilitation Sciences, Faculty of Movement and Rehabilitation Sciences, Leuven, Belgium.
    Krampe, Ralf Th
    Brain & Cognition Group, Faculty of Psychology and Educational Sciences, Leuven, Belgium..
    Vanlandewijck, Yves
    Gymnastik- och idrottshögskolan, GIH, Institutionen för fysisk aktivitet och hälsa. Department of Rehabilitation Sciences, Faculty of Movement and Rehabilitation Sciences, Leuven, Belgium.
    Van Biesen, Debbie
    Department of Rehabilitation Sciences, Faculty of Movement and Rehabilitation Sciences, Leuven, Belgium.
    Cognitive-motor multitasking in athletes with and without intellectual impairment.2022Inngår i: Scandinavian Journal of Medicine and Science in Sports, ISSN 0905-7188, E-ISSN 1600-0838, Vol. 32, nr 2, s. 424-434Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    PURPOSE: We investigated cognitive-motor multitasking in 29 top athletes with intellectual impairment (II) recruited during the European Championship Games organized by Virtus (World Intellectual Impairment Sports) and 29 control (CT) athletes matched for age, sex, sports practiced, and lifetime accumulated practice hours.

    METHODS: Participants performed a cognitive task that required recognizing previously displayed visual objects among distractors. The motor task required maintaining a stable upright posture balancing on a rocking board placed atop a force plate which assessed center-of-pressure (COP) movement. Both tasks were performed separately (with participants seated for the cognitive single task) and concurrently under dual-task conditions, wherein participants memorized objects while balancing. We analyzed recognition accuracy, COP path length, and sample entropy of the COP trajectory as a measure for automaticity of postural control.

    RESULTS: As expected, CT-athletes outperformed II-athletes in the cognitive task but the two groups have comparable performance in the postural task under single- and dual-task conditions. When multitasking, CT-athletes switched to more automatic postural control and maintained their postural sway at single-task levels. II-athletes prioritized balance thereby successfully keeping COP excursion comparable to single-task conditions. However, this came with pronounced costs for memory performance, which was unaffected by multitasking in CT-athletes.

    CONCLUSION: The adaptive capacity observed in control athletes was not at the disposal of II-athletes who revealed pronounced sensitivities to multitasking interference. This sensitivity obviously was not compensated for by either athletic competence or potential transfer of athletic skill to domain-general cognitive functions.

  • 43.
    Psilander, Niklas
    et al.
    Gymnastik- och idrottshögskolan, GIH, Institutionen för idrotts- och hälsovetenskap, Åstrandlaboratoriet, Forskningsgruppen Mitokondriell funktion och metabol kontroll.
    Frank, Per
    Gymnastik- och idrottshögskolan, GIH, Institutionen för idrotts- och hälsovetenskap, Åstrandlaboratoriet, Forskningsgruppen Mitokondriell funktion och metabol kontroll.
    Flockhart, Mikael
    Gymnastik- och idrottshögskolan, GIH, Institutionen för idrotts- och hälsovetenskap, Åstrandlaboratoriet, Forskningsgruppen Mitokondriell funktion och metabol kontroll.
    Sahlin, Kent
    Gymnastik- och idrottshögskolan, GIH, Institutionen för idrotts- och hälsovetenskap, Åstrandlaboratoriet, Forskningsgruppen Mitokondriell funktion och metabol kontroll.
    Adding strength to endurance training does not enhance aerobic capacity in cyclists2015Inngår i: Scandinavian Journal of Medicine and Science in Sports, ISSN 0905-7188, E-ISSN 1600-0838, Vol. 25, nr 4, s. e353-e359Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The molecular signaling of mitochondrial biogenesis is enhanced when resistance exercise is added to a bout of endurance exercise. The purpose of the present study was to examine if this mode of concurrent training translates into increased mitochondrial content and improved endurance performance. Moderately trained cyclists performed 8 weeks (two sessions per week) of endurance training only (E, n = 10; 60-min cycling) or endurance training followed by strength training (ES, n = 9; 60-min cycling + leg press). Muscle biopsies were obtained before and after the training period and analyzed for enzyme activities and protein content. Only the ES group increased in leg strength (+19%, P < 0.01), sprint peak power (+5%, P < 0.05), and short-term endurance (+9%, P < 0.01). In contrast, only the E group increased in muscle citrate synthase activity (+11%, P = 0.06), lactate threshold intensity (+3%, P < 0.05), and long-term endurance performance (+4%, P < 0.05). Content of mitochondrial proteins and cycling economy was not affected by training. Contrary to our hypothesis, the results demonstrate that concurrent training does not enhance muscle aerobic capacity and endurance performance in cyclists.

  • 44.
    Póvoas, Susana
    et al.
    University Institute of Maia, ISMAI, Maia, Portugal..
    Ascensão, António
    University of Porto, Porto, Portugal..
    Magalhães, Josė
    University of Porto, Porto, Portugal..
    Silva, Pedro
    University Institute of Maia, ISMAI, Maia, Portugal..
    Wiig, Håvard
    Norwegian School of Sport Sciences, Oslo, Norway.
    Raastad, Truls
    Norwegian School of Sport Sciences, Oslo, Norway.
    Castagna, Carlo
    Italian Football Federation (FIGC), (Florence), Italy..
    Andersson, Helena A
    Gymnastik- och idrottshögskolan, GIH, Institutionen för fysiologi, nutrition och biomekanik.
    Technical match actions and plasma stress markers in elite female football players during an official FIFA Tournament.2022Inngår i: Scandinavian Journal of Medicine and Science in Sports, ISSN 0905-7188, E-ISSN 1600-0838, Vol. 32, nr Suppl 1, s. 127-139Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    This study analyzed the impact of performing four consecutive football matches separated by 48-72 hours during a FIFA tournament on physical load, technical performance and plasma markers of redox state, muscle damage and inflammation in elite female players. Forty-eight players from three national teams were evaluated at seven time points: before (baseline) and throughout the tournament (after each match and before two training sessions). Only data from players who played all matches were included in the analyses (N = 13). The players were divided into high-rank (N = 6) and low-rank (N = 7) team players according to FIFA standards. Plasma creatine kinase (CK), C-reactive protein (CRP), total antioxidant status (TAS), and uric acid (UA) were analyzed at the selected time points. Technical performance and physical load were also quantified according to team rank. Players from low-rank teams played significantly more time than high-rank players (85 ± 10 vs 67 ± 15 minutes; P = .02; d = 1.51). Low-rank team players presented higher values in technical performance actions than the high-rank team players, but most of the differences were explained by the longer match time played. UA content differed across the matches, increasing from baseline (F(4,40)  = 3.90; P = .01) and more in the high-rank team players (F(1,10)  = 20.46; P = .001), while CRP only differed across the matches (F(4,36)  = 2.66; P = .05), also increasing from baseline. A large time effect was shown for UA only in the high-rank players (η2p  = 0.50; P = .02). Four consecutive matches did not result in considerable alterations in plasma stress markers, physical load, and technical performance in elite female football players from distinct rank levels.

  • 45. Rud, Bjarne
    et al.
    Secher, N H
    Nilsson, Johnny
    Gymnastik- och idrottshögskolan, GIH, Institutionen för idrotts- och hälsovetenskap, Laboratoriet för tillämpad idrottsvetenskap (LTIV).
    Smith, G
    Hallén, J
    Metabolic and mechanical involvement of arms and legs in simulated doule pole skiing2014Inngår i: Scandinavian Journal of Medicine and Science in Sports, ISSN 0905-7188, E-ISSN 1600-0838, Vol. 24, nr 6, s. 913-919Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    We evaluated arm and leg work rate and metabolism during double pole ergometer skiing. Thermodilution arm and leg blood flow was determined together with the arterial to venous difference for oxygen, while the work rate was assessed in eight male recreational skiers [24 (SD 7) years]. When work rate increased from 82 (SE 4) to 117 (7) W, leg power increased by 43% (enhanced vertical force and displacement of the body). The elbow angle tended to increase [from 71 (11.3)° to 75 (10.9)°; P = 0.07] and arm oxygen uptake increased by 20 (5)% [from 0.65 (0.07) to 0.78 (0.08) L/min; P < 0.05] because two-arm blood flow increased [from 5.4 (0.6) to 6.3 (0.7) L/min; P < 0.05] with no significant change in oxygen extraction [from 59 (2.3)% to 60 (1.9)%] accompanied with net arm lactate and potassium release. In contrast, two-leg blood flow [from 5.8 (0.5) to 8.0 (0.5) L/min] and oxygen extraction [from 67 (1.3)% to 75 (1.5)%] increased (P < 0.05), resulting in a 53 (8)% increase in leg oxygen uptake [from 0.82 (0.06) to 1.24 (0.07) L/min; P < 0.05]. In conclusion, during double poling on an ergometer, arm muscle metabolism and work rate increase only marginally and an increase in work intensity is covered mainly by the leg muscles.

  • 46. Saldanha, A
    et al.
    Nordlund Ekblom, Maria M
    Gymnastik- och idrottshögskolan, GIH, Institutionen för idrotts- och hälsovetenskap, Laboratoriet för biomekanik och motorisk kontroll (BMC).
    Thorstensson, Alf
    Gymnastik- och idrottshögskolan, GIH, Institutionen för idrotts- och hälsovetenskap, Laboratoriet för biomekanik och motorisk kontroll (BMC).
    Central fatigue affects plantar flexor strength after prolonged running.2008Inngår i: Scandinavian Journal of Medicine and Science in Sports, ISSN 0905-7188, E-ISSN 1600-0838, Vol. 18, nr 3, s. 383-8Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The primary aim of this study was to examine central fatigue of the plantar flexor muscle group after prolonged running using the twitch interpolation technique. Eight healthy, habitually active male subjects ran on a motorized treadmill for 2 h at a speed corresponding to 75% of peak oxygen uptake (VO(2peak)). Maximal voluntary isometric contraction (MVC) strength as well as the electrically induced twitch produced during MVC [interpolated twitch (IT)] and at rest [resting twitch (RT)] were measured before and after running. The level of activation (LOA) during each MVC was calculated as LOA (%)=100(1-IT/RT). Both MVC and LOA decreased (17+/-16% and 19+/-15%, respectively, P<0.05) after running, whereas RT did not change. The decrease in MVC was correlated with the decrease in LOA (r=0.87, P<0.05). The results demonstrate that after 2 h of treadmill running at an intensity of 75% of VO(2peak), there was a reduction in maximal voluntary plantar flexor muscle strength that was mainly related to central fatigue.

  • 47.
    Salier Eriksson, Jane
    et al.
    Gymnastik- och idrottshögskolan, GIH, Institutionen för idrotts- och hälsovetenskap, Åstrandlaboratoriet, FoU-gruppen för rörelse, hälsa och miljö.
    Ekblom, Björn
    Gymnastik- och idrottshögskolan, GIH, Institutionen för idrotts- och hälsovetenskap, Åstrandlaboratoriet, Björn Ekbloms forskningsgrupp.
    Kallings, Lena
    Gymnastik- och idrottshögskolan, GIH, Institutionen för idrotts- och hälsovetenskap, Åstrandlaboratoriet.
    Hemmingsson, Erik
    Gymnastik- och idrottshögskolan, GIH, Institutionen för idrotts- och hälsovetenskap, Åstrandlaboratoriet.
    Andersson, Gunnar
    HPI Health Profile Institute.
    Wallin, Peter
    HPI Health Profile Institute.
    Ekblom, Örjan
    Gymnastik- och idrottshögskolan, GIH, Institutionen för idrotts- och hälsovetenskap, Åstrandlaboratoriet.
    Ekblom Bak, Elin
    Gymnastik- och idrottshögskolan, GIH, Institutionen för idrotts- och hälsovetenskap, Åstrandlaboratoriet.
    Active commuting in Swedish workers between 1998 and 2015 - trends, characteristics and cardiovascular disease risk.2020Inngår i: Scandinavian Journal of Medicine and Science in Sports, ISSN 0905-7188, E-ISSN 1600-0838, Vol. 30, nr 2Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    BACKGROUND: Trend analyses of active commuting and potential variations in trends and association with cardiovascular disease (CVD) risk within sub-groups are unknown.

    OBJECTIVES: To a) describe trends in active commuting between 1998 to 2015 and b) to study the association between different amounts of active commuting and the incidence risk of CVD in a large sample of Swedish workers, and analyses of potential variations across sub-groups of socio-demographics, physical activity and BMI.

    METHODS: A total of 318,309 participants (47% women, 18-74 years) who participated in a nationwide occupational health service screening between 1998 and 2015 were included. Commuting habits were self-reported, and data on first-time CVD events were derived from national registers.

    RESULTS: Self-reported passive commuters decreased between 1998 and 2015 (64% to 56%), transferring to an increase in mainly moderate/high-dose active commuters (12% to 19%). Changes were seen in all subgroups. The characteristics and life-style habits of the typical passive and active commuter changed little over the study period. Low- and moderate/high-dose active commuters had significantly decreased risks for a first time CVD during follow-up. This was accentuated in men, middle-aged and in participants with light physical work situations, irregular exercise habits, being overweight/obese and with low fitness.

    CONCLUSION: Increases in active commuting were observed between 1998 and 2015, however still leaving a majority who do not actively commute. As active commuting, regardless dose, is associated with a lower CVD risk, encouraging more people to actively commute may provide an easily accessible and time-efficient possibility to increase physical activity and health in the general population.

    Fulltekst (pdf)
    fulltext
  • 48.
    Schantz, Peter
    Gymnastik- och idrottshögskolan, GIH, Institutionen för idrotts- och hälsovetenskap, Åstrandlaboratoriet, FoU-gruppen för rörelse, hälsa och miljö.
    Along paths converging to Bengt Saltin´s early contributions in exercise physiology2015Inngår i: Scandinavian Journal of Medicine and Science in Sports, ISSN 0905-7188, E-ISSN 1600-0838, Vol. 25, nr Suppl. 4, s. 7-15Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A fascinating chain of events led in 1941 to the formation of the Department of Physiology at the Royal Gymnastic Central Institute (GCI) in Stockholm, Sweden. Erik Hohwü Christensen, from the scientifically advanced Lindhard School in Copenhagen, became its first professor. A central research question for him concerned determining the limiting factors for maximal physical performance in man. This was the academic setting where the sports interested medical student Bengt Saltin was introduced to exercise physiology. In the summer of 1959 he became involved in a study on intermittent versus continuous running. A doctoral project, with Per-Olof Åstrand as his tutor, resulted in 1964 as the thesis ‘Aerobic work capacity and circulation at exercise in man. With special reference to the effect of prolonged exercise and/or heat exposure’. In the decade that followed, Saltin continued along that path. However, he also added a vital research line involving pioneering studies on skeletal muscles in the exercising man, a series of novel studies on the physiological demands in various sports, and studies of the effects of physical training within the general population.

    Fulltekst (pdf)
    fulltext
  • 49. Sundblad, Gunilla
    et al.
    Saartok, Tönu
    Engström, Lars-Magnus
    Gymnastik- och idrottshögskolan, GIH, Institutionen för idrotts- och hälsovetenskap, Forskningsgruppen för pedagogik, idrott och fritidskultur.
    Renström, Per
    Injuries during physical activity in school children.2005Inngår i: Scandinavian Journal of Medicine and Science in Sports, ISSN 0905-7188, E-ISSN 1600-0838, Vol. 15, nr 5, s. 313-23Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    During the spring of 2001, 1975 children, from grades 3, 6 and 9 participated in a nationwide, multidisciplinary collaboration study. The students came from randomly selected classes throughout Sweden, representing different geographical and socio-economic areas. The aim of this study was to collect and evaluate self-reported injuries and associated factors during various physical activities as recalled retrospectively for 3 months by the students. Every sixth student (n=299 or 16%) reported 306 injuries. Twice as many girls than boys were injured during physical education class. Ninth-grade students reported relatively more injuries during organized sports than during physical education class and leisure activities. There were no age or gender differences in incidence rate during leisure activities. Most injuries were minor, as 70% were back in physical activity within a week. Half of the students (50%) reported that they previously had injured the same body part. Primary care of the injured student was, with the exception of a family member, most often carried out by the physical education teacher or coach, which accentuates the importance of continuous sports medicine first aid education for this group.

  • 50. Tokuno, C D
    et al.
    Cresswell, A G
    Thorstensson, Alf
    Gymnastik- och idrottshögskolan, GIH, Institutionen för idrotts- och hälsovetenskap, Laboratoriet för biomekanik och motorisk kontroll (BMC).
    Carpenter, M G
    Recruitment order of the abdominal muscles varies with postural task.2013Inngår i: Scandinavian Journal of Medicine and Science in Sports, ISSN 0905-7188, E-ISSN 1600-0838, Vol. 23, nr 3, s. 349-54Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Abdominal muscle recruitment strategies in response to a postural perturbation contradict the theory that the deeper abdominal muscles are always recruited in advance of the more superficial muscles. The purpose of this study was to determine whether such contrasting muscle recruitment patterns are due to the postural task or the predictability of a postural task. Participants performed an arm raise task as well as an unpredictable and a predictable balance perturbation task (i.e. support-surface translation) while intramuscular electromyographic (EMG) recordings were obtained from the deep [transversus abdominis (TrA)] and superficial [obliquus externus (OE)] abdominal muscles. The abdominal muscle recruitment order was dependent on the postural task but not on the predictability of a postural perturbation. Whereas arm raises elicited similar EMG onset latencies in TrA and OE, the OE onset latency was 48 ms earlier than the TrA following an unpredictable translation (P = 0.003). The early OE activation persisted when the translation was made predictable to the participant (P = 0.024). These results provide evidence that the abdominal muscle recruitment order varies with the trunk stability requirements specific to each task. Rehabilitation strategies focusing on an early TrA activation to improve postural stability may not be appropriate for all everyday tasks.

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