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Goosey-Tolfrey V.,Loughborough University | Foden E.,Manchester Metropolitan University | Perret C.,Institute of Sports Medicine | Degens H.,Manchester Metropolitan University
British Journal of Sports Medicine | Year: 2010

Background: There is considerable evidence that respiratory muscle training improves pulmonary function, quality of life and exercise performance in healthy athletic populations. The benefits for wheelchair athletes are less well understood. Therefore, in the present study, influence of inspiratory muscle training (IMT) on respiratory function and repetitive propulsive sprint performance in wheelchair basketball players was examined. Methods: Using a placebo-controlled design, 16 wheelchair athletes were divided to an experimental (IMT; n = 8) or placebo (sham-IMT; n=8) group based on selective grouping criteria. 30 dynamic breaths were performed by the IMT group twice daily at a resistance equivalent to 50% maximum inspiratory pressure (MIP), and 60 slow breaths were performed by the sham-IMT group once a day at 15% MIP for a period of 6 weeks. Results: In the IMT group, both MIP and maximum expiratory pressure (17% and 23%, respectively; p(≤0.03) were improved. Similar improvements were noted for the sham-IMT group with 23% and 33% from baseline for MIP and maximum expiratory pressure, respectively (p≤0.03). There were no significant changes in pulmonary function at rest and any of the performance parameters associated with the repetitive sprint test (sprint and recovery times, peak heart rate and peak blood lactate concentration). Reported experiences of using the IMT training device suggested "less breathlessness" and "less tightness in the chest during the training". Conclusions: Although there was no improvement in sprint performance, an improved respiratory muscle function and quality of life were reported by participants in both the IMT and sham-IMT groups. Source

Perret C.,Institute of Sports Medicine
Disability and Rehabilitation | Year: 2015

Purpose: Elite-adapted sports performance has considerably improved over the last decades and winning or losing races at Paralympic Games is often a matter of a split second. In other words, every single detail counts, which underlines the necessity of optimizing training interventions and equipment for athletes in order to achieve top-class performance. However, to date, studies which include Paralympic elite athletes are scarce. Methods: A comprehensive literature search was performed to identify potential strategies and interventions in order to optimize elite-adapted wheelchair sports performance, whereas the focus lay on respiratory muscle training (RMT), cooling (CI) and nutritional interventions (NI) as well as on individual equipment adaptations (IEA). Results: The total number of studies identified for the final analysis was six for RMT, two for CI, three for NI and seven for IEA, respectively. Results point predominantly towards performance enhancing benefits for CI and IEA, whereas NI and RMT provided inhomogenous findings. Conclusions: In comparison to the able-bodied population, research in the field of Paralympic elite sport is scarce. CI and IEA seem to have significant performance enhancing benefits, whereas NI and RMT revealed controversial findings. However, due to the limited number of elite athletes with a spinal cord injury available to participate in scientific studies, general conclusions are difficult to make at this stage and in daily practice recommendations are still given mainly on an individual basis or based on personal experiences of coaches, athletes and scientists.Implications for RehabilitatonBased on the knowledge gained in elite sports, wheelchair equipment could be optimized also for daily use.Elite sports performance could inspire wheelchair users to achieve their personal fitness goals. © 2015 Taylor & Francis Source

Labruyere R.,ETH Zurich | Perret C.,Institute of Sports Medicine
International Journal of Sports Medicine | Year: 2012

The aim was to investigate whether the level of lactic acidosis in the first part of a heart rate-based lactate minimum test affects the lactate minimum heart rate and performance. We tested 15 men (age: 31±6 years, height: 179±6cm, body mass: 75.6±7.6kg and VO 2peak 50.3±10.0ml·min -1·kg -1). They all completed 2 lactate minimum tests following 2 different protocols during the first part of the test, i.e., i) a maximal test until exhaustion to provoke extensive lactacidaemia and ii) a submaximal test abandoned 3 stages earlier than the maximal test to provoke significantly lower but still considerable lactacidaemia. The second part of the lactate minimum test was identical for both runs. It consisted of a heart rate-based incremental test to determine the lactate minimum and the corresponding lactate minimum heart rate and performance. Results showed a significantly higher maximal blood lactate concentration at the end of the maximal test compared to the submaximal test (9.7±2.7 vs. 6.0±2.0mmol·l -1, P<0.001). Also mean lactate minimum heart rate (160±12 vs. 144±13bpm, P<0.001) and performance (200±40 vs. 170±35W, P<0.001) were significantly higher after the maximal test compared to the submaximal test. We conclude that the first part of the heart rate-based lactate minimum test needs to be performed until exhaustion to receive reliable and meaningful results. © Georg Thieme Verlag KG Stuttgart New York. Source

Malliaras P.,Queen Mary, University of London | Barton C.J.,Queen Mary, University of London | Reeves N.D.,Manchester Metropolitan University | Langberg H.,Institute of Sports Medicine
Sports Medicine | Year: 2013

Introduction: Achilles and patellar tendinopathy are overuse injuries that are common among athletes. Isolated eccentric muscle training has become the dominant conservative management strategy for Achilles and patellar tendinopathy but, in some cases, up to 45 % of patients may not respond. Eccentric-concentric progressing to eccentric (Silbernagel combined) and eccentric-concentric isotonic (heavy-slow resistance; HSR) loading have also been investigated. In order for clinicians to make informed decisions, they need to be aware of the loading options and comparative evidence. The mechanisms of loading also need to be elucidated in order to focus treatment to patient deficits and refine loading programmes in future studies. Objectives: The objectives of this review are to evaluate the evidence in studies that compare two or more loading programmes in Achilles and patellar tendinopathy, and to review the non-clinical outcomes (potential mechanisms), such as improved imaging outcomes, associated with clinical outcomes. Methods: Comprehensive searching (MEDLINE, EMBASE, CINAHL, Current Contents and SPORTDiscus ™) identified 403 studies. Two authors independently reviewed studies for inclusion and quality. The final yield included 32 studies; ten compared loading programmes and 28 investigated at least one potential mechanism (six studies compared loading programmes and investigated potential mechanisms). Results: This review has identified limited (Achilles) and conflicting (patellar) evidence that clinical outcomes are superior with eccentric loading compared with other loading programmes, questioning the currently entrenched clinical approach to these injuries. There is equivalent evidence for Silbernagel combined (Achilles) and greater evidence for HSR loading (patellar). The only potential mechanism that was consistently associated with improved clinical outcomes in both Achilles and patellar tendon rehabilitation was improved neuromuscular performance (e.g. torque, work, endurance), and Silbernagel-combined (Achilles) HSR loading (patellar) had an equivalent or higher level of evidence than isolated eccentric loading. In the Achilles tendon, a majority of studies did not find an association between improved imaging (e.g. reduced anteroposterior diameter, proportion of tendons with Doppler signal) and clinical outcomes, including all high-quality studies. In contrast, HSR loading in the patellar tendon was associated with reduced Doppler area and anteroposterior diameter, as well as greater evidence of collagen turnover, and this was not seen following eccentric loading. HSR seems more likely to lead to tendon adaptation and warrants further investigation. Improved jump performance was associated with Achilles but not patellar tendon clinical outcomes. The mechanisms associated with clinical benefit may vary between loading interventions and tendons. Conclusion: There is little clinical or mechanistic evidence for isolating the eccentric component, although it should be made clear that there is a paucity of good quality evidence and several potential mechanisms have not been investigated, such as neural adaptation and central nervous system changes (e.g. cortical reorganization). Clinicians should consider eccentric-concentric loading alongside or instead of eccentric loading in Achilles and patellar tendinopathy. Good-quality studies comparing loading programmes and evaluating clinical and mechanistic outcomes are needed in both Achilles and patellar tendinopathy rehabilitation. © 2013 Springer International Publishing Switzerland. Source

Flueck J.L.,ETH Zurich | Mettler S.,ETH Zurich | Perret C.,Institute of Sports Medicine
International Journal of Sport Nutrition and Exercise Metabolism | Year: 2014

The aim of this study was to investigate whether caffeine and/or sodium citrate have an ergogenic effect on the 1,500-m exercise performance in elite wheelchair athletes. A placebo-controlled, randomized, cross-over and double-blind study design was conducted with the four treatments placebo, caffeine, sodium citrate and the combination of caffeine and sodium citrate. Nine healthy, elite wheelchair-racing athletes (median: [min; max] age: 28 y [23; 54]; height: 173 cm [165; 188]; weight: 62.9 kg [48.9; 68.4], category T53/54) completed the study. All athletes were national team members, including several Paralympic Games, World and European Championship medalists. The athletes performed a 1,500-m time trial four times on a wheelchair training roller. Time to complete 1,500-m, pH, bicarbonate and sodium concentration as well as lactate concentration were measured. The time to complete 1,500-m was not significantly different between the four treatments (placebo: 170.6 s [141.7; 232.0]; caffeine: 179.5 s [134.8; 239.6]; sodium citrate: 178.3 s [136.4; 247.1]; combination: 177.6 s [136.1; 256.2]). However, pH and bicarbonate concentrations were significantly increased with sodium citrate ingestion compared with placebo. Moreover, maximal lactate concentrations were significantly higher in the caffeine and the combination treatment compared with placebo. The supplementation with sodium citrate and/or caffeine did not provide an ergogenic effect on the 1,500-m exercise performance in wheelchair elite athletes. © 2014 Human Kinetics, Inc. Source

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