Gymnastik- och idrottshögskolan, GIH

Introduction: A well-functioning anti-doping system relies on being perceived by athletes as effective, fair, and practically feasible to implement. While research has highlighted the views of Olympic athletes on anti-doping over the past decade, the experiences and perceptions of Para athletes have not been extensively explored. The purpose of this study was to examine Swedish elite Para athletes' experiences and perceptions of the policy and practice of the anti-doping system.

Methods: A quantitative cross-sectional approach was used, with a web survey elaborated from a survey with Olympic athletes adjusted for Para athletes with physical, visual, and intellectual impairments. The sample consisted of 66 active Para athletes competing at national or international level (response rate 71%). Data were analyzed using descriptive statistics and differences between subgroups were examined Fisher's exact test. Thematic analysis was employed to analyze open-ended questions.

Results: Most of the respondents expressed a positive outlook on the anti-doping system, advocating for comprehensive efforts. A significant portion (35%) had not received anti-doping education, with those who did reporting increased confidence in avoiding unintentional doping. Despite their elite status, half of the respondents had not undergone doping control. Mistrust regarding the system's effectiveness and fairness was identified, with over half of the participants emphasizing the need for new technical solutions to enhance procedures specifically tailored for Para athletes.

Discussion: The athletes in this study advocate for a Para sports-focused approach in the anti-doping system, emphasizing equal testing opportunities, procedural adjustments for independence and privacy, and increased access to education. The findings illuminate the unique conditions faced by athletes with impairments within the anti-doping system, offering valuable insights for policymaking in the development of anti-doping strategies tailored to Para athletes and their various impairments.

OBJECTIVE: Para-cycling classification aims to generate fair competition by discriminating between levels of activity limitation. This study investigated the relationship between lower limb Manual Muscle Tests (MMT) with ratio-scaled measures of isometric and dynamic strength, and of the ratio-scaled measures with cycling performance.

DESIGN: Fifty-six para-cyclists (44 males, 12 females) with leg impairments performed isometric and dynamic strength tests: leg push and pull, and an all-out 20 s sprint. MMT results were obtained from the classification database (n = 21) and race speeds from time trials (n = 54).

RESULTS: Regression analyses showed significant associations of MMT with isometric push (R2 = .49), dynamic push (R2 = .35), and dynamic pull (R2 = .28). Isometric strength was significantly correlated with dynamic push (ρ = .63) and pull (ρ = .54). The isometric and dynamic tests were significantly associated with sprint power and race speed (R2 = .16-.50).

CONCLUSION: The modified MMT and ratio-scaled measures were significantly associated. The significant relation of isometric and dynamic strength with sprint power and race speed maps the impact of lower limb impairments on para-cycling performance. MMT and the isometric and dynamic measures show potential for use in para-cycling classification.

In para-kayak, athletes with unilateral above knee amputation (AK) and athletes with below knee amputation (BK) compete in the same class. This has been questioned since previous research have shown that the legs are important for paddling performance. The purpose was therefore to examine differences in kinematic and kinetic performance variables between AK and BK para-kayak athletes and the amputated (A) and non-amputated (NA) sides. Eleven AK and six BK athletes on international level participated. 3D kinematic and kinetic data were collected for the body, seat, footrest and paddle during kayak ergometer paddling. There were no significant differences between the groups in main performance variables such as power output or paddle force. Differences between the groups were only seen in the hip joint in flexion range of motion, flexion and extension angular velocity and flexion moment where BK demonstrated larger values. The NA side demonstrated greater values compared to the A side in posterior force at the seat and in hip flexion moment. As there were no significant differences between the groups in the majority of the examined key performance variables, the results suggest that athletes with unilateral AK and BK amputation may be able to compete in the same class.

OBJECTIVES: Whilst cycling performance has been studied extensively, very little is known about the performance of para-cyclists. This study assessed the relation between sprint power and road time trial performance in elite para-cyclists, and whether this relation differed based on impairment type and type of bike used.

DESIGN: Cross-sectional.

METHODS: During international para-cycling events, 168 athletes (88 bicycles, 17 tricycles, 56 recumbent handbikes and 7 kneeling handbikes) performed 20-s sport-specific sprint tests (mean power output (POmean) W), and their road time trial performance (average speed (km/h)) was taken from the official results. Multilevel regression models to assess the relation of sprint with time trial performance were composed for i. leg-cyclists: bicycle and tricycle and ii. arm-cyclists: recumbent- and kneeling handbike, adjusted for identified confounders. Furthermore, impairment type (categorized as i) muscle power/range of motion, ii) limb deficiency/leg length difference, and iii) coordination) and bike type were tested as effect modifiers.

RESULTS: POmean ranged from 303 ± 12 W for recumbent handcyclists to 482 ± 156 W for bicyclists. POmean was significantly related to time trial performance, for both leg-cyclists (β = 0.010, SE = 0.003, p < 0.01) and arm-cyclists (β = 0.029; SE = 0.005, p < 0.01), and impairment type and bike type were not found to be effect modifiers.

CONCLUSIONS: Sprint power was related to road time trial performance in all para-cyclists, with no differences found in this relation based on impairment type nor bike type. For those competing on a bicycle, tricycle, recumbent- or kneeling handbike, sprint tests might therefore be useful to predict or monitor time trial performance.

Purpose: The para-cycling classification system, consisting of five classes (C1-C5) for bicycling (C5 athletes having least impairments), is mostly based on expert-opinion rather than scientific evidence. The aim of this study was to determine the differences in race performance between para-cycling classes. Methods: From official results of the men's 1 km time trials for classes C1-C5 of seven Union Cycliste Internationale World Championships and Paralympics, median race speed of the five fastest athletes in each class was calculated (n = 175). Para-cycling results were expressed as a percentage of able-bodied performance using race results from the same years (n = 35). To assess differences between consecutive classes, Kruskal-Wallis tests with Mann-Whitney U post hoc tests were performed, correcting for multiple testing (p < 0.013). Results: Para-cyclists in C1 reached 75% (median ± interquartile range = 44.8 ± 4.2 km/h) and in C5 90% (53.5 ± 2.9 km/h) of able-bodied race speed (59.4 ± 0.9 km/h). Median race speed between consecutive classes was significantly different (χ² = 142.6, p < 0.01), except for C4 (52.1 ± 2.8 km/h) and C5 (U = 447.0, p = 0.05). Conclusion: Current para-cycling classification does not clearly differentiate between classes with least impairments.IMPLICATIONS FOR REHABILITATIONThe current classification system is not evidence-based and does not clearly differentiate between relevant groups of para-cyclists.An evidence-based para-cycling classification system is essential for a fair and equitable competition.Fair competition will make it more interesting and increase participation.Para-cycling can inspire everyone with and even those without disabilities to be physically active.

The purpose of this study was to investigate effects of common modifications of trunk curl-up exercise on the involvement of the abdominal muscles, particularly the deepest muscle layer, transversus abdominis (TrA). Ten healthy females performed five different variations of the trunk curl-up at a standardized speed, varying the exercise by assuming three different arm positions and applying left and right twist. Indwelling fine-wire electromyography (EMG) electrodes were used to record from TrA, obliquus internus (OI), obliquus externus (OE) and rectus abdominis (RA) unilaterally on the right side. Increasing the load by changing the arm position during a straight trunk curl-up increased the EMG of all abdominal muscles. OI and TrA showed higher activation during right twist compared to left twist whereas OE displayed the opposite pattern. RA did not show any change in activation level between twisting directions. The apparent load dependency on the activation level of all muscles and the twisting direction dependency of all muscles except RA are in keeping with the fiber orientation of the muscles. Notably, also TrA, with a less obvious mechanical role with regards to fiber orientation, increased activation with load during the straight trunk curl-up. However, the highest activation level of TrA during the trunk curl-up was only 40 % of a maximum contraction, thus it might not be the most suitable strength training exercise for this muscle.

The purpose of this study was to examine the interrater reliability of a new evidence-based classification system for Para Va'a. Twelve Para Va'a athletes were classified by three classifier teams each consisting of a medical and a technical classifier. Interrater reliability was assessed by calculating intraclass correlation for the overall class allocation and total scores of trunk, leg, and on-water test batteries and by calculating Fleiss's kappa and percentage of total agreement in the individual tests of each test battery. All classifier teams agreed with the overall class allocation of all athletes, and all three test batteries exhibited excellent interrater reliability. At a test level, agreement between classifiers was almost perfect in 14 tests, substantial in four tests, moderate in four tests, and fair in one test. The results suggest that a Para Va'a athlete can expect to be allocated to the same class regardless of which classifier team conducts the classification.

Para Va'a is a new Paralympic sport in which athletes with trunk and/or leg impairment compete over 200 m. The purpose of this study was to examine the impact of impairment on kinematic and kinetic variables during Va'a ergometer paddling. Ten able-bodied and 44 Para Va'a athletes with impairments affecting: trunk and legs (TL), legs bilaterally (BL) or leg unilaterally (UL) participated. Differences in stroke frequency, mean paddling force, and joint angles and correlation of the joint angles with paddling force were examined. Able-bodied demonstrated significantly greater paddling force as well as knee and ankle flexion ranges of movement (ROM) on the top hand paddling side compared to TL, BL and UL. Able-bodied, BL and UL demonstrated greater paddling force and trunk flexion compared to TL, and UL demonstrated larger bottom hand paddling side knee and ankle flexion ROM compared to BL. Significant positive correlations were observed for both male and female athletes between paddling force and all trunk flexion angles and ROM in the trunk and pelvis rotation and bottom hand paddling side hip, knee and ankle flexion. The results of this study are important for creating an evidence-based classification system for Para Va'a.

Trunk, pelvis and leg movement are important for performance in sprint kayaking. Para-kayaking is a new Paralympic sport in which athletes with trunk and/or leg impairment compete in three classification groups. The purpose of this study was to identify how physical impairments impact on performance by examining: differences in three-dimensional joint range of motion (RoM) between 10 (4 females, 6 males) elite able-bodied kayakers and 41 (13 females, 28 males) elite para-kayakersfrom the three classification groups, and which joint angles were correlated with power output during high intensity kayak ergometer paddling. There were significant differences in RoM between the able-bodied kayakers and the three para-kayak groups for the shoulders (flexion, rotation: able-bodied kayakers<para-kayakers), trunk and pelvis (rotation: able-bodied kayakers>para-kayakers) and legs (hip, knee, ankle flexion: able-bodied kayakers>para-kayakers) during paddling. Furthermore, athletes with greater impairment exhibited lower trunk and leg RoM compared to those with less impairment. Significant positive correlations were observed for both males and females between power output and peak shoulder and trunk flexion, trunk and pelvis rotation RoM and hip, knee and ankle flexion RoM. This information is important for understanding how key kinematic and kinetic variables for para-kayaking performance vary between athletes from different classification groups.

Background Spinal cord injury (SCI) results in a complete or partial loss of motor and/or sensory function below the injury level. An SCI causes extensive functional impairment compelling many persons to wheelchair usage. Maintaining an adequate strength and control of trunk and shoulder muscles becomes essential, as the majority of every day tasks will be performed in a sitting position. Moreover, physical exercise is crucial to avoid risks connected with a sedentary life-style. Therefore, it becomes important to find suitable, effective, and attractive physical activities to retain and even improve motor functions achieved during rehabilitation. Ideally, such a training activity should be versatile and have the potential to improve several capacities beneficial to everyday life and thereby increase the independence of persons with SCI. Kayak paddling appears to fulfil several of the criteria for such an activity.

Objectives The overall aims were to see if, and to what extent, a period of training on a modified kayak ergometer could influence functional performance as well as specific qualities, such as, shoulder muscle strength and sitting balance control in a group of post-rehabilitated persons with thoracic SCI.

Methods Ten adult post-rehabilitated persons with thoracic SCI performed 30 sessions of kayak ergometer training for a 10-week period, with progressively increased intensity and balance demand in the medio-lateral direction. Pre- and post-training measurements included performance in functional wheelchair tests, maximal voluntary shoulder muscle strength, and trunk stability in response to support-surface translations.

Results There were significant improvements with training in functional performance, shoulder muscle strength, and the ability to maintain an upright sitting posture in response to balance perturbations in the group of persons with SCI.

Conclusions The improvements in test-performance observed with the kayak ergometer training in the persons with SCI should enhance their capacity to master similar challenges in everyday life, which, in turn, might lead to a greater independence.

The purpose was to examine power output and three-dimensional (3D) kinematic variables in the upper limbs, lower limbs and trunk in elite flat-water kayakers during kayak ergometer paddling. An additional purpose was to analyse possible changes in kinematics with increased intensity and differences between body sides. Six male and four female international level flat-water kayakers participated. Kinematic and kinetic data were collected during three tasks; low (IntL), high (IntH) and maximal (IntM) intensities. No differences were observed in any joint angles between body sides, except for shoulder abduction. Significantly greater range of motion (RoM) values were observed for IntH compared to IntL and for IntM compared to IntL in trunk and pelvis rotation, and in hip, knee and ankle flexion. The mean maximal power output was 610 ± 65 and 359 ± 33 W for the male and female athletes, respectively. The stroke frequencies were significantly different between all intensities (IntL 59.3 ± 6.3; IntH 108.0 ± 6.8; IntM 141.7 ± 18.4 strokes/min). The results showed that after a certain intensity level, the power output must be increased by other factors than increasing the joint angular RoM. This information may assist coaches and athletes to understand the relationship between the movement of the kayaker and the paddling power output.

OBJECTIVE: To use a combination of electrophysiological techniques to determine the extent of preserved muscle activity below the clinically-defined level of motor-complete spinal cord injury.

METHODS: Transcranial magnetic stimulation and vestibular-evoked myogenic potentials were used to investigate whether there was any preserved muscle activity in trunk, hip and leg muscles of 16 individuals with motor-complete spinal cord injury (C4-T12) and 16 able-bodied matched controls.

RESULTS: Most individuals (14/16) with motor-complete spinal cord injury were found to have transcranial magnetic stimulation evoked, and/or voluntary evoked muscle activity in muscles innervated below the clinically classified lesion level. In most cases voluntary muscle activation was accompanied by a present transcranial magnetic stimulation response. Furthermore, motor-evoked potentials to transcranial magnetic stimulation could be observed in muscles that could not be voluntarily activated. Vestibular-evoked myogenic potentials responses were also observed in a small number of subjects, indicating the potential preservation of other descending pathways.

CONCLUSION: These results highlight the importance of using multiple electrophysiological techniques to assist in determining the potential preservation of muscle activity below the clinically-defined level of injury in individuals with a motor-complete spinal cord injury. These techniques may provide clinicians with more accurate information about the state of various motor pathways, and could offer a method to more accurately target rehabilitation.

Objective: To use transcranial magnetic stimulation and electromyography to assess the potential for preserved function in the abdominal muscles in individuals classified with motor-complete spinal cord injury above T6. Subjects: Five individuals with spinal cord injury (C5-T3) and 5 able-bodied individuals. Methods: Transcranial magnetic stimulation was delivered over the abdominal region of primary motor cortex during resting and sub-maximal (or attempted) contractions. Surface electromyography was used to record motor-evoked potentials as well as maximal voluntary (or attempted) contractions in the abdominal muscles and the diaphragm. Results: Responses to transcranial magnetic stimulation in the abdominal muscles occurred in all spinal cord injury subjects. Latencies of muscle response onsets were similar in both groups; however, peak-to-peak amplitudes were smaller in the spinal cord injury group. During maximal voluntary (or attempted) contractions all spinal cord injury subjects were able to elicit electromyography activity above resting levels in more than one abdominal muscle across tasks. Conclusion: Individuals with motor-complete spinal cord injury above T6 were able to activate abdominal muscles in response to transcranial magnetic stimulation and during maximal voluntary (or attempted) contractions. The activation was induced directly through corticospinal pathways, and not indirectly by stretch reflex activations of the diaphragm. Transcranial magnetic stimulation and electromyography measurements provide a useful method to assess motor preservation of abdominal muscles in persons with spinal cord injury.

Study design:Diagnostic study.Objectives:The objective of this study was to compare patterns of electromyography (EMG) recordings of abdominal muscle function in persons with motor-complete spinal cord injury (SCI) above T6 and in able-bodied controls, and to determine whether manual examination or ultrasound measures of muscle activation can be accurate alternatives to EMG.Setting:Research center focused on SCI and University laboratory, Vancouver, Canada.Methods:Thirteen people with SCI (11 with American Spinal Injury Association Impairment Scale (AIS) A and 2 AIS B; C4-T5), and 13 matched able-bodied participants volunteered for the study. Participants completed trunk tasks during manual examination of the abdominal muscles and then performed maximal voluntary isometric contractions, while EMG activity and muscle thickness changes were recorded. The frequency of muscle responses detected by manual examination and ultrasound were compared with detection by EMG (sensitivity and specificity).Results:All individuals with SCI were able to elicit EMG activity above resting levels in at least one abdominal muscle during one task. In general, the activation pattern was task specific, confirming voluntary control of the muscles. Ultrasound, when compared with EMG, showed low sensitivity but was highly specific in its ability to detect preserved abdominal muscle function in persons with SCI. Conversely, manual examination was more sensitive than ultrasound but showed lower specificity.Conclusion:The results from this study confirm preserved voluntary abdominal muscle function in individuals classified with motor-complete SCI above T6 and highlight the need for further research in developing more accurate clinical measures to diagnose the level of trunk muscle preservation in individuals with SCI.Spinal Cord advance online publication, 25 November 2014; doi:10.1038/sc.2014.202.

BACKGROUND AND AIM: Postural control in sitting is essential for people with spinal cord injury (SCI). Studies indicate that impaired postural control is related to decreased propulsion efficiency, respiratory dysfunction and development of pressure sores. Despite this, there is limited knowledge on the best methods to rehabilitate postural control in people with SCI and if and by what mechanism persons with high-thoracic SCI may improve their postural control. Thus, our aims were to 1) determine the efficacy of targeted rehabilitation towards postural control in people with SCI, and 2) investigate the neural mechanisms behind any observed improvements.

METHODS: Persons with SCI completed 30 sessions over 10 weeks of a) seated double poling ergometer (SDP) training (n=13) or b) kayak ergometer (KE) training (n=10). Before and after functional tests were performed and included: sit-and-reach tests, propelling 15m on a level surface and propelling 50m up a 3º incline. Additionally, subjects sat in their wheelchair while support-surface translations were presented (KE) or performed isometric maximal voluntary contractions in a dynamometer during trunk flexion and extension (SDP). To investigate neural mechanisms of postural control improvement, electromyographic (EMG) responses in the ventral postural muscles to maximal voluntary contractions and transcranial magnetic stimulation (TMS) were assessed in 5 individuals with motor complete SCI above T6.

RESULTS: Postural stability was improved after KE and SDP training demonstrated by smaller rotational and linear displacements of the trunk during support surface translations (KE) and improved postural muscle strength (SDP). There were also significant improvements in propelling tasks and in the sit-and-reach tasks, both in the sagittal plane (SDP) as well as in lateral directions (KE). All persons with motor complete SCI above T6 (n=5) were able to elicit task specific EMG activity in the ventral postural muscles during maximal voluntary contractions despite their clinical classification. Motor evoked potentials were also recorded in each individual´s ventral postural muscles in response to TMS, confirming corticospinal pathway preservation.

CONCLUSIONS: Postural control, upright sitting, and functional performance in daily life activities can be improved in people with high-thoracic SCI during regular exercising, such as kayaking and seated double poling ergometer training. The neural mechanism behind the improvement is in part due to partial preservation of the corticospinal pathways to the postural muscles as confirmed by the use EMG and TMS.

Introduction

It is of a significant interest that ergometers used for evaluating elite athletes are valid and reliable. In this study the aim was to investigate how well displayed power output on a widely used kayak ergometer, DS, (Dansprint ApS, DK) related to a validation setup. Previously Gore et al. (2013) described the accuracy of 12 of the same ergometer using a motor driven calibration rig simulating power between 50 up to 450 W. They found that the ergometers underestimated true mean power with 21-23%. The reference rig simulated a 1 dimensional (1D) movement; this study however, is based on 3D analysis, which was hypothesized to better describe real paddling movement’s and allow more precise power calculations.

Methods

Two male national team kayakers took part in the study performing workloads from 70 up to 500 W (+30 W/stage) two times with 3 days between the measurement sessions. They were instructed to target the desired workloads displayed during 35 s bouts. The reference method included a ProReflex optoelectronic system (Qualisys AB, Gothenburg, Sweden) and force transducers (LCM 200, Futek Inc, Ca, US). The force transducers were connected with the rope from ergometer flywheel close to each end of the ergometer paddle to continuously measure force during the bouts of work. The kinematic set-up included eight cameras placed around the ergometer and two reflective markers were attached close to each force transducer.

Results

The reference method used here showed that the validated ergometer underestimated power with 37.7 % over the whole measured range compared to the reference method. The difference was systematic (r2=0.989) and the linear regression model could be applied (DS power = -2.362+0.628*x). When applying a 1D analysis of the collected data, it coincided with the results from Gore et al. (2013).

Discussion

The data suggest that 1. The measurement solution and/or calculation for describing power output in the DS have limitations. 2. The testing rig referred to in the Introduction (Gore et al. 2013) do not fully estimate true power and 3. The reference method used here is suggested to more exactly represent true paddling power as it includes a 3D movement analysis and close to original paddling simulation set-up. Both reference methods (1D and 3D analysis) show linear differences vs. the DS ergometer, giving an option to adjust the displayed power to a true power produced by elite-athletes.

En ryggmärgsskada leder till ett ökat stillasittande. Risken är då stor att drabbas av till exempel hjärt- och kärlsjukdomar. Många får också överbelastningsbesvär från skuldra och arm av ett liv i rullstol. Med högintensiv intervallträning i den nyutvecklade sittstakergometer går det att minska problemen.

Med kajak- och skridskohandboken vill vi dela med oss av våra erfarenheter. Boken kan ses både som en inspirationskälla för nya aktiva och som en handbok för ledare och föreningar som vill starta friluftsverksamhet för personer med funktionsnedsättning.

This study aimed to evaluate biomechanics during seated double-poling exercises in individuals with spinal cord injury (SCI) and to compare these with those of able-bodied persons (AB). 26 participants volunteered for the study; 13 with SCI (injury levels C7-T12), and 13 AB. A seated double-poling ergometer (SDPE) was developed. 3-dimensional kinematics was measured and piezoelectric force sensors were used to register force in both poles for calculation of power during incremental intensities. Significantly lower power outputs, (143.2 ± 51.1 vs. 198.3 ± 74.9 W) and pole forces (137.1 ± 43.1 vs. 238.2 ± 81.2 N) were observed during maximal effort in SCI compared to AB. Sagittal upper trunk range of motion increased with intensity and ranged from 6.1–34.8 ° for SCI, and 6.9–31.3 ° for AB, with larger peak amplitudes in flexion for AB (31.4 ± 12.9 °) compared to SCI (10.0 ± 8.0 °). All subjects with SCI were able to exercise on the SDPE. Upper body kinematics, power and force outputs increased with intensity in both groups, but were in general, lower in SCI. In conclusion, the SDPE could be successfully used at low to high work intensities enabling both endurance and strength training for individuals with SCI

Introduction In wheelchair-dependent individuals with paraplegia, over 80 % would benefit from health-intervention programmes due to increased risks for cardiovascular diseases. One way to reduce the likelihood of secondary complications and/or to enhance physical capacity is to add structured exercise activities to the regular schedule throughout life. A seated double-poling ergometer (SDPE) has been developed and recently evaluated on a group of people with SCI. The results indicated that the SDPE appeared to be a suitable training tool; the shoulder movement was within a range of motion not conducive to musculoskeletal injury and it provided a large range of controllable intensities enabling both endurance and strength training.

Purpose To study if regular interval training on a SDPE can increase physical capacity and hence improve performance towards maximal level with safety in individuals with spinal cord injury.

Methods Thirteen healthy wheelchair users (8 M, 5 F; 47 ± 12 years, 1.75 ± 0.08 m, 67.9 ± 10.2 kg) with SCI levels ranging from T5 to L1, volunteered for the study. Years post injury varied from 3 to 35. All subjects performed 30 sessions of SDPE training during 10 weeks. Each session lasted approximately 55 min, and included a warm-up, interval training (15 s – 3 min work and 15 s – 2 min rest) and a cool-down. The intensity of the intervals was determined to lead up to 70 – 100 % of peak heart rate. Sub-maximal and maximal double-poling ergometer tests were performed before and after this training period. Oxygen uptake was measured using the Douglas Bag system. Three-dimensional kinematics were recorded using an optoelectronic system. 

Results Significant improvements after training were observed in oxygen uptake (23 %), ventilation (21 %) and blood lactate (22 %) during maximal exertion exercises (Table 1). Mean power per stroke and peak pole force increased with 15 % and 24 %, respectively. At sub-maximal level, significantly lower values were observed in ventilation (-13 %) and blood lactate (-25 %).

Conclusion Regular interval training on the seated double-poling ergometer (SDPE) increased oxygen uptake and power out-put and can be recommended for people with paraplegia below T5 level due to SCI. Despite the high intensity training in this study, no overload symptoms were reported. On the contrary, certain types of musculoskeletal and neuropathic pain seem to benefit from training on the SDPE.

Background:  In wheelchair-dependent individuals with paraplegia, over 80 % would benefit from health-intervention programmes due to increased risks for cardiovascular diseases. One way to reduce the likelihood of secondary complications and/or to enhance physical capacity is to add structured exercise activities throughout life.

Objective:  To study the effects of seated double-poling ergometer (SDPE) training on aerobic capacity, upper-body muscle strength, and cross-over effects on functional performance.   

Methods: Thirteen individuals with paraplegia performed 30 sessions of SDPE training during 10 weeks. Before and after the training period a) oxygen uptake was measured using the Douglas Bag system during sub-maximal and maximal double-poling ergometer tests, b) trunk, shoulder and elbow muscle strength measurements were performed during maximal voluntary contractions using an isokinetic dynamometer and c) functional tests in wheelchair were performed included; sit-and-reach test, propelling 15 m on a level surface, propelling 50 m up a 3º incline, and propelling 6 min on a 200 m indoor track. Test-retests were performed for all tests before the training began.

Results: The average intra-class correlation coefficient for test-retest values was 0.91 (SD 0.07). Significant improvements after training were observed in oxygen uptake (22.7 %), ventilation (20.7 %) and blood lactate (22.0 %) during maximal exertion exercises. At sub-maximal level, significantly lower values were observed in ventilation (-12.8 %) and blood lactate (-25.0 %). Maximal isometric trunk muscle strength (17.0 %) and maximal isokinetic shoulder muscle strength (4.4 %) in flexion and extension improved after training. There were significant improvements in sit-and-reach test in forward directions (7.8 %) and in 15 m sprint test (5.2 %).     

Conclusion: Regular interval training on the SPDE was effective for individuals with paraplegia to improve aerobic capacity and upper-body muscle strength. Some cross-over effects on functional performance were also shown. Furthermore, the training did not cause any overload symptoms.

OBJECTIVE: To determine whether regular interval training on a seated double-poling ergometer can increase physical capacity and safely improve performance towards maximal level in individuals with spinal cord injury.

METHODS: A total of 13 subjects with spinal cord injury (injury levels T5-L1) performed 30 sessions of seated double-poling ergometer training over a period of 10 weeks. Sub-maximal and maximal double-poling ergometer tests were performed before (test-retest) and after this training period. Oxygen uptake was measured using the Douglas Bag system. Three-dimensional kinematics were recorded using an optoelectronic system and piezoelectric force sensors were used to register force in both poles.

RESULTS: The mean intra-class correlation coefficient for test-retest values was 0.83 (standard deviation 0.11). After training significant improvements were observed in people with spinal cord injury in oxygen uptake (22.7%), ventilation (20.7%) and blood lactate level (22.0%) during maximal exertion exercises. Mean power per stroke and peak pole force increased by 15.4% and 23.7%, respectively. At sub-maximal level, significantly lower values were observed in ventilation (-12.8%) and blood lactate level (-25.0%).

CONCLUSION: Regular interval training on the seated double-poling ergometer was effective for individuals with spinal cord injury below T5 level in terms of improving aerobic capacity and upper-body power output. The training was safe and did not cause any overload symptoms.

OBJECTIVES: To assess pain relieving effects of an intensive exercise programme on a seated double-poling ergometer in individuals with spinal cord injury (SCI).

SETTING: Stockholm, Sweden.

METHODS: A total of 13 wheelchair-dependent individuals with a thoracic or lumbar SCI were recruited to a 10-week training period (three times weekly) assessing the effects of regular training on upper-body strength, aerobic and mechanical power, and crossover effects on functional performance, as well as cardiovascular risk factors. Eight of the participants reported pain and were included in this exploratory pain protocol and assessed using the International SCI Basic Pain Data set, the Wheelchair Users' Shoulder Pain Index and International SCI Quality of Life Basic Data set.

RESULTS: For those with neuropathic pain, median pain intensity ratings decreased from 5 on a 0-10 numerical rating scale at base-line to 3 at the end of study, and four of seven participants reported an improvement on the Patient Global Impression of Change scale. For those with musculoskeletal pain (n = 5), median pain intensity ratings improved from 4 at baseline to 0 at the end of study. All but one rated no musculoskeletal pain at all at the end of study and number of days with pain per week decreased from 5.5 to 0.7. None of the participants developed pain, because of overuse during the training period and few reported unwanted side effects.

CONCLUSION: Considering its promising effects and safety, an intensive exercise programme can be tried for treating musculoskeletal pain and also neuropathic pain following SCI.

The deepest muscle of the human ventro-lateral abdominal wall, the Transversus Abdominis (TrA), has been ascribed a specific role in spine stabilization, which has motivated special core stability exercises and hollowing instruction to specifically involve this muscle. The purpose here was to evaluate the levels of activation of the TrA and the superficial Rectus Abdominis (RA) muscles during five common stabilization exercises performed in supine, bridging and four-point kneeling positions, with and without instruction to hollow, i.e. to continuously pull the lower part of the abdomen towards the spine. Nine habitually active women participated and muscle activity was recorded bilaterally from TrA and RA with intramuscular fine-wire electrodes introduced under the guidance of ultrasound. Results showed that subjects were able to selectively increase the activation of the TrA, isolated from the RA, with the specific instruction to hollow and that side differences in the amplitude of TrA activity, related to the asymmetry of the exercises, remained even after the instruction to hollow. The exercises investigated caused levels of TrA activation from 4 to 43% of that during maximal effort and can thus be used clinically to grade the load on the TrA when designing programs aiming at training that muscle.

OBJECTIVE: The aim of this study was to assess if, and how, upper body muscles are activated in a person with high thoracic spinal cord injury, clinically classified as complete, during maximal voluntary contractions and in response to balance perturbations. METHODS: Data from one person with spinal cord injury (T3 level) and one able-bodied person were recorded with electromyography from 4 abdominal muscles using indwelling fine-wire electrodes and from erector spinae and 3 upper trunk muscles with surface electrodes. Balance perturbations were carried out as forward or backward support surface translations. RESULTS: The person with spinal cord injury was able to activate all trunk muscles, even those below the injury level, both in voluntary efforts and in reaction to balance perturbations. Trunk movements were qualitatively similar in both participants, but the pattern and timing of muscle responses differed: upper trunk muscle involvement and occurrence of co-activation of ventral and dorsal muscles were more frequent in the person with spinal cord injury. CONCLUSION: These findings prompt further investigation into trunk muscle function in paraplegics, and highlight the importance of including motor tests for trunk muscles in persons with thoracic spinal cord injury, in relation to injury classification, prognosis and rehabilitation.

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

The purpose was to investigate if shoulder muscle strength in post-rehabilitated persons with spinal cord injury (SCI) was affected by kayak ergometer training and to compare shoulder strength in persons with SCI and able-bodied persons. Ten persons with SCI (7 males and 3 females, injury levels T3-T12) performed 60 min kayak ergometer training three times a week for 10 weeks with progressively increased intensity. Maximal voluntary concentric contractions were performed during six shoulder movements: flexion and extension (range of motion 65 degrees ), abduction and adduction (65 degrees ), and external and internal rotation (60 degrees ), with an angular velocity of 30 degrees s(-1). Position specific strength was assessed at three shoulder angles (at the beginning, middle and end of the range of motion) in the respective movements. Test-retests were performed for all measurements before the training and the mean intraclass correlation coefficient was 0.941 (95% CI 0.928-0.954). There was a main effect of kayak ergometer training with increased shoulder muscle strength after training in persons with SCI. The improvements were independent of shoulder movement, and occurred in the beginning and middle positions. A tendency towards lower shoulder muscle strength was observed in the SCI group compared to a matched reference group of able-bodied persons. Thus, it appears that post-rehabilitated persons with SCI have not managed to fully regain/maintain their shoulder muscle strength on a similar level as that of able-bodied persons, and are able to improve their shoulder muscle strength after a period of kayak ergometer training.

Bakgrund

Vid en ryggmärgsskada upphör helt eller delvis överföringen av nervsignaler i ryggmärgen, vilket medför motorisk och sensorisk funktionsnedsättning nedanför skadenivån. I Sverige skadas varje år cirka 150 personer så svårt att det leder till en ryggmärgsskada. Medelåldern vid skadetillfället är cirka 38 år, majoriteten är män (75-80 %) och den vanligaste orsaken är trafikolyckor, följd av fall- och dykolyckor.

Ryggmärgsskador kan medföra tetraplegi eller paraplegi. Tetraplegi innebär att funktionsnedsättningen påverkar arm, bål och ben, medan paraplegi omfattar nedsatt funktion i enbart bål och ben. Skadan kan antingen vara komplett eller inkomplett, d.v.s. ha varierande grad av kvarvarande motorisk och/eller sensorisk funktion nedanför skadeområdet.

Förutom att skadan påverkar känsel och muskelfunktion leder den till en rad andra problem, såsom blås- och tarmrubbning, smärta och spasticitet. Ett av målen med rehabiliteringen efter skada blir därför att minimera effekten av dessa problem. Det övergripande målet är att skapa förutsättningar för att varje individ får möjlighet att bli så självständig som möjlig. För personer som blivit rullstolsbrukare innebär det att optimera funktionen i bål och skuldror, eftersom merparten av vardagliga moment utförs i sittande. Andra viktiga fysiska faktorer är styrka, balans och uthållighet.

Behovet av regelbunden fysisk aktivitet för att bibehålla och/eller förbättra funktioner uppnådda under rehabiliteringsperioden kvarstår hela livet. Genom att utveckla effektiva och attraktiva träningsmetoder kan utövandet av fysisk aktivitet stimuleras. Denna träning bör, förutom att förbättra nämnda prestationsvariabler, också vara skonsam mot axlar och armar, då upprepad ensidig belastning vid exempelvis förflyttningar och rullstolskörning har visat sig leda till ökad förekomst av skulderbesvär hos personer med kronisk ryggmärgsskada.

Kajakpaddling bör vara en lämplig aktivitet för att möta ovanstående krav. De specifika rörelserna som man utför vid kajakpaddling påverkar en stor del av överkroppens muskulatur. Dessutom ställer paddlingen krav på balans, styrka och uthållighet. Kajakpaddling har också visat sig lämplig för personer med ryggmärgsskada och den kan utövas på liknande villkor som för icke-skadade personer.

Paddling i kajakergometer är ett alternativ till paddling på öppet vatten och gör träningen oberoende av utomhusklimatet (dock missas naturupplevelsen). Träning i kajakergometer har visat sig ställa liknade fysiologiska krav som paddling på öppet vatten. En uppenbar skillnad är dock att ergometern, till skillnad från kajaken, vilar på ett stabilt underlag. En del i projektet var därför att utveckla en justerbar balansmodul till ergometern, vilket ger möjlighet att reglera och kontrollera tröghetsmomentet och därmed balanskravet i sidled under paddlingen.

Syfte

Det övergripande syftet med avhandlingsarbetet var att utvärdera om regelbunden träning på kajakergometer resulterar i överföringseffekter på förmågan att utföra funktionella vardagliga moment i rullstolen samt specifika kvalitéer, såsom styrka i skuldermuskulaturen och bålstabilitet i sittande vid olika typer av balansstörningar, hos personer med ryggmärgsskada på bröstryggsnivå.

Syftet var också att studera förmågan att aktivera bålmuskulaturen vid kliniskt komplett (not 1) ryggmärgskada på bröstryggsnivå och undersöka hur bålmuskulaturen används för att stabilisera överkroppen vid olika balansstörningar.

Metod

Tio personer deltog i träningsstudien, 7 män och 3 kvinnor. Samtliga hade en ryggmärgsskada på bröstryggsnivå (T 3-T 12), hade avslutat sin rehabiliteringsperiod och var rullstolsbrukare. Medelåldern för gruppen var 38 år (24-60 år) och antal år efter skadan varierade från 3 till 26 (medianvärde: 12 år).

Under 10 veckor genomförde gruppen 30 träningspass på kajakergometer, som utrustats med den specialutvecklade modulen med reglerbart balanskrav i sidled. Intensiteten och balanskravet ökades successivt under träningsperioden.

Före och efter träningsperioden utfördes mätningar av prestationsförmågan i funktionella tester, maximal styrka i skuldermuskulaturen (i isokinetisk dynamometer) och stabilitet i överkroppen (tredimensionellt röreseutslag i bålen, mätt med ett optoelektroniskt rörelseregistreringssystem) efter balansstörningar åstadkomna genom hastiga förflyttningar av underlaget.

Samtliga tester, förutom styrkemätningen, genomfördes i den egna rullstolen. Efter avslutad träningsperiod fick deltagarna skriftligt utvärdera upplevelsen av träningen med avseende på välbefinnande och funktionsförmåga i vardagliga moment.

I den påföljande fallstudien gjordes mätningar av muskelaktivitet (via ytelektroder applicerade på huden och trådelektroder placerade i muskulaturen) i åtta bålmuskler, dels vid balansstörningar (som ovan), dels vid försök till maximala viljemässiga sammandragningar av respektive bålmuskel hos en person med ryggmärgsskada (vid bröstkota 3, kliniskt klassificerad som komplett) och en icke-skadad person.

Resultat

Träningen i kajakergometer ledde till positiva överföringseffekter på prestationen i funktionella rullstolstester, exempelvis rullstolskörning i uppförsbacke, förflyttning från rullstol till hög brits och ”sit-and-reach” tester, d.v.s. i förmåga att nå så långt som möjligt framför kroppen utan att tappa balansen.

Träningen förbättrade också specifika kvalitéer, som den maximala styrkan i skuldermusklerna och stabiliteten i överkroppen vid balansstörningar. Resultaten från fallstudien visade att personen med hög ryggmärgskada i bröstryggen, klassificerad kliniskt som komplett, kunde aktivera även den bålmuskulatur som innerveras nedanför skadenivån, både vid maximal viljemässig sammandragning och som svar på oförberedda balansstörningar. Däremot skiljde sig aktiveringsmönstret vid balansstörningarna från den icke-skadades.

Slutsats

Baserat på resultaten från träningsstudien kan regelbunden paddling i kajakergometer rekommenderas som träningsform för personer med ryggmärgsskada på bröstryggsnivå. Träningen medförde att deltagarna kunde utföra svårare funktionella moment i rullstolen, vilket i sin tur kan leda till ökad självständighet i det dagliga livet.

Kajakergometerträningen orsakade heller ingen skuldersmärta eller medförde några andra belastningsrelaterade problem. Deltagarna var också positiva till träningsformen och uppgav att de kände ett ökat välbefinnande efter avslutad träningsperiod.

Den påvisade förmågan hos en person med hög ryggmärgsskada i bröstryggen att aktivera sina bukmuskler, pekar på vikten av att inkludera bålmuskulaturen vid klassificering av motorisk funktion och skadenivå. Härigenom ges också en bättre bas för diagnos, prognos och träningsrekommendation.

The purpose of this study was to assess the effects of kayak ergometer training on functional tests performed in wheelchair by persons with spinal cord injury. Ten post-rehabilitated persons with thoracic spinal cord injury volunteered for the study and performed 30 sessions of kayak ergometer training during a 10-week period. The ergometer was modified with an additional balance demand in the medio-lateral direction. Before and after the training period the subjects performed functional tests in the wheelchair: Sit-and-reach tests (distance), mounting a platform, transfer to a bench (height), propelling the wheelchair: 5 m on the rear wheels; in a figure-8; 15 m on a level surface and 50 m on a 3 degrees inclined surface (time). Test-retests were performed for all tests before the training began. A written questionnaire was distributed to evaluate the subjective experiences of the training. The test-retest resulted in coefficient of variation of 1.3 - 4.6 %. There were significant improvements in sit-and-reach (14 %), mounting a platform (7 %), transfer to a bench (10 %), propelling on level (3 %), and inclined surface (6 %). Furthermore, the training, did not cause any shoulder pain or other problems. This, and the positive subjective experience expressed by the subjects after the training indicate that this type of training is a suitable activity for persons with thoracic spinal cord injury.

OBJECTIVES: The objectives of this study were to evaluate biomechanical variables related to balance control in sitting, and the effects of kayak training, in individuals with spinal cord injury. SUBJECTS: Twelve individuals with spinal cord injury were investigated before and after an 8-week training period in open sea kayaking, and 12 able-bodied subjects, who did not train, served as controls. METHODS: Standard deviation and mean velocity of centre of pressure displacement, and median frequency of centre of pressure acceleration were measured in quiet sitting in a special chair mounted on a force plate. RESULTS: All variables differed between the group with spinal cord injury, before training, and the controls; standard deviation being higher and mean velocity and median frequency lower in individuals with spinal cord injury. A significant training effect was seen only as a lowering of median frequency. CONCLUSION: The results indicate that individuals with spinal cord injury may have acquired and consolidated an alternative strategy for balance control in quiet sitting allowing for only limited further adaptation even with such a vigorous training stimulus as kayaking.