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  • 351.
    Lindgren, Martin
    et al.
    Department of Molecular and Clinical Medicine, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Sahlgrenska University Hospital/Östra.
    Börjesson, Mats
    Department of Food, Nutrition and Sports Science, Institute of Neuroscience and Physiology, Sahlgrenska Academy and, Sahlgrenska University Hospital/Östra.
    Ekblom, Örjan
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Åstrand Laboratory of Work Physiology, Björn Ekblom's and Mats Börjesson's research group.
    Bergström, Göran
    Department of Molecular and Clinical Medicine, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Sahlgrenska University Hospital/Östra.
    Lappas, Georgios
    Department of Molecular and Clinical Medicine, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Sahlgrenska University Hospital/Östra.
    Rosengren, Annika
    Department of Molecular and Clinical Medicine, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Sahlgrenska University Hospital/Östra.
    Physical activity pattern, cardiorespiratory fitness, and socioeconomic status in the SCAPIS pilot trial — A cross-sectional study2016In: Preventive Medicine Reports, ISSN 0350-1159, E-ISSN 2211-3355, Vol. 4, p. 44-49Article in journal (Refereed)
    Abstract [en]

    Living in a low socioeconomic status (SES) area is associated with an increased risk of cardiovascular events and all-cause mortality. Previous studies have suggested a socioeconomic gradient in daily physical activity (PA), but have mainly relied on self-reported data, and individual rather than residential area SES. This study aimed to investigate the relationships between residential area SES, PA pattern, compliance with PA-recommendations and fitness in a Swedish middle-aged population, using objective measurements. We included 948 individuals from the SCAPIS pilot study (Gothenburg, Sweden, 2012, stratified for SES, 49% women, median age: 58years), in three low and three high SES districts. Accelerometer data were summarized into intensity-specific categories: sedentary (SED), low (LIPA), and medium-to-vigorous PA (MVPA). Fitness was estimated by submaximal ergometer testing. Participants of low SES areas had a more adverse cardiovascular disease risk factor profile (smoking: 20% vs. 6%; diabetes: 9% vs. 3%; hypertension: 38% vs. 25%; obesity: 31% vs. 13%), and less frequently reached 150min of MVPA per week (67% vs. 77%, odds ratio [OR]=0.61; 95% confidence interval [95% CI]=0.46–0.82), from 10-minute bouts (19% vs. 31%, OR=0.53, 95% CI=0.39–0.72). Individuals in low SES areas showed lower PA levels (mean cpm: 320 vs. 348) and daily average MVPA (29.9 vs. 35.5min), and 12% lower fitness (25.1 vs. 28.5mL×min−1×kg−1) than did those in high SES areas. Reduced PA and fitness levels may contribute to social inequalities in health, and should be a target for improved public health in low SES areas.

  • 352.
    Lindkvist, Madelene
    et al.
    Örebro university.
    Fernberg, Ulrika
    Örebro university.
    Ljungberg, Liza U
    Örebro university.
    Fälker, Knut
    Örebro university.
    Fernström, Maria
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Åstrand Laboratory of Work Physiology. Örebro university.
    Hurtig-Wennlöf, Anita
    Örebro university.
    Grenegård, Magnus
    Örebro university.
    Individual variations in platelet reactivity towards ADP, epinephrine, collagen and nitric oxide, and the association to arterial function in young, healthy adults.2019In: Thrombosis Research, ISSN 0049-3848, E-ISSN 1879-2472, Vol. 174, p. 5-12, article id S0049-3848(18)30647-9Article in journal (Refereed)
    Abstract [en]

    INTRODUCTION: Platelet aggregation and secretion can be induced by a large number of endogenous activators, such as collagen, adenosine diphosphate (ADP) and epinephrine. Conversely, the blood vessel endothelium constitutively release platelet inhibitors including nitric oxide (NO) and prostacyclin. NO and prostacyclin are also well-known vasodilators and contribute to alterations in local blood flow and systemic blood pressure.

    MATERIALS AND METHODS: In this study we investigated individual variations in platelet reactivity and arterial functions including blood pressure and flow-mediated vasodilation (FMD) in 43 young, healthy individuals participating in the Lifestyle, Biomarkers and Atherosclerosis (LBA) study. Platelet aggregation and dense granule secretion were measured simultaneously by light transmission and luminescence. FMD was measured with ultrasound.

    RESULTS: The platelet function assay showed inter-individual differences in platelet reactivity. Specifically, a sub-group of individuals had platelets with an increased response to low concentrations of ADP and epinephrine, but not collagen. When the NO-donor S-nitroso-N-acetyl-DL-penicillamine (SNAP) was combined with high doses of these platelet activators, the results indicated for sub-groups of NO-sensitive and NO-insensitive platelets. The individuals with NO-sensitive platelets in response to SNAP in combination with collagen had a higher capacity of FMD of the arteria brachialis.

    CONCLUSIONS: Platelet reactivity towards ADP, epinephrine and NO differs between young, healthy individuals. Some individuals have a more effective response towards NO, both in the aspect of platelet inhibition ex vivo, as well as vasodilation in vivo.

  • 353. Lindwall, Magnus
    et al.
    Gerber, Markus
    Jonsdottir, Ingibjörg H
    Börjesson, Mats
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Åstrand Laboratory of Work Physiology, Björn Ekblom's and Mats Börjesson's research group.
    Ahlborg, Gunnar
    The relationships of change in physical activity with change in depression, anxiety, and burnout: A longitudinal study of Swedish healthcare workers.2014In: Health Psychology, ISSN 0278-6133, E-ISSN 1930-7810, Vol. 33, no 11, p. 1309-1318Article in journal (Refereed)
    Abstract [en]

    Objective: The purpose of the present study was to examine whether intraindividual changes in physical activity were correlated with intraindividual changes in mental health (depression, anxiety, and burnout) across four measurement time-points over 6 years, both from between-person and within-person perspectives. Methods: Health care workers (N = 3717; mean age = 46.9; SD = 10.0) were the target population in this study, which is part of a larger longitudinal survey that included questionnaires on physical activity levels and mental health (depression, anxiety, and burnout) at four time points across 6 years (2004-2010). Physical activity was assessed with an adapted version of the widely used 1-item, 4-level Saltin Grimby Physical Activity Level Scale (SGPALS). Depression, anxiety, and burnout were assessed using the Hospital Anxiety and Depression (HAD) scale and the Shirom-Melamed Burnout Questionnaire (SMBQ). Bivariate latent growth curve models were used to analyze the associations of change between physical activity and mental health. Results: Baseline levels of physical activity were moderately associated with baseline levels of mental health (rs = -.27 to -.40, ps < .01). Changes in physical activity were moderately to strongly associated (rs = -.57 to -.79, ps <. 01) with change in mental health at the between-person (correlated change) level and significantly, but weakly (rs = -.08 to -.14, ps <.01), associated with change at the within-person (coupled change) level of analysis. Conclusions: Changes in physical activity were associated with, and traveled together with, changes in depression, anxiety, and burnout across time. Changes in physical activity, and not only current or previous levels of activity, may be important to consider in preventive work linked to mental health within this population. (PsycINFO Database Record (c) 2014 APA, all rights reserved).

  • 354.
    Lundvall, Suzanne
    et al.
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Forskningsgruppen för pedagogik, idrott och fritidskultur.
    Schantz, Peter
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Åstrand Laboratory of Work Physiology, The Research Unit for Movement, Health and Environment.
    200 years of physical education teacher education: An overview of movement practices2016In: Researching Embodied Sport: Exploring Movement Cultures / [ed] Ian Wellard, Oxon, England: Routledge, 2016, p. 30-46Chapter in book (Other academic)
  • 355.
    Lundvall, Suzanne
    et al.
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Forskningsgruppen för pedagogik, idrott och fritidskultur.
    Schantz, Peter
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, The Research Unit for Movement, Health and Environment.
    A 200-year perspective and future challenges: Physical activities and their relation to physical education2013In: Gender In Physical Culture The 2013 Meeting: Transnational working group for the study of gender and sport, 2013Conference paper (Other academic)
    Abstract [en]

    Over time the chosen bodily movement practices within Physical education and health (PEH) have created tensions in terms of power and control over what has been seen as legitimate in the educational sector of physical culture. The aim of the study has been to, through a macro level overview and by using a model, illuminate how different bodily movement practices in the world’s oldest physical education teacher education (PETE) have emerged over time, become embedded, remain, fade or disappear. By following this continuity and discontinuity of practices, four distinct phases have been identified and their contextual background is described.

    The theoretical departure point is inspired by the work of Bourdieu. The analytical focus have been placed on how deliberate forms of bodily movement practices within the studied PETE program came to be defined and regulated through meaning making principles, or in other words: logic of practices (Bourdieu 1984, 1990). This departure point makes it possible to analyze how aspects of investment and intrinsic values have been put forward and related to views on body, gender and health.

    Findings: The first phase is characterized by the establishment of Ling gymnastics from early 1800s, and its gradual fall in the 1900s. Next phase started in the late 1800s and dealt with the introduction of sport and outdoor life. The third relates to the rise and fall of a separate female gymnastics practice during the 1900s. The fourth phase is characterized by the introduction of everyday life physical activities in the beginning of the new millennium. The overview is followed by reflections on the future content of bodily movement practices and sought for values in PETE and physical education in the school system, seen from a gender perspective.

  • 356.
    Lundvall, Suzanne
    et al.
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Forskningsgruppen för pedagogik, idrott och fritidskultur.
    Schantz, Peter
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Åstrand Laboratory of Work Physiology, The Research Unit for Movement, Health and Environment.
    Physical Activities and Their Relation to Physical Education: A 200-Year Perspective and Future Challenges2013In: The Global Journal of Health and Physical Education Pedagogy, ISSN 2160-2570, Vol. 2, no 1, p. 1-16Article in journal (Refereed)
    Abstract [en]

    In this macrolevel overview, a model of the multiplicity of the field of bodily movement cultures is initially presented. The model is then used to illuminate how different bodily movement practices emerged over time, became embedded, remained, faded, or disappeared in the world’s oldest physical education teacher education (PETE) program. Through thiscontinuity and discontinuity of practices, five distinct phases are identified, although sometimes intertwined, and their contextual background is described. The first phase is characterized by the establishment of Ling gymnastics from the early 19thcentury and by its fall in the 20thcentury. The next phase started in the late 19thcentury and dealt with the introduction of sportsand outdoor life. During a third phase, sports became the dominating movement practice. The fourth phase is related to the rise and fall of a separate female gymnastics culture during the 20thcentury. The fifth phase is characterized by the introduction of everyday life physical activities at the beginning of the new millennium. The overview is followed by reflections on the future content of bodily movement practices and sought-after values in PETE and physical education in the school system.

  • 357. Löllgen, H.
    et al.
    Börjesson, Mats
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Åstrand Laboratory of Work Physiology, Björn Ekblom's and Mats Börjesson's research group.
    Cummiskey, J.
    Bachl, N.
    Debruyne, A.
    The Pre-Participation Examination in Sports: EFSMA Statement on ECG for Pre-Particpation Examination: Die sportärztliche Vorsorgeuntersuchung : Stellungnahme der EFSMA zur Bedeutung des EKG in der Vorsorgeuntersuchung2015In: Deutsche Zeitschrift für Sportmedizin, ISSN 0344-5925, Vol. 66, no 6, p. 151-155Article in journal (Refereed)
    Abstract [en]

    Goals of pre-participation examination (PPE) in athletes are primarily to protect health of athletes. This applies for children, adolescents, leisure time and top athletes. To recognise early possible risks, history and clinical examination is agreed to be the basis of PPE. However, there is a long-standing  controversy about whether ECG at rest should also be mandatory for all athletes. ECG is rejected in the US but included in most European countries.

    In addition, some large sports organisations also require ECG in PPE of athletes. The resting ECG can detect potential life-threatening diseases such as cardiomyopathies or ion-channel diseases ,thus avoiding sudden cardiac events or even death. The present paper discusses many arguments pro and contra ECG in athlete's screening. Arguments against are organisational problems, as sports physicians are not present nationwide in the US. Main arguments against are the lack of large prospective studies demonstrating reduced mortality by ECG, and the low sensitivity, specificity and predictive values of the ECG.

    However, current studies, new stringent and reliable criteria for ECG interpretation (e.g. Seattle criteria) increased the validity: false positive and negative findings decrease significantly. This is also supported by new, athlete-related ECG interpretation software in ECG devices, which are more reliable than visual analysis. This also may reduce legal problems, whereas psychological problems are of low importance as has been shown recently. Therefore, ECG recording in all athletes is strongly recommended in Europe. ECG is superior to history and clinical exam in detecting hidden and congenital diseases.

    However, special education in sports cardiology is advised, courses and training in ECG interpretation in athletes, as well as special ECG devices are mandatory for correct ECG interpretation in athletes.

  • 358.
    Lönnberg, Lena
    et al.
    Uppsala University, Sweden..
    Ekblom Bak, Elin
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Åstrand Laboratory of Work Physiology, Björn Ekblom's research group.
    Damberg, Mattias
    Uppsala University, Sweden..
    Improved unhealthy lifestyle habits in patients with high cardiovascular risk: results from a structured lifestyle programme in primary care2019In: Upsala Journal of Medical Sciences, ISSN 0300-9734, E-ISSN 2000-1967, Vol. 124, no 2, p. 94-104Article in journal (Refereed)
    Abstract [en]

    Background. Physical activity, healthful dietary habits, and not smoking are associated with reduced cardiovascular morbidity and mortality. However, few studies have examined how counselling to improve poor lifestyle habits might be carried out in clinical practice. In Swedish primary care, structured lifestyle counselling is still not integrated into everyday clinical practice. The aim of the present study was two-fold: (1) to describe a novel lifestyle intervention programme in primary care; and (2) to evaluate change in unhealthy lifestyle habits over 1 year in men and women with high cardiovascular risk who participated in the lifestyle intervention programme. Method. A single-group study with a 1-year follow-up was carried out. A total of 417 people was enrolled, median age 62 years (54% women), with either hypertension (69%), type 2 diabetes mellitus, or impaired glucose tolerance. The 1-year intervention included five counselling sessions that focused on lifestyle habits, delivered by a district nurse with postgraduate credits in diabetes care and the metabolic syndrome. All patients were offered in-depth counselling for one or more lifestyle habits when needed. Lifestyle habits were assessed by a questionnaire at baseline and 1-year follow-up. Total change was assessed using a nine-factor unhealthy lifestyle habit index. Results. Favourable, significant changes were observed for physical activity, dietary habits, smoking, and stress over 1 year. Similar improvements were seen for both sexes and type of diagnosis. Conclusions. The results support the utility of a multifactorial, structured approach to change unhealthy lifestyle habits for cardiovascular risk prevention in a primary care setting.

  • 359. Lövenheim, Boel
    et al.
    Johansson, Christer
    Wahlgren, Lina
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Åstrand Laboratory of Work Physiology, The Research Unit for Movement, Health and Environment. Riksidrottsförbundet.
    Rosdahl, Hans
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Åstrand Laboratory of Work Physiology, The Research Unit for Movement, Health and Environment.
    Salier Eriksson, Jane
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Åstrand Laboratory of Work Physiology, The Research Unit for Movement, Health and Environment.
    Schantz, Peter
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Åstrand Laboratory of Work Physiology, The Research Unit for Movement, Health and Environment.
    Almström, Peter
    Berglund, Svante
    Markstedt, Anders
    Nilsson Sommar, Johan
    Forsberg, Bertil
    Health risk assessment of reduced air pollution exposure when changing commuting by car to bike2016Conference paper (Refereed)
    Abstract [en]

    In this study we have assessed the reduction in traffic emissions and population exposure assuming all potential car commuters would switch to biking if they live within 30 minute travel by bike. The scenario would result in more than 100 000 new bikers and due to the reduced traffic emissions 42 premature deaths would be avoided per year. This is almost twice as large effect as the congestion tax in Stockholm.

     

     

    Introduction

    Regular physical activity has important and wide-ranging health benefits including reduced risk of chronic disease, and physical inactivity is mentioned as perhaps the most important public health problem of the 21st century. At the same time, the direct effects of traffic emissions is a major health problem. Transferring commuting by car to bike will increase physical activity and reduce emissions and reduce population exposure to traffic pollution. The exposure of commuters will also change; new bikers may get higher exposure whilst old bikers and car drivers may get lower exposures, depending on commuting route and distance.

     

    Methodology

    In this study we have calculated the potential number of car-to-bike switching commuters depending on distance, travel time, age of commuters, etc. We have made calculations for a 30-minute biking scenario, i.e. transferring all car commuters to bike if their travel time by bike is less than or equal to 30 minutes. The commuting distance depends on age and sex. For the travel and traffic modelling the LuTrans model was used. It includes all different modes of travel; walking, bicycling, public transport systems and car traffic. The model was developed based on travel survey data and is regularly calibrated using traffic counts. Emissions from road traffic were calculated based on HBEFA 3.2. A Gaussian dispersion model was used estimate exposures over the county of Stockholm.

     

    Results

    The 30 min scenario resulted in 106 881 more bikers, an increase of 2.6 times compared to base scenario. Of all bikers 50% were men and the mean age of all bikers was 42. The traffic emissions of NOx was reduced by up to 7%. Up to 20% reduction in traffic contribution to NOx concentrations was calculated as shown in Figure 1. The mean reduction in concentration for the whole area is 6% and the largest occur were most people live.

    The population weighted mean NOx concentration for 1.6 million people in Greater Stockholm is estimated to be reduced by 0.41 μg m-3. Assuming that the premature mortality is reduced by 8% per 10 μg m-3 (Nafstad et al., 2004), this corresponds to 42 avoided premature deaths every year or 514 gained life years gained. This is even somewhat more beneficial than the effects of the congestion charge in Stockholm (Johansson et al., 2009), which was estimated to save 27 premature deaths per year. The gain in reduced mortality is almost as large as the gain in health of the increased physical activity.

     

    Conclusions

    Transferring car commuters to bike is not only beneficial for the physical activity, but will also lead to reduced traffic emissions and reduced population exposure. Our estimates show that it may be even more beneficial for mortality due to air pollution exposure than the congestion charge in Stockholm.

     

    Acknowledgement

    This project was funded by the Swedish Research Council for Health, Working life and Welfare.

     

    References

    Johansson, C., Burman, L., Forsberg, B. 2009. The effects of congestions tax on air quality and health. Atmos. Environ. 43, 4843-4854.

    Nafstad, P., Lund Håheim, L., Wisloeff, T., Gram, G., Oftedal, B., Holme, I., Hjermann, I. and Leren, P. 2004. Urban Air Pollution and Mortality in a Cohort of Norwegian Men. Environ. Health Perspect. 112, 610-615.

  • 360. Malm, Christer
    et al.
    Ekblom, Örjan
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Björn Ekblom's research group.
    Ekblom, Björn
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Björn Ekblom's research group.
    Immune system alteration in response to increased physical training during a five day soccer training camp.2004In: International Journal of Sports Medicine, ISSN 0172-4622, E-ISSN 1439-3964, Vol. 25, no 6, p. 471-6Article in journal (Refereed)
    Abstract [en]

    Leukocyte and monocyte subpopulations were investigated in ten elite male soccer players before and after a 5-day training camp. It was hypothesized that with increased training intensity and duration, the immune system would show signs of depression. Blood samples were taken at rest before and after the training camp and cell surface antigens were investigated by four-colour flow cytometry. After five days of intensified training, there was a significant decrease in the number of T helper, T cytotoxic and B cells, the expression of CD11 b on leukocytes increased and the NK cell population did not change significantly. It is concluded that after a period of intensified training, soccer players may experience decreased T and B cell numbers in circulation, possibly affecting their capability to activate the immune system and resist infections. However, in contrast to the acute decrease in the number of circulating NK cells commonly observed after physical exercise, no change in this cell population was observed at rest after a period of intensified physical training. Exercise-induced immunological changes were highly differentiated between different leukocyte subpopulations.

  • 361. Malm, Christer
    et al.
    Ekblom, Örjan
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Björn Ekblom's research group.
    Ekblom, Björn
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Björn Ekblom's research group.
    Immune system alteration in response to two consecutive soccer games.2004In: Acta Physiologica Scandinavica, ISSN 0001-6772, E-ISSN 1365-201X, Vol. 180, no 2, p. 143-55Article in journal (Refereed)
    Abstract [en]

    AIM: Changes in leucocyte and monocyte subpopulations were investigated in 10 elite male soccer players aged 16-19 years. The purpose was to perform a descriptive study of immunological alterations in elite soccer players in response to two consecutive games separated by 20 h. It was hypothesized that in response to two games the players would show signs of short-term immunosuppression. METHODS: Blood samples were taken before the first soccer game, immediately after the second game and after 6, 24, 48 and 72 h. Cell surface antigens, testosterone and cortisol were investigated. RESULTS: During the first 6 h after the second game there was a significant increase in number of circulating neutrophils, mature (CD20+ CD5+) B cells and CD4/CD8 ratio. A significant decrease was observed in the number of natural killer (NK) cells, monocytes and adhesion on lymphocytes and monocytes. In a delayed phase, 48 h after the second game the expression of both adhesion and signalling molecules increased on lymphocytes and monocytes. Changes in adhesion and signalling molecules at 48 h correlated negatively to the subjects VO2max, suggesting larger immunological response to similar exercise in subjects with lower aerobic exercise capacity. CONCLUSION: In response to competitive soccer exercise some immunological variables are enhanced while others are depressed. Observed changes may serve a purpose in adaptation to exercise by signalling via adhesion.

  • 362. Malm, Christer
    et al.
    Ekblom, Örjan
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Björn Ekblom's research group.
    Ekblom, Björn
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Björn Ekblom's research group.
    Immunological Alterations Used to Predict Infections in Response to Strenuous Physical Training2011In: Military medicine, ISSN 0026-4075, E-ISSN 1930-613X, Vol. 176, no 7, p. 785-790Article in journal (Refereed)
    Abstract [en]

    ABSTRACT The aim of this study was to screen leukocyte cell surface markers to identify possible predictors for infection related to physical training. Ten healthy soldiers (mean age, 19.1; mean body mass, 77.4 kg; mean VO ^sub 2^ peak, 4.54 L min ^sup -1^ /58.6 mL min ^sup -1^ kg ^sup -1^ ) were included. Blood samples were collected and number of infections recorded before and after a 6-day training course. White blood cell distributions and expression of surface receptors changed during training. Before training, expression of CD3 on CD8  lymphocytes and percent CD8 CD3 lymphocytes was lower, whereas CD4/CD8 ratio was higher among subjects who failed compared to those who completed the training. A subclinical infection before the start of the military training may alter the CD4/CD8 ratio. Prediction of future infections may be possible from pre-exercise immunological status, fi ndings useful in military settings and exercise, where sudden infections may result in severe consequences.  

  • 363. Malm, Christer
    et al.
    Sjödin, The Late Bertil
    Sjöberg, Berit
    Lenkei, Rodica
    Renström, Per
    Lundberg, Ingrid E
    Ekblom, Björn
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Björn Ekblom's research group.
    Leukocytes, cytokines, growth factors and hormones in human skeletal muscle and blood after uphill or downhill running.2004In: Journal of Physiology, ISSN 0022-3751, E-ISSN 1469-7793, Vol. 556, no Pt 3, p. 983-1000Article in journal (Refereed)
    Abstract [en]

    Muscular adaptation to physical exercise has previously been described as a repair process following tissue damage. Recently, evidence has been published to question this hypothesis. The purpose of this study was to investigate inflammatory processes in human skeletal muscle and epimysium after acute physical exercise with large eccentric components. Three groups of subjects (n= 19) performed 45 min treadmill running at either 4 deg (n= 5) or 8 deg (n= 9) downhill or 4 deg uphill (n= 5) and one group served as control (n= 9). One biopsy was taken from each subject 48 h post exercise. Blood samples were taken up to 7 days post exercise. Compared to the control group, none of the markers of inflammation in muscle and epimysium samples was different in any exercised group. Only subjects in the Downhill groups experienced delayed onset of muscle soreness (DOMS) and increased serum creatine kinase activity (CK). The detected levels of immunohistochemical markers for T cells (CD3), granulocytes (CD11b), leukaemia inhibitory factor (LIF) and hypoxia-inducible factor 1beta (HIF-1beta) were greater in epimysium from exercised subjects with DOMS ratings >3 (0-10 scale) compared to exercised subjects without DOMS but not higher than controls. Eccentric physical exercise (downhill running) did not result in skeletal muscle inflammation 48 h post exercise, despite DOMS and increased CK. It is suggested that exercise can induce DOMS by activating inflammatory factors present in the epimysium before exercise. Repeated physical training may alter the content of inflammatory factors in the epimysium and thus reduce DOMS.

  • 364. Mandroukas, A
    et al.
    Heller, J
    Metaxas, T I
    Christoulas, K
    Vamvakoudis, E
    Stefanidis, P
    Papavasileiou, A
    Kotoglou, K
    Balasas, D
    Ekblom, Björn
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Björn Ekblom's research group.
    Mandroukas, K
    Deltoid muscle characteristics in wrestlers.2010In: International Journal of Sports Medicine, ISSN 0172-4622, E-ISSN 1439-3964, Vol. 31, no 3, p. 148-53Article in journal (Refereed)
    Abstract [en]

    The purpose of the present study was to investigate the deltoid muscle characteristics of wrestlers. Nine Greco-Roman competitive male wrestlers (mean age 20.1+/-2.7 yrs, height 175+/-0.6 cm, weight 83.2+/-12.5 kg, years of training 7.6+/-2.7 yrs) participated in this study. Six male healthy sedentary students (mean age 21.2+/-0.9 yrs, height 180+/-0.3 cm, weight 80.1+/-9.4 kg) served as controls. Muscle fibre distribution, cross-sectional area (CSA), as well as satellite cells, myonuclei and capillary density per muscle fibre area were determined by immunohistochemistry. Myosin heavy chain MHC isoform composition of single fibres was determined with protein electrophoresis. Immunohistochemical analysis showed that muscle fibre distribution of the MHC I and IIA were significantly higher in wrestlers than in controls (p<0.05). Electrophoretic analysis of single fibres revealed a significantly higher proportion of fibres containing MHC I and IIC in wrestlers (p<0.05). The mean CSA of type IIA fibres and the number of myonuclei per type II was significantly higher in wrestlers (p<0.05). We also found that the number of satellite cells was 2.5 fold higher in wrestlers than in the control group. This study suggests that the observed muscle fibre profile in the deltoid of wrestlers may represent an adaptation based on the specific mechanical and biochemical demands of the long-term training in Greco-Roman wrestling.

  • 365. Mandroukas, A
    et al.
    Metaxas, T
    Kesidis, N
    Christoulas, K
    Vamvakoudis, E
    Stefanidis, P
    Heller, J
    Ekblom, Björn
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Björn Ekblom's research group.
    Mandroukas, K
    Deltoid muscle fiber characteristics in adolescent and adult wrestlers.2010In: Journal of Sports Medicine and Physical Fitness, ISSN 0022-4707, E-ISSN 1827-1928, Vol. 50, no 2, p. 113-20Article in journal (Refereed)
    Abstract [en]

    Our findings suggest that the observed muscle fiber profile in the deltoid muscle of wrestlers may represent an adaptation based on the mechanical and biochemical demands of the long-term training. Such adaptations are linked to the specific characteristics of the training program, the level and the previous training experience of the wrestlers.

  • 366.
    Manselin, Tom A
    et al.
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Åstrand Laboratory of Work Physiology.
    Södergård, Olof
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Åstrand Laboratory of Work Physiology.
    Larsen, Filip J
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Åstrand Laboratory of Work Physiology, Research group for Mitokondriell funktion och metabolisk kontroll.
    Lindholm, Peter
    Karolinska institutet.
    Aerobic efficiency is associated with the improvement in maximal power output during acute hyperoxia.2017In: Physiological Reports, E-ISSN 2051-817X, Vol. 5, no 2, article id e13119Article in journal (Refereed)
    Abstract [en]

    This study investigated the relationship between aerobic efficiency during cycling exercise and the increase in physical performance with acute hyperoxic exposure (FiO2 ~31%) (HOX) and also tested the hypothesis that fat oxidation could be increased by acute hyperoxia. Fourteen males and four females were recruited for two sessions, where they exercised for 2 × 10 min at 100 W to determine efficiency. HOX and normoxia (NOX) were administered randomly on both occasions to account for differences in nitrogen exchange. Thereafter, a progressive ramp test was performed to determine VO2max and maximal power output (Wmax). After 30 min rest, workload was set to 80% of maximal power output (Wmax) for a time to exhaustion test (TTE). At 100W gross efficiency was reduced from 19.4% during NOX to 18.9% during HOX (P ≤ 0.0001). HOX increased fat oxidation at 100 W by 52% from 3.41 kcal min(-1) to 5.17 kcal min(-1) (P ≤ 0.0001) with a corresponding reduction in carbohydrate oxidation. Wmax increased by 2.4% from 388.8 (±82.1) during NOX to 397.8 (±83.5) during HOX (P ≤ 0.0001). SaO2 was higher in HOX both at the end of the maximal exercise test and TTE. Subjects with a high level of efficiency in NOX had a larger improvement in Wmax with HOX, in agreement with the hypothesis that an optimum level of efficiency exists that maximizes power production. No association between mitochondrial excess capacity and endurance performance was found; increases in oxygen supply seemed to increase maximal aerobic power production and maintain/increase endurance capacity at the same relative workload.

  • 367.
    Marcus, Moberg
    et al.
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Åstrand Laboratory of Work Physiology, Eva Blomstrand's research group.
    Apró, William
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Åstrand Laboratory of Work Physiology, Eva Blomstrand's research group.
    Ekblom, Björn
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Åstrand Laboratory of Work Physiology, Björn Ekblom's and Mats Börjesson's research group.
    van Hall, Gerrit
    Holmberg, Hans-Christer
    Blomstrand, Eva
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Åstrand Laboratory of Work Physiology, Eva Blomstrand's research group.
    Lower body endurance exercise acutely affects resistance exercise induced transcriptional and translational signalling in the tricpes brachii muscleManuscript (preprint) (Other academic)
  • 368. Marklund, Peter
    et al.
    Mattsson, C. Mikael
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences.
    Wåhlin-Larsson, Britta
    Ponsot, Elodie
    Lindvall, Björn
    Lindvall, Lisbeth
    Ekblom, Björn
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Björn Ekblom's research group.
    Kadi, Fawzi
    Extensive inflammatory cell infiltration in human skeletal muscle in response to an ultra-endurance exercise bout in experienced athletes.2013In: Journal of applied physiology, ISSN 8750-7587, E-ISSN 1522-1601, Vol. 114, no 1, p. 66-72Article in journal (Refereed)
    Abstract [en]

    The impact of a 24h ultra-endurance exercise bout on systemic and local muscle inflammatory reactions was investigated in nine experienced athletes. Blood and muscle biopsies were collected before (PRE), immediately after the exercise (POST) and after 28h of recovery (POST28). Circulating blood levels of leukocytes, CK, CRP and selected inflammatory cytokines were assessed together with the evaluation of the occurrence of inflammatory cells (CD3(+), CD8(+), CD68(+)) and the expression of major histocompatibility complex class-I (MHC class-I) in skeletal muscle. An extensive inflammatory cell infiltration occurred in all athletes and the number of CD3(+), CD8(+) and CD 68(+) cells were 2-3 fold higher at POST28 compared to PRE (P<0.05). The inflammatory cell infiltration was associated with a significant increase in the expression of MHC class-I in muscle fibers. There was a significant increase in blood leukocyte count, IL-6, IL-8, CRP and CK at POST. At POST28 total leukocytes, IL-6 and CK had declined, whereas IL-8 and CRP continued to increase. Increases in IL-1β and TNF-α were not significant. There were no significant associations between the magnitude of the systemic and local muscle inflammatory reactions. Signs of muscle degenerative and regenerative events were observed in all athletes with various degrees of severity and were not affected by the ultra-endurance exercise bout. In conclusion, a low-intensity but very prolonged single endurance exercise bout can generate a strong inflammatory cell infiltration in skeletal muscle of well-trained experienced ultra-endurance athletes, and the amplitude of the local reaction is not proportional to the systemic inflammatory response.

  • 369.
    Mascher, Henrik
    et al.
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Eva Blomstrand's research group.
    Andersson, H
    Nilsson, P-A
    Ekblom, Björn
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Björn Ekblom's research group.
    Blomstrand, Eva
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Eva Blomstrand's research group.
    Changes in signalling pathways regulating protein synthesis in human muscle in the recovery period after endurance exercise.2007In: Acta Physiologica, ISSN 1748-1708, E-ISSN 1748-1716, Vol. 191, no 1, p. 67-75Article in journal (Refereed)
    Abstract [en]

    AIM: Exercise induced alterations in the rate of muscle protein synthesis may be related to activity changes in signalling pathways involved in protein synthesis. The aim of the present study was to investigate whether such changes in enzyme phosphorylation occur after endurance exercise. METHODS: Six male subjects performed ergometer cycling exercise for 1 h at 75% of the maximal oxygen uptake. Muscle biopsy samples from the vastus lateralis were taken before, immediately after, 30 min, 1 h, 2 h and 3 h after exercise for the determination of protein kinase B (PKB/Akt), mammalian target of rapamycin (mTOR), glycogen synthase 3 kinase (GSK-3), p70S6 kinase (p70(S6k)) and eukaryotic elongation factor 2 (eEF2) phosphorylation. RESULTS: The phosphorylation of Akt was unchanged directly after exercise, but two- to fourfold increased 1 and 2 h after the exercise, whereas GSK-3alpha and beta phosphorylation were two- to fourfold elevated throughout most of the 3-h recovery period. Phosphorylation of mTOR was elevated threefold directly after, 30 min and 2 h after exercise and eEF2 phosphorylation was decreased by 35-75% from 30 min to 3 h-recovery. Exercise led to a five- to eightfold increase in Ser(424)/Thr(421) phosphorylation of p70(S6k) up to 30 min after exercise, but no change in Thr(389) phosphorylation. CONCLUSIONS: The marked decrease in eEF2 phosphorylation suggests an activation of translation elongation and possibly protein synthesis in the recovery period after sustained endurance exercise. The lack of p70(S6k) activation suggests that translation initiation is activated via alternative pathways, possibly via the activation of eukaryotic initiating factor 2B.

  • 370.
    Mascher, Henrik
    et al.
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Eva Blomstrand's research group.
    Ekblom, Björn
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Björn Ekblom's research group.
    Rooyackers, Olav
    Blomstrand, Eva
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Eva Blomstrand's research group.
    Enhanced rates of muscle protein synthesis and elevated mTOR signalling following endurance exercise in human subjects.2011In: Acta Physiologica, ISSN 1748-1708, E-ISSN 1748-1716, Vol. 202, no 2, p. 175-84Article in journal (Refereed)
    Abstract [en]

    AIM: The major aim of this study was to determine the fractional rate of protein synthesis (FSR) during the early period of recovery after intensive aerobic exercise in the absence of nutritional supplementation.

    METHODS: Sixteen male subjects performed one-legged cycling exercise for 1 h at approx. 65-70% of their one-legged maximal oxygen uptake. Using the stable isotope technique, the FSR in the vastus lateralis of both legs were determined during two periods, 0-90 min (n = 8) and 90-180 min (n = 8) after exercise. Biopsies were taken from both exercising and resting muscle before exercise, immediately after and following 90 or 180 min of recovery.

    RESULTS: During the initial 90 min of recovery, FSR in the exercising muscle tended to be higher than in the resting muscle (1.57 ± 0.12 vs. 1.44 ± 0.07% 24 h(-1); P = 0.1) and was significantly higher during the period 90-180 min after exercise (1.74 ± 0.14 vs. 1.43 ± 0.12% 24 h(-1) ; P < 0.05). Exercise induced a 60% increase (P < 0.05) in phosphorylation of mTOR and a fivefold increase (P < 0.05) in Thr(389) phosphorylation of p70S6 kinase as well as a 30% reduction (P < 0.05) in phosphorylation of eEF2. Phosphorylation of AMP-activated protein kinase was enhanced by 40% (P < 0.05) after exercise, but no significant effect on phosphorylation of Akt, or eIF2Bε was observed immediately after exercise.

    CONCLUSION: These findings indicate that during the first 3 h of recovery after intensive endurance exercise FSR gradually increases. Moreover, a stimulation of the mTOR-signalling pathway may be at least partially responsible for this elevated protein synthesis.

  • 371.
    Mascher, Henrik
    et al.
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Eva Blomstrand's research group.
    Tannerstedt, Jörgen
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Eva Blomstrand's research group.
    Blomstrand, Eva
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Eva Blomstrand's research group.
    Nya aspekter på aminosyrors roll i den muskulära anpassningen till träning2006In: Svensk Idrottsforskning: Organ för Centrum för Idrottsforskning, ISSN 1103-4629, Vol. 15, no 3, p. 56-60Article in journal (Other academic)
    Abstract [sv]

    Sammanfattningsvis kan sägas att tillgängligheten av protein/aminosyror är nödvändig för den muskulära anpassningen till träning vid både styrke- och uthållighetsträning. Betydligt fler studier har undersökt effekterna på styrketräning, men vid båda typer av träning är dock kunskaperna om de bakomliggande mekanismerna ännu så länge små. Genom den omfattande forskning som pågår inom området kommer med all säkerhet de molekylära och cellulära förändringar som sker i samband med träning att kartläggas inom en relativt snar framtid. Därmed öppnas nya möjligheter att förbättra och optimera träningen, t.ex. genom kombination av olika typer av aktiviteter (uthållighet och styrketräning). Denna kunskap är också avgörande för att förstå och eventuellt kunna påverka träningseffekten genom förändringar i nutritionens sammansättning.

  • 372.
    Mascher, Henrik
    et al.
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Eva Blomstrand's research group.
    Tannerstedt, Jörgen
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Eva Blomstrand's research group.
    Brink-Elfegoun, Thibault
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences.
    Ekblom, Björn
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Björn Ekblom's research group.
    Gustafsson, Thomas
    Blomstrand, Eva
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Eva Blomstrand's research group.
    Repeated resistance exercise training induces different changes in mRNA expression of MAFbx and MuRF-1 in human skeletal muscle.2008In: American Journal of Physiology. Endocrinology and Metabolism, ISSN 0193-1849, E-ISSN 1522-1555, Vol. 294, no 1, p. E43-51Article in journal (Refereed)
    Abstract [en]

    The gain in muscle mass as a result of resistance training is dependent on changes in both anabolic and catabolic reactions. A frequency of two to three exercise sessions per week is considered optimal for muscle gain in untrained individuals. Our hypothesis was that a second exercise session would enlarge the anabolic response and/or decrease the catabolic response. Eight male subjects performed resistance exercise on two occasions separated by 2 days. Muscle biopsies were taken from the vastus lateralis before and 15 min, 1 h, and 2 h after exercise. Exercise led to severalfold increases in phosphorylation of mTOR at Ser2448, p70 S6 kinase (p70S6k) at Ser424/Thr421 and Thr389, and ribosomal protein S6, which persisted for up to 2 h of recovery on both occasions. There was a tendency toward a larger effect of the second exercise on p70S6k and S6, but the difference did not reach statistical significance. The mRNA expression of MuRF-1, which increased after exercise, was 30% lower after the second exercise session than after the first one. MAFbx expression was not altered after exercise but downregulated 30% 48 h later, whereas myostatin expression was reduced by 45% after the first exercise and remained low until after the second exercise session. The results indicate that 1) changes in expression of genes involved in protein degradation are attenuated as a response to repetitive resistance training with minor additional increases in enzymes regulating protein synthesis and 2) the two ubiquitin ligases, MuRF-1 and MAFbx, are differently affected by the exercise as well as by repeated exercise.

  • 373.
    Mattsson, C. Mikael
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Åstrand Laboratory of Work Physiology, Björn Ekblom's and Mats Börjesson's research group.
    Factors determining ultra-endurance exercise performance2014Conference paper (Refereed)
    Abstract [en]

    This talk will focus on the major nutritional and physiological factors that influence ultra-endurance exercise performance in both recreational and elite athletes.

    Empirical observations show that athletes who have been engaged in ultra-endurance sports for several years have a large advantage compared to novices in the sport. It depends of course in part on the fact that they are more experienced, but even athletes from traditional endurance sports with a documented higher aerobic capacity (i.e., higher VO2max) have difficulties to keep up with ultra-endurance specialists when exercise duration exceeds three or four hours. This indicates that fatigue and performance in ultra-endurance exercise is determined by (in part) other factors compared to traditional endurance sports.

    Ultra-endurance sports vary in form and duration, such as running or adventure racing (AR) from 6 h to more than 6 days, but are no matter the nature of the specific competition still in many aspects extreme sports.

    The athletes do not generally need to perform at high maximum speeds, but the energy expenditure is extremely high. The total energy expenditure for a 24-h AR is approximately 18-20 000 kcal, which is almost 10 times more than normal basal metabolism (Enqvist et al. 2010). One reason for fatigue is that the energy deficit is substantial, also the profile of amino acids in blood and muscle change during races (Borgenvik et al. 2012), possibly contributing to the central fatigue that has been described in other studies.

    As for the physiological factors, our research group and collaborators have investigated many aspects of the versatile physiological adaptation to ultra-endurance exercise, such as circulatory adaptations and cardiac fatigue (Mattsson 2011, Mattsson et al. 2010, 2011) muscular damage (Wichardt et al 2011, Marklund et al 2013), hormonal status (Berg et al 2008), and immunological response (Wallberg et al 2011).

    The effect of sleep deprivation on both mental and physiological functions during the races must also be included in the total complex of factors limiting performance.

  • 374.
    Mattsson, C. Mikael
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Björn Ekblom's research group.
    Multisportens fysiologi2011In: Svensk Idrottsforskning: Organ för Centrum för Idrottsforskning, ISSN 1103-4629, Vol. 20, no 2, p. 50-53Article in journal (Other academic)
    Abstract [sv]

    Hur klarar kroppen flera dygn av tävling med relativt hög intensitet? Multisportare genomför sina lopp, men enligt traditionella fysiologiska förklaringsmodeller borde de ramla ihop av utmattning långt innan målgång. I vårt projekt ser vi hur kroppen och hjärtat istället anpassar sig till ansträngningarna utan några tecken på hjärtmuskelcellsskador.

  • 375.
    Mattsson, C. Mikael
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Åstrand Laboratory of Work Physiology, Björn Ekblom's and Mats Börjesson's research group.
    Physiology of Adventure Racing: with emphasis on circulatory response and cardiac fatigue2011Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The overall aims of this thesis were to elucidate the circulatory responses to ultra-endurance exercise (Adventure Racing), and furthermore, to contribute to the clarification of the so called “exercise-induced cardiac fatigue” in relation to said exercise. An Adventure race (AR) varies in duration from six hours to over six days, in which the participants have to navigate through a number of check-points over a pre-set course, using a combination of three or more endurance/outdoor sports, e.g., cycling, running, and kayaking. This thesis is based on the results from four different protocols; 12- and 24-h (n = 8 and 9, respectively) in a controlled setting with fixed exercise intensity, and 53-h and 5-7-day (n = 15 in each) in field setting under race conditions. The subjects in all protocols were experienced adventure racing athletes, competitive at elite level. Study I and II address the circulatory responses and cardiovascular drift, using methods for monitoring heart rate (HR), oxygen uptake (VO2), cardiac output (non-invasive re-breathing) and blood pressure, during ergometer cycling at fixed steady state work rate at periods before, during and after the ultra-endurance exercise. In Study III and IV we examined the possible presence of exercise-induced cardiac fatigue after a 5-7-day AR, from two different perspectives. In Study III analyses were performed with biochemical methods to determine circulating levels of cardiac specific biomarkers (i.e., creatine kinase isoenzyme MB (CK-MB), troponin I, B-type natriuretic peptide (BNP) and N-terminal prohormonal B-type natriuretic peptide (NT-proBNP)). We also made an attempt to relate increases in biomarkers to rated relative performance. In Study IV we used tissue velocity imaging (TVI) (VIVID I, GE VingMed Ultrasound, Norway) to determine whether the high workload (extreme duration) would induce signs of functional cardiac fatigue similar to those that occur in skeletal muscle, i.e., decreased peak systolic velocities. Using conventional echocardiography we also evaluated whether the hearts of experienced ultra-endurance athletes are larger than the normal upper limit. The central circulation changed in several steps in response to ultra-endurance exercise. Compared to initial levels, VO2 was increased at every time-point measured. The increase was attributed to peripheral adaptations, confirmed by a close correlation between change in VO2 and change in arteriovenous oxygen difference. The first step of the circulatory response was typical of normal (early) cardiovascular drift, with increased HR and concomitantly decreased stroke volume (SV) and oxygen pulse (VO2/HR), occurring over the first 4-6 h. The second step, which continued until approximately 12h, included reversed HR-drift, with normalisation of SV and VO2/HR. When exercise continued for 50 h a late cardiovascular drift was noted, characterised by increased VO2/HR, (indicating more efficient energy distribution), decreased peripheral resistance, increased SV, and decreased work of the heart. Since cardiac output was maintained at all-time points we interpret the changes as physiologically appropriate adaptations. Our findings in Study III point towards a distinction between the clinical/pathological and the physiological/exercise-induced release of cardiac biomarkers. The results imply that troponin and CKMB lack relevance in the (healthy) exercise setting, but that BNP, or NT-proBNP adjusted for exercise duration, might be a relevant indicator for impairment of exercise performance. High levels of NTproBNP, up to 2500 ng · l -1 , can be present after ultra-endurance exercise in healthy athletes without any subjective signs or clinical symptoms of heart failure. However, these high levels of NT-proBNP seemed to be associated with decreased relative exercise performance, and might be an indicator of the cardiac fatigue that has previously been described after endurance exercise. Study IV revealed that the sizes of the hearts (left ventricle) of all of our ultra-endurance athletes were within normal limits. The measurements of peak systolic velocities showed (for group average) no signs of cardiac fatigue even after 6 days of continuous exercise. This discrepancy between ours and other studies, involving e.g., marathon or triathlon, might reflect the fact that this type of exercise is performed at relatively low average intensity, suggesting that the intensity, rather than the duration, of exercise is the primary determinant of cardiac fatigue.

  • 376.
    Mattsson, C. Mikael
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Åstrand Laboratory of Work Physiology, Björn Ekblom's and Mats Börjesson's research group.
    Requirements for Soldiers’ Endurance Capacity in Prolonged Continuous Work2014Conference paper (Refereed)
    Abstract [en]

    Physiological factors that influence soldier’s ability to sustain performance level in prolonged continuous work are such as A) initial physical level; B) ability to carry; and C) ability to sustain performance level over prolonged periods of time.

    A) General fitness level is obviously crucial, such as strength and aerobic capacity, but so is also being completely healthy when the effort initiates. We have presented an immunological profile that might be useful to determine which soldiers that will underperform. Before a 6-day military training course expression of CD3 on CD8+ lymphocytes and percent CD8+CD3 lymphocytes was lower, whereas CD4/CD8 ratio was higher among soldiers who failed compared to those who completed the training (Ekblom et al. 2011).

    B) It is well know that energy expenditure increases with increased carried weight, but at heavier loads (>30 kg) we found a disproportionate increase. Our hypothesis is that this is due to inaccurate technique, caused by insufficient strength relative to the carried weight, which may lead to unusual tiredness. In our preliminary results all soldiers had a point, carried weight, above which the work economy decreased. Therefore, it would be relevant to determine each soldier’s maximum optimal weight to carry.

    C) Fatigue and performance in ultra-endurance exercise, such as military efforts, is determined by (in part) other factors compared to traditional endurance sports. One of the most important aspects is energy balance. The total energy expenditure for a 24-h Adventure Race can be as high as 18-20 000 kcal (Enqvist et al. 2010). One reason for fatigue is the substantial energy deficit. Partly because that the profile of amino acids in blood and muscle change (Borgenvik et al. 2012), muscle damage (Wichardt et al. 2011), hormonal changes (Berg et al 2008), and immunological responses (Wallberg et al. 2011, Marklund et al. 2013). This combined indicates that specific supplementations may be needed. We have recently examined the energy balance in military situations. Two situations were 100 h, 78 km by foot in summer alpine terrain (6200 kcal/24h), and 187 h of mixed military tasks (5600 kcal/24h). Even though the allotment of rations was sufficient to cover the energy expenditure the actual intake was substantially lower, energy deficit being approximately 50 % and 33 %, respectively. However, we see large individual differences. If possible, energy availability should be individualized so that heavier soldiers and those with heavier tasks have opportunities to get higher energy supply compared to soldiers with lighter tasks and lower weight.

  • 377.
    Mattsson, C. Mikael
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Björn Ekblom's research group.
    Så påverkas hjärtat: Nya avhandlingar: Physiology of Adventure Racing - with emphasis on circulatory response and cardiac fatigue2011In: Svensk IdrottsMedicin, ISSN 1103-7652, Vol. 30, no 4, p. 22-27Article in journal (Other academic)
    Abstract [sv]

    Det övergripande målet med denna avhandling är att redogöra för hur den centrala cirkulationen påverkas av ultra-uthållighetsarbete (multisport/Adventure Racing), samt bidra till kartläggningen av den så kallade "arbetsinducerade hjärtutmattningen".

  • 378.
    Mattsson, C. Mikael
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Björn Ekblom's research group.
    Vad vet vi idag om konditionsträning?2010In: Svensk Idrottsforskning: Organ för Centrum för Idrottsforskning, ISSN 1103-4629, Vol. 19, no 2, p. 10-13Article in journal (Other academic)
    Abstract [sv]

    Finns det några nyheter om konditionsträning? Eller är det samma gamla skåpmat som ompaketeras och tröskas ett nytt varv? Artikeln är ett försök att klargöra en del grundläggande bitar, samt att plocka fram några nya aspekter på området.

  • 379.
    Mattsson, C. Mikael
    et al.
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Åstrand Laboratory of Work Physiology, Björn Ekblom's and Mats Börjesson's research group.
    Berglund, Bo
    Department of Medicine, Internal Medicine Unit, Karolinska Institutet, Karolinska University Hospital Solna, Sweden.
    Ekblom, Björn
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Åstrand Laboratory of Work Physiology, Björn Ekblom's and Mats Börjesson's research group.
    Extreme values of NT-proBNP after ultra-endurance exercise in healthy athletes – Related to impaired exercise performance?2011Article in journal (Refereed)
  • 380.
    Mattsson, C. Mikael
    et al.
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences.
    Björkman, Frida
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Björn Ekblom's research group.
    Edin, Fredrik
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Björn Ekblom's research group.
    Larsen, Filip
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Björn Ekblom's research group.
    Ekblom, Björn
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Björn Ekblom's research group.
    Regular moist snuff dipping does not affect endurance exercise performance2013Conference paper (Refereed)
    Abstract [en]

    Physiological and medical effects of snuff have previously been obtained either in cross-sectional studies or after snuff administration to non-tobacco users, but the effects of snuff cessation (SC) after several years of daily use on individual level are unknown. 24 participants with >2 years of daily snuff-use were tested before and after >6 weeks SC (SCG), together with a control group (CO) of 11 snuff users who kept their normal habits. Resting heart rate (HR) was significantly lower in SCG after SC. Body mass in SCG group increased by 1.4 ± 1.7 kg and blood pressure (BP) were reduced, but without significant differences between groups. Total cholesterol increased from 4.12 ± 0.54 (95% CI 3.89–4.35) to 4.46 ± 0.70 (95% CI 4.16–4.75) mM/L in SCG, due to increased LDL, and this change was significantly different from CO. Resting values of HDL, C-reactive protein, and free fatty acids (FFA) remained unchanged in both groups. During a four-stage incremental (from 50 to 80% of VO2max) and a prolonged (60 min at 50% of VO2max) cycling test HR and BP were reduced in SCG, while oxygen uptake (VO2), respiratory exchange ratio, blood lactate (bLa) and blood glucose (bGlu) concentration, and rate of perceived exertion were unchanged. All measurements were unchanged in CO. During the prolonged exercise FFA was reduced but there was no significant difference between groups. During the maximal treadmill running test peak values of VO2, pulmonary ventilation (VE), time to exhaustion and bLa were unchanged in both groups. In conclusion, endurance exercise performance (VO2max and maximal endurance time) does not seem to be affected by prolonged snuff use, while effects on cardiovascular risk factors are contradictory.

  • 381.
    Mattsson, C. Mikael
    et al.
    Swedish School of Sport and Health Sciences, GIH.
    Enqvist, Jonas
    Swedish School of Sport and Health Sciences, GIH.
    Brink-Elfegoun, Thibault
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Björn Ekblom's research group.
    Johansson, Patrik
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Björn Ekblom's research group.
    Bakkman, Linda
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Research group for Mitokondriell funktion och metabolisk kontroll.
    Ekblom, Björn
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Björn Ekblom's research group.
    Unexpected cardiovascular response during ultra-endurance exercise.2008In: 13th Annual Congress of the European College of Sport Science (ECSS), Estoril, Lissabon, Portugal.: Sport Science by the sea, 2008, p. 142-Conference paper (Other academic)
    Abstract [en]

    During prolonged exercise at fixed work rate heart rate (HR) increases slowly with concomitant decrease in stroke volume (SV) in order to maintain cardiac output. Simultaneously, an increased oxygen uptake (VO2) occurs. In this paper we report an unexpected and previously not observed cardiovascular response to ultra-endurance exercise. Nine well-trained male athletes performed 24-h exercise in a controlled laboratory setting, with altering blocks of kayaking, running and cycling. Each block consisted of 110 min of exercise and 10 min of rest. Measurements (HR, VO2 and blood samples) were conducted during cycling at fixed work rate every 6th hour. The average work intensity was approximately 55 % of respective VO2peak. HR was increased at 6 h with 15 beats/min (13 %) compared to pre-exercise (Pre-Ex), but thereafter unexpectedly returned towards initial values. VO2 on the other hand was increased with 0.22 l/min (10 %) at 6 h and 0.37 l/min (17 %) at 12 h compared to Pre-Ex, and thereafter remained stable. This implies an increased oxygen pulse (VO2/HR) with approximately 10 % compared to Pre-Ex at the later half of the exercise. The cardiovascular drift did not progress continuously, but instead changed drastically when duration exceeded 6 hours. The changes in HR and VO2 might have different and complex explanations. HR drift might be explained mainly by central circulatory adaptation (e.g. desensitisation of cardiac adrenergic receptors) whereas drift in VO2 may depend upon peripheral changes (e.g. decreased mitochondrial efficiency). Consequently, using solely HR for determining exercise intensity and energy expenditure becomes invalid during ultra-endurance exercise, if the cardiovascular drift is not measured and taken into account.

     

  • 382.
    Mattsson, C. Mikael
    et al.
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Björn Ekblom's research group.
    Enqvist, Jonas K.
    Inst för kost- och idrottsvetenskap, Göteborgs universitet.
    Stort underskott på energi2011In: Svensk IdrottsMedicin, ISSN 1103-7652, Vol. 30, no 4, p. 12-17Article in journal (Other academic)
    Abstract [sv]

    Det är vanligt att multisportare hamnar i negativ energibalans. Det tycks vara svårt att äta tillräckligt för att täcka det enormt stora energibehovet. Kostrekommendationer för uthållighetsidrottare är heller inte helt gångbara inom multisport.

  • 383.
    Mattsson, C. Mikael
    et al.
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Björn Ekblom's research group.
    Enqvist, Jonas K.
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Björn Ekblom's research group.
    Träning för långdistans: De senaste rönen2007In: Outside, ISSN 1652-4624, no 3, p. 44-48Article in journal (Other academic)
    Abstract [sv]

    Många tidskrifter skriver om optimala metoder för att öka sin prestationsförmåga, gå ner i vikt, eller helt enkelt se snyggare ut. Följande artikel är ett försök att ge dig verktygen för att själv kunna optimera din träning. 

  • 384.
    Mattsson, C. Mikael
    et al.
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Björn Ekblom's research group.
    Enqvist, Jonas K
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Björn Ekblom's research group.
    Berglund, Bo
    Karolinska Institutet.
    Ekblom, Björn
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Björn Ekblom's research group.
    Extreme values of cardiac peptide NT-proBNP after ultra-endurance exercise in healthy athletes2010In: Book of Abstracts of the 15th Annual Congress of the European College of Sport Science – 23-26 June 2010 Antalya - Turkey.: Sport Science: Where the cultures meet / [ed] Korkusuz, F., Ertan, H., Tsolakidis, E., 2010, p. 35-36Conference paper (Other academic)
    Abstract [en]

    Introduction: In clinical medicine, natriuretic peptides, including N-terminal B-type natriuretic peptide (NT-proBNP), are used to detect increased myocardial wall tension in conditions such as heart failure. Tachycardia, arrhythmias and physical exercise may also increase these peptides. The clinical reference value is <100 ng/l, and in clinical practice values >300 ng/l are a strong indicators of heart failure, and values >5000 ng/l highly significant for mortality within 3 months.

    Methods: We examined the levels of NT-proBNP after ultra-endurance exercise, and also made an attempt to relate NT-proBNP to performance. The subjects (12 males and 3 females) participated in the Adventure Racing World Championship, a 5-6 days non-stop competition open for mixed gender team of four athletes. They were all healthy, well-trained athletes with experience from several years of competitions at international elite level. Blood samples for determination of NT-proBNP were drawn before exercise (Pre-Ex), at the end of the race (End-Ex) and 24 hours after exercise (Post-Ex). Each athlete rated his/her own performance at the end of the race (i.e. the last 12 hours) on a scale from 1 (good, stronger than teammates), 2 (intermediate) and 3 (poor, got towed in, needed help from teammates). In addition, each athlete was also rated according to the same scale by the other three members of his/her team. Thereafter the four rates were pooled. Note that the rating is in relation to the team rather than the result of the competition.

    Results: The average exercise duration was approx. 150 hours, and the calculated average work intensity was 40 % (in percent of respective VO2peak), including time for rest, change of equipment, and food intake. The levels of NT-proBNP increased from 31 ± 14 (10-56) [mean ± SD (min-max)] at Pre-Ex to 487 ± 648 (52-2480) at End-Ex. At Post-Ex the corresponding levels were 224 ± 219 (12-634). At End-Ex seven subjects had NT-proBNP below the reference value. The rated performance for four of them was 1, and the remaining three were rated as 2. Three of the subjects had markedly higher levels than previously reported (>900 ng/l) and they were rated 3, 3 and 2, respectively.

    Discussion: Extreme levels of NT-proBNP, up to 2500 ng/l, are present after ultra-endurance exercise in healthy athletes without any clinical signs or symptoms of heart failure. On the other hand, these extreme values may be an indicator of cardiac fatigue, previously described after endurance exercise. Furthermore, in this study high levels of NT-proBNP seem to be associated with decreased exercise performance.

  • 385.
    Mattsson, C. Mikael
    et al.
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Björn Ekblom's research group.
    Enqvist, Jonas K
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Björn Ekblom's research group.
    Brink-Elfegoun, Thibault
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Björn Ekblom's research group.
    Johansson, Patrik H
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Björn Ekblom's research group.
    Bakkman, Linda
    Swedish School of Sport and Health Sciences, GIH.
    Ekblom, Björn
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Björn Ekblom's research group.
    Reversed drift in heart rate but increased oxygen uptake at fixed work rate during 24 h ultra-endurance exercise.2010In: Scandinavian Journal of Medicine and Science in Sports, ISSN 0905-7188, E-ISSN 1600-0838, Vol. 20, no 2, p. 298-304Article in journal (Refereed)
    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.

  • 386.
    Mattsson, C. Mikael
    et al.
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences.
    Enqvist, Jonas K.
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Björn Ekblom's research group.
    Ekblom, Björn
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Björn Ekblom's research group.
    The adventure racing athlete: a physiological profile2013Conference paper (Refereed)
    Abstract [en]

    Introduction: The aim of this study was anthropometric and physiological characterisation of male and female adventure racing athletes (ARs), and also to compare top and bottom finishers in the Adventure Racing World Championship (ARWC) 2006.

    Methods: The physiological profile was developed from oxygen uptake during submaximal and maximal exercise on treadmill, cycle- and kayakergometers. The characterisation study included 15 male and 9 female ARs. Additional anthropometric measurements were obtained from 128 participants in the ARWC.

    Results: The anthropometrics for male ARs were: [mean (95% confidence interval)] age 33 (32-34) years, height 180 (179-181) cm, body mass (BM) 79.4 (78.1-80.7) kg, body fat 17.1 (16.5-17.7) % of BM. Corresponding values for female ARs were: age 31 (30-32) years, height 165 (163-167) cm, BM 61.6 (59.8-63.4) kg, body fat 24.7 (23.6-25.8) % of BM. The men's peak oxygen uptakes were: running 5.02 (4.82-5.22), cycling 4.99 (4.80-5.18), and kayaking 4.05 (3.84-4.26) L/min. Corresponding values for the women were: running 3.26 (3.02-3.50), cycling 3.27 (3.05-3.47), and kayaking 2.59 (2.34-2.84) L/min. The characterized ARs had fractional utilisation in the order: running > cycling > kayaking (best trained in running), indicating that a shift in training regime in favour of kayak training could result in better overall performance. Top male finishers in the ARWC were taller, heavier, had a higher BMI and a trend towards higher body fat than bottom finishers, while there were no such differences among the women. The ARs display a distinct profile, in both anthropometric and physiological aspects, which differs from the specialist athletes'. The ARs have to balance a wide variety of demands, such as sufficient endogenous storage of fat and high ability to carry, against sustained ability to run and perform other BM related tasks.

  • 387.
    Mattsson, C. Mikael
    et al.
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences.
    Flockhart, Mikael
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Åstrand Laboratory of Work Physiology, Björn Ekblom's research group.
    Söderlund, Karin
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Åstrand Laboratory of Work Physiology.
    Hendo, Gina
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Åstrand Laboratory of Work Physiology.
    Jakobsson, Madeleine
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Åstrand Laboratory of Work Physiology.
    Pontén, Marjan
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Åstrand Laboratory of Work Physiology.
    Ekblom, Björn
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Åstrand Laboratory of Work Physiology, Björn Ekblom's research group.
    Effects of prolonged low intensity exercise with energy deficit (military training operation) on markers of muscle protein turnover.2015Conference paper (Refereed)
    Abstract [en]

    Introduction

    It is well known that ultra-endurance exercise, such as Adventure racing and military operations, often induce substantial energy deficits. This suggests a catabolic state, but the exact effects on protein turnover have not yet been sufficiently investigated. The aim of this study was to examine several markers involved in muscle protein turnover before and after a multi-day physically demanding military training operation.

    Methods

    Seven female (age 21 ± 5 years, weight 71.2 ± 6.6 kg) and seventeen male (age 20 ± 1 years, weight 76.6 ± 6.2 kg) performed a 185 hours military training operation. Energy intake was estimated from food supply and energy expenditure was calculated from continuous heart rate and accelerometer recordings. Muscle biopsies were taken from M Vastus Lateralis before and after the operation.

    Results

    A negative energy balance of 1,500-2,000 kcal/24 hours was estimated. Body weight declined 3.4 (95% CI 3.0-3.8) kg and muscle explosive strength, evaluated from squad and counter movement jumps, was reduced 5 and 6 %, respectively, after the operation with no difference between genders. Muscle glycogen content was reduced from 269 ± 58 to 181 ± 44 mmol/kg dry muscle (p<0.05) with no difference between genders. Muscle content of mTOR and p70 as well as MAFbx were unchanged while the protein content of MuRF-1 was significantly down regulated in both genders.

    Discussion

    The study indicated that prolonged low intensity exercise with substantial energy deficit reduces muscle function and muscle glycogen content. Proteins for muscle synthesis mTOR and p70 were unchanged while the down regulation of MuRF-1 indicates a protection against muscle break down during the energy deficit situation, preserving the muscle mass.

  • 388.
    Mattsson, C. Mikael
    et al.
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Åstrand Laboratory of Work Physiology, Björn Ekblom's research group.
    Jansson, Eva
    Karolinska institutet.
    Hagströmer, Maria
    Karolinska institutet.
    Fysisk aktivitet - begrepp och definitioner2016In: FYSS 2017: fysisk aktivitet i sjukdomsprevention och sjukdomsbehandling, Läkartidningen förlag , 2016, p. 21-34Chapter in book (Other academic)
    Abstract [sv]

    Sammanfattning

    Fysisk aktivitet är ett komplext beteende och definieras, rent fysiologiskt, som all kroppsrörelse som ökar energiförbrukningen utöver viloförbrukning.

    Aerob fysisk aktivitet är den vanligaste formen och kan utföras på olika intensiteter, från låg till mycket hög. Aerob fysisk aktivitet som utförs i strukturerad form med syfte att öka eller bibehålla konditionen kan benämnas konditionsträning.

    Muskelstärkande fysisk aktivitet är den form av fysisk aktivitet som belastar och ställer krav på muskelstyrkan. Muskelstärkande fysisk aktivitet som utförs i strukturerad form kan benämnas styrketräning.

    Grundläggande principer för kroppens svar på träning, som ”overload”, progression, reversibilitet, specificitet och individuella skillnader presenteras.

  • 389.
    Mattsson, C. Mikael
    et al.
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences.
    Larsen, Filip
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Åstrand Laboratory of Work Physiology, Björn Ekblom's and Mats Börjesson's research group.
    Kondition och uthållighet: För träning, tävling och hälsa2013Book (Other (popular science, discussion, etc.))
    Abstract [sv]

    Vilken intervallform är den mest effektiva i syfte att förbättra konditionen? Är det viktigt att ett träningsupplägg styrs av individualisering? Vilka positiva hälsoeffekter medför en förbättrad kondition? Och vad händer i framtiden – kommer drömgränsen under två timmar på maraton, att sprängas?

    En sammanställning och tolkning av den kunskap vi i nuläget har om fysiologi och träningslära.

    Boken Kondition och uthållighet är en sammanställning och tolkning av den kunskap vi i nuläget har om fysiologi och träningslära. Den beskriver en mängd faktorer och situationer kopplade till träning, prestation, utveckling och hälsa. Den vägleder dig som planerar och genomför träningen - aktiv eller tränare – att välja rätt träningsupplägg med hänsyn till träningsgrad och ambitionsnivå.

    Hälsoeffekter och ofattbara prestationer

    Att träna sin kondition medför en lång rad positiva hälsoeffekter såsom ökad livslängd, förbättrad livskvalitet och minskad risk för en mängd sjukdomar. Vid ökad träningsdos genomgår kroppen en rad förändringar för att anpassa sig till de krav som belastningen kräver. Kroppen är lyckligtvis enormt anpassningsbar och får den bara tillräckligt mycket träning kan den lära sig att tåla stora påfrestningar. Detta bidrar till att idrottare som specialiserar sig, och tränar mycket under lång tid, kan uppnå häpnadsväckande prestationer. Ju sämre kondition och uthållighet du har, desto mindre krävs för att du ska förbättra dig. Ju bättre kondition och uthållighet du har, desto hårdare belastning krävs för att du ska förbättra dig ytterligare.

    Pulsträning

    Ett sätt att mäta träningsbelastning är att använda puls och pulsklocka. Författarna, som även har skrivit träningshäftet Pulsträning (SISU Idrottsböcker 2011), förordar en indelning med sex intensitetszoner som baseras på beräkningar av individuella värden på vilo-, tröskel- och maxpuls. Beroende på hur vältränad man är kommer de olika zonerna att hamna mellan olika pulsnivåer. I den här boken beskrivs vad som tränas i de olika zonerna och varför man utför denna träning, samt hur man ska fördela träningsmängden mellan de olika zonerna.

    Intervallträning och individualisering

    Intervallträning innebär att man delar upp ett träningspass i mindre bitar med viloperioder i mellan, vilket möjliggör att hårda träningspass kan genomföras med en större mängd arbete på hög intensitet. Forskning tyder på att högintensiv intervallträning behövs för att man ska få ut så mycket som möjligt av sin konditionsträning. Vid intervallträning är det extra tydligt att man för bästa effekt bör utgå från sin egen förmåga; att man strävar efter en relativ belastning och upplevelse av trötthet, under och efter intervallpassen.

    Bokens upplägg

    Bokens första del går igenom grunderna i fysiologi och den andra delen handlar om vad som händer och vad man behöver tänka på vid planering, utförande och utvärdering av träning och tävling i konditions- och uthållighetsidrotter. Kondition och uthållighet tar också upp områden som återhämtning, skador, olika riskfaktorer och näringslära, vilka har en direkt betydelse för konditionsträning, oavsett om det handlar om att vinna OS eller träning för hälsa och ett långt aktivt liv.

  • 390.
    Mattsson, C. Mikael
    et al.
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Åstrand Laboratory of Work Physiology, Björn Ekblom's and Mats Börjesson's research group.
    Larsen, Filip
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Åstrand Laboratory of Work Physiology, Björn Ekblom's and Mats Börjesson's research group.
    Pulsträning2011Book (Other (popular science, discussion, etc.))
    Abstract [sv]

    Att träna pulsbaserat skapar perfekta förutsättningarna för en positiv utveckling av din kondition eftersom du tränar utifrån din egen förmåga. Pulsen hjälper dig att träna på rätt nivå på de enskilda träningspassen och kan användas vid all form av konditionsträning. I häftet Pulsträning lär du dig grunderna för att träna med puls och hur du genom att använda olika belastningar kan uppnå olika effekter av din träning.  Du får också förslag på olika tester som både hjälper dig att träna effektivare och skapar motivation.

  • 391.
    Mattsson, C. Mikael
    et al.
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Åstrand Laboratory of Work Physiology.
    Larsen, Filip
    Karolinska insitutet.
    Holmberg, Hans Christer
    Mittuniversitetet.
    Den nödvändiga distansträningen2014In: Svensk Idrottsforskning: Organ för Centrum för Idrottsforskning, ISSN 1103-4629, Vol. 23, no 3, p. 8-13Article in journal (Other academic)
    Abstract [sv]

    Korta och intensiva intervallpass är ett trendigt sätt att förbättra sin kondition. Men för att bli en bra löpare, längdåkare eller cyklist måste man träna många långa pass i ett lägre tempo. Forskning har visat att högintensiv intervallträning är tidseffektiv och ger bra effekt på många parametrar som är viktiga för konditionsidrottare. Tanken att ersätta nötandet i spåret med kort och snabb träning kan därför låta lockande. Men fullt så enkelt är det inte. Idrottsfysiologerna Mikael Mattsson, Filip Larsen och H-C Holmberg har studerat den forskning som finns om distansträning. Den visar att det inte går att komma runt den lågintensiva träningen om man vill bli en riktigt bra löpare, orienterare, längdskidåkare eller cyklist. På maraton finns till exempel ett nästan linjärt förhållande mellan träningsmängd och prestation. Ju fler mil löparen tränar i veckan desto bättre blir tiden. Kanske räcker det med att studera hur eliten tränar för att förstå distansträningens betydelse. Visserligen är den intensiva intervallträningen viktig även för dem, särskilt inför viktiga tävlingar. Men upp till 90 procent av den totala träningstiden eller minst 3-4 timmar per dag ägnar de åt mer lågintensiva pass.

  • 392.
    Mattsson, C. Mikael
    et al.
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Björn Ekblom's research group.
    Lind, Britta
    KTH, Skolan för teknik och hälsa.
    Enqvist, Jonas K.
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Björn Ekblom's research group.
    Mårtensson, Mattias
    KTH, Skolan för teknik och hälsa.
    Ekblom, Björn
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Björn Ekblom's research group.
    Brodin, Lars-Åke
    KTH, Skolan för teknik och hälsa.
    No evidence of cardiac fatigue in tissue velocity curves at rest after 6 days of ultra-endurance exercise2010In: European Heart Journal (2010) 31 (Abstract Supplement), 304-305, Oxford Journals , 2010, Vol. 31, no Abstract supplement, p. 304-305Conference paper (Refereed)
    Abstract [en]

    Purpose: The aim of this study was to investigate if extreme workload would induce signs of cardiac fatigue similar to that in skeletal muscle, e.g. decreased velocity of contraction.

    Methods: The subjects were 12 men and 3 women who participated in the Adventure Racing World Championship, a 5-7 days non-stop competition open for mixed gender teams of four. All subjects were healthy, well-trained ultra-endurance athletes with experince from several years of training and competition at international elite level. Measurements of the heart's contraction velocities were conducted using tissue Doppler imaging (VIVID7) in a resting situation at baseline, immediately after the race, and after 24 hours of recovery.

    Results: Characteristics for the subjects were at baseline (mean ± SD, for men and women): age 30±3 and 27±4; interventricular septal thickness 10.5±0.7 and 8.0±0.0 mm; left ventricular end-diastolic diameter 54.4±3.4 and 45.0±3.0 mm; posterior wall thickness 10.4±0.9 and 8.0±1.0 mm; early to late diastolic filling velocity (E/A) 2.3±0.6 and 2.2±0.2. Exercise duration was approx. 150 hours, and the calculated average work intensity was 40% of respective VO2peak, including time for rest, change of equipment, and food intake. Values of contraction velocities are presented in the table.

    Conclusions: All athletes had normally sized hearts. Based on contraction velocities we found no evidence of cardiac fatigue after ultra-endurance exercise. A difference compared to studies that found cardiac fatigue in other sports (e.g. marathon, triathlon) is that even though our population exercised for an extreme duration the average intensity was low. This might point towards that exercise intensity, not duration, is the primary source for cardiac fatigue.

  • 393.
    Mattsson, C. Mikael
    et al.
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Åstrand Laboratory of Work Physiology, Björn Ekblom's and Mats Börjesson's research group.
    Lind, Britta
    School of Technology and Health, Royal Institute of Technology (KTH).
    Enqvist, Jonas K.
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Åstrand Laboratory of Work Physiology, Björn Ekblom's and Mats Börjesson's research group.
    Mårtensson, Mattias
    School of Technology and Health, Royal Institute of Technology (KTH).
    Ekblom, Björn
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Åstrand Laboratory of Work Physiology, Björn Ekblom's and Mats Börjesson's research group.
    Brodin, Lars-Åke
    School of Technology and Health, Royal Institute of Technology (KTH).
    No evidence of cardiac fatigue in tissue velocity curves at rest after 6 days of ultra-endurance exercise.2011Article in journal (Refereed)
  • 394.
    Mattsson, C. Mikael
    et al.
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Björn Ekblom's research group.
    Ståhlberg, Marcus
    Institutionen för Medicin, Enheten för kardiologi, Karolinska Universitetssjukhuset.
    Larsen, Filip
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Björn Ekblom's research group.
    Braunschweig, Frieder
    Institutionen för Medicin, Enheten för kardiologi, Karolinska Universitetssjukhuset.
    Ekblom, Björn
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Björn Ekblom's research group.
    Late cardiovascular drift observable during ultra endurance exercise.2011In: Medicine & Science in Sports & Exercise, ISSN 0195-9131, E-ISSN 1530-0315, Vol. 43, no 7, p. 1162-1168Article in journal (Refereed)
    Abstract [en]

    Introduction: The present study investigates the adaptation of the central circulation to ultraenduranceexercise, including the relative contributions of changes in stroke volume (SV) andarterio-venous oxygen difference (a-v O2 diff) to the increased oxygen pulse (VO2/HR).Methods: We evaluated subjects undergoing 12h of mixed exercise at controlled intensity(n=8) and a 53h Adventure race (n=20). Heart rate (HR), oxygen uptake (VO2), and cardiacoutput determined using non-invasive gas rebreathing (CORB) were measured during cyclingat fixed work rate after 0, 4, 8, 12 hours, and 0, 20, and 53 hours of continuous exercise in the12 and 53 h protocol, respectively.Results and Conclusion: The central circulation changed in several steps in response to ultraenduranceexercise. Compared to initial levels, VO2 was increased at every time-point measured.The increase was attributed to peripheral adaptations, confirmed by a close correlation betweenchange in VO2 and change in a-v O2 diff. The first step of the circulatory response was typical ofnormal (early) cardiovascular drift, with increased HR and concomitantly decreased SV andVO2/HR, occurring over the first 4-6 h. The second step, which continued until approximately 12h, included reversed HR-drift, with normalization of SV and VO2/HR. When exercise continueduntil 50 h late cardiovascular drift was noted, characterized by increased VO2/HR, (indicatingmore efficient energy distribution), decreased peripheral resistance, increased stroke volume, anddecreased work of the heart. Since cardiac output was maintained at all time points we interpretthe changes as physiologically appropriate adaptations to ultra-endurance exercise.

  • 395.
    Mattsson, C. Mikael
    et al.
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Björn Ekblom's research group.
    Wichardt, Emma
    Idrottsmedicin, Umeå universitet.
    NSAID inom multisport2011In: Svensk IdrottsMedicin, ISSN 1103-7652, Vol. 30, no 4, p. 18-21Article in journal (Other academic)
    Abstract [sv]

    Användning av NSAID är mycket vanligt bland deltagare i längre multisporttävlingar. Ofta i tron att NSAID påskyndar återhämtningen, trots att kunskapen om dess påverkan vid idrott är begränsad. Det är till och med möjligt att NSAID har motsatt effekt och istället påverkar muskelåterhämtning och -uppbyggnad negativt.

  • 396.
    McGawley, Kerry
    et al.
    Mid Sweden University, Östersund.
    Juudas, Elisabeth
    Mid Sweden University, Östersund.
    Kazior, Zuzanna
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Åstrand Laboratory of Work Physiology. Mid Sweden University, Östersund.
    Ström, Kristoffer
    Mid Sweden University, Östersund, Lund University.
    Blomstrand, Eva
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Åstrand Laboratory of Work Physiology.
    Hansson, Ola
    Lund University.
    Holmberg, Hans-Christer
    Mid Sweden University, Östersund.
    No Additional Benefits of Block- Over Evenly-Distributed High-Intensity Interval Training within a Polarized Microcycle2017In: Frontiers in Physiology, ISSN 1664-042X, E-ISSN 1664-042X, Vol. 8, article id 413Article in journal (Refereed)
    Abstract [en]

    The current study aimed to investigate the responses to block- versus evenly-distributed high-intensity interval training (HIT) within a polarized microcycle. Twenty well-trained junior cross-country skiers (10 males, age 17.6±1.5 and 10 females, age 17.3±1.5) completed two, 3-week periods of training (EVEN and BLOCK) in a randomized, crossover-design study. In EVEN, 3 HIT sessions (5x4-min of diagonal-stride roller-skiing) were completed at a maximal sustainable intensity each week while low-intensity training (LIT) was distributed evenly around the HIT. In BLOCK, the same 9 HIT sessions were completed in the second week while only LIT was completed in the first and third weeks. Heart rate (HR), session ratings of perceived exertion (sRPE) and perceived recovery (pREC) were recorded for all HIT and LIT sessions, while distance covered was recorded for each HIT interval. The recovery-stress questionnaire for athletes (RESTQ-Sport) was completed weekly. Before and after EVEN and BLOCK, resting saliva and muscle samples were collected and an incremental test and 600-m time-trial (TT) were completed. Pre- to post-testing revealed no significant differences between EVEN and BLOCK for changes in resting salivary cortisol, testosterone or IgA, or for changes in muscle capillary density, fiber area, fiber composition, enzyme activity (CS, HAD and PFK) or the protein content of VEGF or PGC-1α. Neither were any differences observed in the changes in skiing economy, VO2max or 600-m time-trial performance between interventions. These findings were coupled with no significant differences between EVEN and BLOCK for distance covered during HIT, summated HR zone scores, total sRPE training load, overall pREC or overall recovery-stress state. However, 600-m TT performance improved from pre- to post-training, irrespective of intervention (P=0.003), and a number of hormonal and muscle biopsy markers were also significantly altered post-training (P<0.05). The current study shows that well-trained junior cross-country skiers are able to complete 9 HIT sessions within one week without compromising total work done and without experiencing greater stress or reduced recovery over a 3-week polarized microcycle. However, the findings do not support block-distributed HIT as a superior method to a more even distribution of HIT in terms of enhancing physiological or performance adaptions.

  • 397. Metaxas, Thomas I
    et al.
    Mandroukas, Athanasios
    Vamvakoudis, Efstratios
    Kotoglou, Kostas
    Ekblom, Björn
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Åstrand Laboratory of Work Physiology, Björn Ekblom's and Mats Börjesson's research group.
    Mandroukas, Konstantinos
    Muscle fiber characteristics, satellite cells and soccer performance in young athletes.2014In: Journal of Sports Science and Medicine (JSSM), ISSN 1303-2968, Vol. 13, no 3, p. 493-501Article in journal (Refereed)
    Abstract [en]

    This study is aimed to examine the muscle fiber type, composition and satellite cells in young male soccer players and to correlate them to cardiorespiratory indices and muscle strength. The participants formed three Groups: Group A (n = 13), 11.2 ± 0.4yrs, Group B (n=10), 13.1 ± 0.5yrs and Group C (n = 9), 15.2 ± 0.6yrs. Muscle biopsies were obtained from the vastus lateralis. Peak torque values of the quadriceps and hamstrings were recorded and VO2max was measured on the treadmill. Group C had lower type I percentage distribution compared to A by 21.3% (p < 0.01), while the type IIA relative percentage was higher by 18.1% and 18.4% than in Groups A and B (p < 0.05). Groups B and C had higher cross-sectional area (CSA) values in all fiber types than in Group A (0.05 < p < 0.001). The number of satellite cells did not differ between the groups. Groups B and C had higher peak torque at all angular velocities and absolute VO2max in terms of ml·min(-1) than Group A (0.05 < p < 0.001). It is concluded that the increased percentage of type IIA muscle fibers noticed in Group C in comparison to the Groups A and B should be mainly attributed to the different workload exercise and training programs. The alteration of myosin heavy chain (MHC) isoforms composition even in children is an important mechanism for skeletal muscle characteristics. Finally, CSA, isokinetic muscle strength and VO2max values seems to be expressed according to age. Key PointsFifteen years old soccer players have higher IIA percentage distribution than the younger players by approximately 18%.The age and the training status play a crucial role in muscle fibers co-expression.Specific training in young athletes seems to alter significantly the muscular metabolic profile.

  • 398.
    Metaxas, Thomas
    et al.
    Aristotle University of Thessaloniki, Greece.
    Mandroukas, Athanasios
    Charles University, Prague, Czech Republic.
    Michailidis, Yiannis
    Aristotle University of Thessaloniki, Greece.
    Koutlianos, Nikolaos
    Aristotle University of Thessaloniki, Greece.
    Christoulas, Kosmas
    Aristotle University of Thessaloniki, Greece.
    Ekblom, Björn
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Åstrand Laboratory of Work Physiology, Björn Ekblom's research group.
    Correlation of Fiber-Type Composition and Sprint Performance in Youth Soccer Players.2019In: Journal of Strength and Conditioning Research, ISSN 1064-8011, E-ISSN 1533-4287, Vol. 33, no 10, p. 2629-1634Article in journal (Refereed)
    Abstract [en]

    The aim of this study was to examine the correlation between muscle fiber type and sprint performance in elite young soccer players of different age groups of the same team. Twenty-eight young players participated in this study (group U15, n = 8; group U13, n = 9; and group U11, n = 11). Anthropometric assessments, acceleration (10 m), and Bangsbo modified sprint test (30 m) were performed. Muscle biopsies were obtained from the vastus lateralis, and after that, fiber-type composition was determined by immunohistochemistry. No significant correlations were found between the sprint test and muscle fiber distribution for the groups U13 and U11 (p > 0.05). Also, no correlations were found between cross-sectional areas in the types of fibers with the sprint test in all groups (p > 0.05). A positive correlation was found between type I fibers and the performance in the acceleration test (10 m) (r = 0.77, p < 0.05) was found only in group U15 and a negative correlation between type IIA fibers and the performance in the acceleration test (10 m) (r = -0.89, p < 0.05). The correlations were observed only in group U15, which may indicate that the duration and the intensity of the soccer systematic training can affect the plasticity of the muscle fibers. Specific soccer training in youth is one of the factors that can affect fiber-type plasticity. The specific training programs and status of U15 are more intensive, and the exercises are oriented more to improve physical fitness.

  • 399.
    Mijwel, S.
    et al.
    Karolinska Institutet.
    Cardinale, Daniele A.
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Åstrand Laboratory of Work Physiology.
    Ekblom Bak, Elin
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Åstrand Laboratory of Work Physiology.
    Sundberg, C. J.
    Karolinska Institutet.
    Wengstrom, Y.
    Karolinska Institutet.
    Rundqvist, H.
    Karolinska Institutet.
    Validation of two submaximal exercise tests in breast cancer patients undergoing chemotherapy treatment2015In: European Journal of Cancer (ISSN 0959-8049), 2015, Vol. 51, p. S300-S301Conference paper (Other academic)
  • 400.
    Mijwel, Sara
    et al.
    Karolinska Institutet, Stockholm, Sweden..
    Backman, Malin
    Karolinska Institutet, Stockholm, Sweden..
    Bolam, Kate A.
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Åstrand Laboratory of Work Physiology.
    Sundberg, Carl Johan
    Karolinska Institutet, Stockholm, Sweden..
    Norrbom, Jessica
    Karolinska Institutet, Stockholm, Sweden..
    Bergh, Jonas
    Karolinska Institutet, Stockholm, Sweden..
    Wengstrom, Yvonne
    Karolinska Institutet, Stockholm, Sweden..
    Rundqvist, Helene
    Karolinska Institutet, Stockholm, Sweden..
    Concurrent Aerobic and Resistance Training Prevents Physical Fatigue in Patients with Breast Cancer during Chemotherapy2017In: Medicine & Science in Sports & Exercise. 49(5S):335, MAY 2017, 2017, Vol. 49, no 5, p. 335-335Conference paper (Refereed)
567891011 351 - 400 of 664
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