Effects of Powerchair Football: Contextual Factors That Impact Participation.

The aim of this study was to identify contextual factors that negatively affect activity and participation among powerchair football (PF) players. Thirty-seven semistructured interviews were conducted with PF players (Mage = 27.9 ± 8.2 years) in France (n = 18) and the United States (n = 19). Participants reported acute back and neck pain as the primary morbidities resulting from PF participation, with sustained atypical posture in the sport chair as the primary cause. Competition-related physical and mental stress were also identified as participation outcomes. Accompanying the many benefits of PF, participants recognized negative impacts of discomfort, physical fatigue, and mental fatigue. Interventions such as seating modifications, thermotherapy to combat pain, napping to combat acute physical stress, and mental preparation to manage state anxiety were all identified as prospective interventions.

Effect of repeated, on-field sprints on kinematic variables in wheelchair rugby players.

OBJECTIVE: To evaluate the influence of repeated sprints on kinematic performance and propulsion variables during the acceleration and constant peak velocity phases in wheelchair rugby players classified as defensive (LP-D) or offensive players (HP-O). DESIGN: 22 players (13 LP-D and 9 HP-O) performed 6 × 20 m repeated sprint field tests. We calculated peak wheelchair velocities, propulsion phase times, deceleration phase times, cycle times, and left-right velocity asymmetry of the best and last sprints during the acceleration and constant peak velocity phases; the rate of decline in performance variables between the best and the last sprint and a fatigue index. RESULTS: Peak velocities during the acceleration and constant peak velocity phases and mean velocity over the whole sprint were significantly higher during the best than last sprint. Peak velocities were higher during the acceleration and constant peak velocity phases for the best and last sprint for HP-O. The rate of decline in peak velocity during the constant peak velocity phase was higher for LP-D. Fatigue index and rate of decline in velocities and sprint time were higher for LP-D. CONCLUSIONS: Performance variables and the rate of decline in performance variables depended on functional capacity and wheelchair type.

Upper limb cranking asymmetry during a Wingate anaerobic test in wheelchair basketball players.

INTRODUCTION: Interlimb asymmetry of strength and/or motor coordination could limit the performance of wheelchair athletes or increase their risk of injury. Studies of interlimb asymmetry in the lower limbs have shown high between-subject variability that does not depend on the side of dominance and that does not change with fatigue. Upper limb asymmetry is particularly large in manual wheelchair athletes with a lower degree of impairment. The aim of this study was to evaluate interlimb asymmetry of forces developed during an upper limb Wingate anaerobic test, the effects of fatigue on force, and differences between high- and low-point players. METHOD: Twenty-five wheelchair basketball players (13 females and 12 males) of male and female national French teams performed a 30s anaerobic Wingate test on an arm ergometer. Participants were classified into two functional categories, high-point (classed from 3 to 4.5) and low-point (classed from 1 to 2.5), according to the International Wheelchair Basketball Federation classification. Left and right arm forces were measured during the pushing and pulling phases at peak power, 10s, and the end of the 30s test. RESULTS: Upper limb asymmetry changed with fatigue during each phase. Force asymmetry differed between peak power, 10s and 30s, with no consistent increase or decrease. Asymmetry did not differ significantly between low- and high-point players but tended to be greater in high-point players. Asymmetry tended to be greater in the females, with significant differences between the males and females in the push phase. CONCLUSION: Inter-subject variability was high, but forces were asymmetric for most participants, especially females. The Wingate anaerobic test could highlight problematic asymmetries that might impact daily life or sports performance.

Influence of Wheelchair Type on Kinematic Parameters in Wheelchair Rugby.

Introduction: In wheelchair rugby, players use either an offensive or defensive wheelchair depending on their field position and level of impairment. Performance of wheelchair rugby players is related to several parameters, however it is currently unclear if differences in performance are related to wheelchair type or no: the effect of wheelchair type on performance variables has not been evaluated. The aim of this study was to compare offensive and defensive wheelchairs on performance variables during a straight-line sprint. Methods: Thirteen able-bodied people performed two 20 m sprint trials: one with an offensive and one with a defensive wheelchair. Data were collected using inertial measurement units fixed on the wheelchair. Peak wheelchair velocities and left-right asymmetries in peak wheel velocities were measured during the acceleration and constant peak velocity phases. Sprint time, cycle frequency, and mean and maximum velocity were calculated over the entire sprint. Results: The peak velocities of the first 2 pushes (acceleration phase) were significantly higher with the defensive than the offensive wheelchair (p < 0.04 and p < 0.02). Mean and maximum sprint velocity were significantly higher (p < 0.03 and p < 0.04, respectively) with the defensive wheelchair. Cycle frequency and asymmetry did not differ between wheelchairs. Conclusion: Performance was higher with the defensive than the offensive wheelchair, suggesting that the frequent finding that the higher performance of offensive as compared to defensive players is not related to the use of an offensive wheelchair.

Effect of power-assistance on upper limb biomechanical and physiological variables during a 6-minute, manual wheelchair propulsion test: a randomised, cross-over study.

PURPOSE: Use of a power-assistance wheelchair could reduce the risk of musculoskeletal disorders (MSDs), however, a comprehensive biomechanical evaluation of these systems has not been carried out. This study aimed to evaluate and compare biomechanical UL propulsion variables, and physiological exercise-related variables during the use of a wheelchair with rear drive power assist device (RD-PAD) and a standard manual wheelchair (MW). MATERIALS AND METHODS: Twenty-two adults with spinal cord injury were recruited. RD-PAD (SmartDrive system) was fitted to their own MW. An instrumented wheel was used to measure handrim forces, and gas exchange and heart rate were monitored. Participants performed repeated out and back runs for 6 min on a straight outdoor course. RESULTS: Distance covered was significantly greater with the RD-PAD (538 ± 104 m versus 470 ± 124 m). Peak mechanical effort during the propulsion phase was significantly lower with the RD-PAD (p < 0.001). Heart rate, metabolic equivalent of task (MET), tidal volume, minute volume, oxygen consumption, and peak oxygen consumption were all significantly lower with the RD-PAD (p < 0.001). CONCLUSIONS: The results showed that use of RD-PAD increased the distance covered by MW users and reduced the energy costs of propulsion. The biomechanical results indirectly suggest that RD-PAD may reduce the risk of MSD.Implications for RehabilitationUsing the SmartDrive system as propulsion assistance increases the travel autonomy.The SmartDrive system reduces the biomechanical constraints propelling the wheelchair on a slope and low slope.SmartDrive the system reduces the physiological solicitation related to the propulsion of wheelchair.

Performance, asymmetry and biomechanical parameters in wheelchair rugby players.

The practice of the wheelchair rugby is becoming more and more worldwide. However, few biomechanical studies have focused on this sport. The aim of this study was to compare kinematic parameters of wheelchair rugby players, classified as defensive players (LP-D) versus offensive players (HP-O). Twenty-nine wheelchair rugby players (17 LP-D and 12 HP-O) performed a 20-m sprint test. The peak velocities, temporal parameters (propulsion phase time, deceleration phase time, cycle time and cycle frequencies) and asymmetries (the difference in peak velocities between the right and the left wheels) were measured at the acceleration and constant peak velocity phases of the sprint by an inertial measurement unit which was placed on each rear wheel. At the acceleration and constant peak velocity phases, peak velocities and cycle frequencies were higher in HP-O players than LP-D players. The deceleration phase times and the cycle times were higher in LP-D players than HP-O players. However, no significant difference in asymmetry was found between LP-D players and HP-O players. The HP-O players showed superior performance than the LP-D players, but they could be more exposed at risk of injury at their upper limbs than LP-D players.

Does the direct anterior approach allow earlier recovery of walking following total hip arthroplasty? A randomized prospective trial using accelerometry.

INTRODUCTION: In total hip arthroplasty (THA), the anterior approach is attractive, being intermuscular, with theoretic functional benefit. Such benefit has been frequently claimed, but there are few data from randomized comparative studies using more precise metrics than patient satisfaction. We therefore conducted a randomized trial comparing early functional results between anterior and posterior approaches on gait analysis and functional scores. HYPOTHESIS: The study hypothesis was that there is no difference between the two approaches in terms of early recovery of walking. MATERIALS AND METHOD: A single-center single-surgeon prospective randomized study was conducted between February 2017 and April 2018. Inclusion criteria comprised: age<85 years, body-mass index (BMI)<32, and hip osteoarthritis with indication for THA. Preoperatively, the 2 groups were comparable for age, gender, BMI, Charnley, Harris, Postel-Merle-d'Aubigné and Oxford-12 scores and locomotor parameters (triaxial acceleration, step regularity and walking power). Preoperative and 3-, 6- and 12-week assessment comprised triaxial acceleration in walking and Postel-Merle-d'Aubigné, Harris and Oxford SF-12 scores. RESULTS: One hundred patients were randomized to the anterior approach (AA: n=50) and posterior approach (PA: n=50) groups. Hospital stay was comparable between groups: PA, 2.8±1.78 days [range, 2.29-3.31 days]; AA, 2.84±1.25 days [range, 2.48-3.2 days] (p=0.8). Operative time was significantly longer in AA: 70.1±11 minutes vs. 56.7±11.79 (p<0.0001). There were no significant differences in locomotor parameters (p 0.122 to 0.987) or functional scores (p 0.052 to 0.968) over the 3-month follow-up. There was no difference in cup inclination: PA, 39.6±6.87° [range, 37.65-41.55°] vs. AA, 37.74±4.2° [range, 36.55-38.93°] (p=0.09). There were 8/50 cases (16%) of neurapraxia of the lateral cutaneous nerve of the thigh in the AA group; rates for other complications did not differ between groups. CONCLUSION: Early functional results and especially objective locomotor parameters following THA were comparable between anterior and posterior approaches at 3 to 12 weeks. The approach should be chosen according to the surgeon's experience. LEVEL OF EVIDENCE: II, low-power prospective randomized study.

Are there bilateral isokinetic shoulder rotator differences in basketball male players?

BACKGROUND: The internal (IR) and external (ER) rotator shoulder strength are often assess in the upper limb sports to prevent a risk of injuries. The purpose of this comparative study was to measure the agonist/antagonist balance of shoulder strength and to determine whether significant differences exist between the dominant and nondominant sides in basketball players compared to a control groups. METHODS: During the championship, 23 elite male-basketball players (BB) and 23 healthy males (CG) were tested bilaterally on a Cybex Norm isokinetic dynamometer in a seated position with 45° shoulder abduction in the scapular plane at 60°.s-1 and 180°.s-1 in concentric (CON) and 60°.s-1 in eccentric (ECC) modes. RESULTS: No significant differences were found for normalized values to body weight (N.m/kg-1) between the both groups and ER/IR, ECC/CON and functional deceleration ratios were similar. BB have a bilateral difference with higher ER of the dominant side comparatively to the opposite (P<0.05). CONCLUSIONS: Unlike other sports that increase the performance of IR dominant side, the basketball player isokinetic profile could indicate a strengthening in the external rotators of the dominant side. This bilateral difference could be explained by the repetition of the specific movements in the ball control but this was not large enough for the ER/IR ratios to be significantly different with CG. The ratios analysis does not report an imbalance associated with a high risk of shoulder injuries.

The "Picardie en Forme" Network: Federating Regional Health-enhancing Sports Resources / Fédérer les ressources régionales du sport-santé : le réseau Picardie en Forme.

Initiated by the Regional Olympic and Sports Committee and the Regional Directorate of Youth, Sports and Social Cohesion, the "Picardie en Forme" network has been working since 2011 in favour of adults of all ages, with chronic noncommunicable or similar diseases, to encourage a gradual return to reassuring and perennial regular physical activity,. A first step consisted of organizing a care pathway based on two principles: inform general practitioners so that they can encourage their patients to be physically active by referring them to the network, develop a range of local sports by accrediting certain clubs with sports instructors who have been trained in the management of this specific population. In 2013, 121 users entered the network at the request of 61 doctors. 48 sports instructors were trained and 20 associations obtained the Picardie en Forme label. Comparison of the results of tests performed on entry in the network and then eight months later shows a general physical reconditioning of users, increasing their motivation and perceived physical value. However, despite these encouraging results, the network has difficulty retaining users, and maintaining the involvement of general practitioners and certain local partners. This article discusses the relevance of initial approaches and describes the changes made to sustain this regional network, which, for the first time, links sport, health and users.

Effects of modified multistage field test on performance and physiological responses in wheelchair basketball players.

A bioenergetical analysis of manoeuvrability and agility performance for wheelchair players is inexistent. It was aimed at comparing the physiological responses and performance obtained from the octagon multistage field test (MFT) and the modified condition in "8 form" (MFT-8). Sixteen trained wheelchair basketball players performed both tests in randomized condition. The levels performed (end-test score), peak values of oxygen uptake (VO2peak), minute ventilation (VEpeak), heart rate (HRpeak), peak and relative blood lactate (Δ[Lact(-)] = peak--rest values), and the perceived rating exertion (RPE) were measured. MFT-8 induced higher VO2peak and VEpeak values compared to MFT (VO2peak: 2.5 ± 0.6 versus 2.3 ± 0.6 L · min(-1) and VEpeak: 96.3 ± 29.1 versus 86.6 ± 23.4 L · min(-1); P < 0.05) with no difference in other parameters. Significant relations between VEpeak and end-test score were correlated for both field tests (P < 0.05). At exhaustion, MFT attained incompletely VO2peak and VEpeak. Among experienced wheelchair players, MFT-8 had no effect on test performance but generates higher physiological responses than MFT. It could be explained by demands of wheelchair skills occurring in 8 form during the modified condition.

Comparison Between 30-15 Intermittent Fitness Test and Multistage Field Test on Physiological Responses in Wheelchair Basketball Players.

The intermittent nature of wheelchair court sports suggests using a similar protocol to assess repeated shuttles and recovery abilities. This study aimed to compare performances, physiological responses and perceived rating exertion obtained from the continuous multistage field test (MFT) and the 30-15 intermittent field test (30-15IFT). Eighteen trained wheelchair basketball players (WBP) (WBP: 32.0 ± 5.7 y, IWBF classification: 2.9 ± 1.1 points) performed both incremental field tests in randomized order. Time to exhaustion, maximal rolling velocity (MRV), VO2peak and the peak values of minute ventilation (V Epeak), respiratory frequency (RF) and heart rate (HRpeak) were measured throughout both tests; peak and net blood lactate (Δ[Lact(-)] = peak-rest values) and perceived rating exertion (RPE) values at the end of each exercise. No significant difference in VO2peak, VEpeak, and RF was found between both tests. 30-15IFT was shorter (12.4 ± 2.4 vs. 14.9 ± 5.1 min, P < 0.05) but induced higher values of MRV and Δ[Lact(-)] compared to MFT (14.2 ± 1.8 vs. 11.1 ± 1.9 km·h(-1) and 8.3 ± 4.2 vs. 6.9 ± 3.3 mmol·L(-1), P < 0.05). However, HRpeak and RPE values were higher during MFT than 30-15IFT(172.8 ± 14.0 vs. 166.8 ± 13.8 bpm and 15.3 ± 3.8 vs.13.8 ± 3.5, respectively, P < 0.05). The intermittent shuttles intercepted with rest period occurred during the 30-15IFT could explain a greater anaerobic solicitation. The higher HR and overall RPE values measured at the end of MFT could be explained by its longer duration and a continuous load stress compared to 30-15IFT. In conclusion, 30-15IFT has some advantages over MFT for assess in addition physical fitness and technical performance in WBP.

The effect of a one-leg cycling aerobic training program during the rehabilitation period in soccer players with anterior cruciate ligament reconstruction.

OBJECTIVES: To examine cardiorespiratory fitness, resting cardiac parameters, and muscle oxygenation changes in soccer players having undergone anterior cruciate ligament reconstruction and to assess the benefits of a one-leg cycling (OLC) aerobic training program performed during the rehabilitation period. DESIGN: Randomized clinical trial. SETTING: Outpatient clinic, primary care. PATIENTS: Twenty-four, male, regional-level soccer players who had undergone surgical reconstruction of the anterior cruciate ligament of the knee. INTERVENTION: Patients were randomly assigned to 1 of 2 groups: either an individualized OLC aerobic training program with the untreated leg plus a rehabilitation program (training group, TG) or a group that received the same rehabilitation program but without aerobic training (control group, CG). MAIN OUTCOME MEASURES: Outcome measurements assessed before (T1) and after 6 weeks (T2) were stroke volume (SV) and end-diastolic volume (EDV) during resting cardiac echography measurement and peak work rate (W(peak)), peak O(2) uptake (VO(2)peak), peak minute ventilation (VE(peak)), first and second ventilatory threshold (VT1 and VT2), leg muscle oxygenation (LMO(2)), and blood volume (LMBV) during maximal graded tests performed with the untreated leg. RESULTS: At T1, there was no significant difference between TG and CG. For TG, W(peak), VE(peak), VT1, VT2, LMO(2), and LMBV at each work rate were significantly higher at T2 than at T1. For CG, W(peak), VO(2)peak, VE(peak), VT2, SV, and EDV decreased significantly at T2 in comparison with T1. CONCLUSIONS: One-leg cycling training could involve specific adaptations in comparison to a standard rehabilitation program. Moreover, OLC training during rehabilitation seems to stop the effects of hypoactivity.

Effect of one-leg cycling aerobic training in amateur soccer players after anterior cruciate ligament reconstruction.

OBJECTIVE: To examine before and after 6 wks of rehabilitation, the cardiorespiratory fitness, and resting cardiac parameter changes in soccer players having undergone anterior cruciate ligament reconstruction and to assess the benefits of a one leg cycling aerobic training program with the nonsurgical leg during the rehabilitation period. DESIGN: Twenty-four amateur soccer players took part in this study. The subjects were then randomly assigned to one of two groups--either an individualized one leg cycling aerobic program (training group) or without cardiorespiratory training (control group). The initial evaluation (T1) was carried out the first day of rehabilitation and the final evaluation (T2) within 42 days. Both consisted of resting cardiac echography measurement and maximal graded tests performed with the nonsurgical leg. RESULTS: For training group, peak power output, peak minute ventilation, the first (VT1), and second (VT2) ventilatory threshold values were significantly (P < 0.05) higher at T2 than at T1 (+13%, +10%, +7%, and +11%, respectively). For control group, peak power output, peak oxygen uptake, peak minute ventilation, and VT2 values decreased significantly at T2 in comparison with T1(-10%, -10%, -12%, and -11%, respectively). After hospitalization, significant reductions in end diastolic volume (T1, 116 +/- 17 ml; T2, 97 +/- 16 ml; P < 0.05) and stroke volume (T1, 75 +/- 14 ml; T2, 59 +/- 12 ml; P < 0.05) were also observed. For training group, the cardiac parameters were similar between T1 and T2. CONCLUSION: These results suggest that one leg cycling training during the rehabilitation seems to be an adapted method to stop the effects of hypoactivity.

One-leg cycling versus arm cranking: which is most appropriate for physical conditioning after knee surgery?

OBJECTIVE: To compare the cardiorespiratory responses, blood lactate concentration and perceived exertion between 1-leg cycling and arm cranking. DESIGN: Comparison of exercise modalities. SETTING: Hospital. PARTICIPANTS: Fourteen men who had undergone knee surgery were evaluated during rehabilitation. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Each patient performed 2 maximal graded tests: 1-leg cycling and arm cranking exercise, with a 7-day interval. Respiratory gas exchange, heart rate, blood lactate concentration, and the ratings of perceived exertion (RPE) were measured. RESULTS: Peak power output, peak minute ventilation, peak oxygen uptake (Vo(2)peak), and peak heart rate did not differ significantly between 1-leg cycling and arm cranking. The first and second ventilatory thresholds occurred at above 40% and 72% of Vo(2)peak, respectively, in both tests. The maximal lactate concentrations and the RPE values were significantly higher during arm cranking (+10%, +12%, respectively, P<.05) compared with corresponding 1-leg cycling values. CONCLUSIONS: The maximal cardiorespiratory values were not different between arm cranking and 1-leg cycling. However, the RPE and blood lactate concentration were lower when the exercise was performed with the lower limb. Thus 1-leg cycling may be more easily tolerated than arm cranking by patients participating in aerobic conditioning after knee surgery.

Effects of knee surgery on cardiac function in soccer players.

OBJECTIVE: To evaluate the effects of knee surgery on hematocrit and hemoglobin concentration and on resting cardiac parameters as measured by echocardiography. DESIGN: Ten soccer players who underwent knee surgery were evaluated before (T1) and after (T2) hospitalization within a 7-day interval. RESULTS: After hospitalization, end diastolic volume and stroke volume were significantly reduced (P < 0.05) by 14 and 22%, respectively. Despite a significant increase in resting heart rate (T1: 68 +/- 3.3 beats/ min, T2: 72 +/- 3.1 beats/min, P < 0.05), cardiac output was significantly decreased (T1: 4.89 +/- 0.56 liters/min; 3.95 +/- 0.62 liters/min, P < 0.05). The ejection fraction was 65% at T1 and fell to 58% at T2 (P < 0.05). After hospitalization, significant decreases in hemoglobin concentration and hematocrit were observed, suggesting a fall in blood volume. CONCLUSION: In soccer players, knee surgery leads to resting cardiac deconditioning, which is characterized by a significant reduction in stroke volume.

Heart rate variability before and after knee surgery in amateur soccer players.

OBJECTIVE: To analyze the consequences on heart rate variability (HRV) of a hospitalization period due to surgery of the knee in sportsmen. PATIENTS: Ten soccer players who had undergone knee surgery took part in this study. DESIGN: HRV was measured before and after hospitalization within a 7-day interval. RESULTS: After the hospitalization phase, heart rate at rest increased significantly (3 beats/minute). A significant decrease of 7% in the cardiac inter beat interval (R-R interval), P < 0.05 and a 66% decrease in total power spectral density: -66%, P < 0.05 were observed. The disturbance of the autonomic nervous system could be due to a variation in cardiac vagal activity resulting in a 64% decrease in the high frequencies (P < 0.05). This variation was not associated with a modification in normalized markers (LFn.u., HFn.u.) and LF/HF ratio (P > 0.05). CONCLUSION: In sportsmen, a hospitalization period led to an increase in resting heart rate and was associated with a disturbance of the autonomic nervous system.

The effects of rear-wheel camber on the mechanical parameters produced during the wheelchair sprinting of handibasketball athletes.

The wheel camber of a wheelchair is a significant parameter that must be taken into account in the search for optimal regulation of a wheelchair. This study examined the effects of different rear-wheel camber (9 degrees , 12 degrees and 15 degrees )-today used mainly in the handibasket championship-on the various kinetic and kinematic parameters of the propulsion cycle. Eight males, all players in the French handibasket championship, were asked to participate in this study. They performed three 8 s maximal sprints as measured by a wheelchair ergometer, 9 degrees , 12 degrees , and 15 degrees of rear-wheel camber. The results of our study show that residual torque increases in proportion to the increase in wheel camber. This could explain other study results, which show a decrease in mean velocity and an increase in both power output and time of the propelling phase, in relation to the wheel camber. These results should provide the information necessary for optimal wheelchair regulation.