Bioenergetics and Biomechanics of Handcycling at Submaximal Speeds in Athletes with a Spinal Cord Injury

The relation between sprint power and road time trial performance in elite para-cyclists

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.

Physiological responses during simulated 16 km recumbent handcycling time trial and determinants of performance in trained handcyclists

Purpose

To characterise the physiological profiles of trained handcyclists, during recumbent handcycling, to describe the physiological responses during a 16 km time trial (TT) and to identify the determinants of this TT performance.

Methods

Eleven male handcyclists performed a sub-maximal and maximal incremental exercise test in their recumbent handbike, attached to a Cyclus II ergometer. A physiological profile, including peak aerobic power output (PO_Peak), peak rate of oxygen uptake (\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\dot{V}$$\end{document}V˙O_2Peak), aerobic lactate threshold (AeLT) and PO at 4 mmol L⁻¹ (PO₄), were determined. Participants also completed a 16 km simulated TT using the same experimental set-up. Determinants of TT performance were identified using stepwise multiple linear regression analysis.

Results

Mean values of PO_Peak = 252 ± 9 W, \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\dot{V}$$\end{document}V˙O_2Peak = 3.30 ± 0.36 L min⁻¹ (47.0 ± 6.8 mL kg⁻¹ min⁻¹), AeLT = 87 ± 13 W and PO₄ = 154 ± 14 W were recorded. The TT was completed in 29:21 ± 0:59 min:s at an intensity equivalent to 69 ± 4% PO_Peak and 87 ± 5% \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\dot{V}$$\end{document}V˙O_2Peak. PO_Peak (r = − 0.77, P = 0.006), PO₄ (r = − 0.77, P = 0.006) and AeLT (r = − 0.68, P = 0.022) were significantly correlated with TT performance. PO₄ and PO_Peak were identified as the best predictors of TT performance (r = 0.89, P < 0.001).

Conclusion

PO_Peak, PO₄ and AeLT are important physiological TT performance determinants in trained handcyclists, differentiating between superior and inferior performance, whereas \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\dot{V}$$\end{document}V˙O_2peak was not. The TT took place at an intensity corresponding to 69% PO_Peak and 87% \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\dot{V}$$\end{document}V˙O_2peak.

Assessment of the Relationship between Selected Factors and Stress-Coping Strategies in Handcyclists-A Preliminary Study

Background and Objectives: Playing competitive sports is associated with stress, especially during the starting season. Disabled athletes are additionally burdened with physical and/or emotional factors, resulting from the trauma they have experienced. The aim of the work was to assess the relationship between strategies of coping with stress and the level of education, category of disability and its duration of handcyclists before the competition. Materials and Methods: 44 handcyclists with a mean age of 41.8 ± 11.6, from European countries, were divided according to the severity of mobility impairments, education and duration of the disability. The participants were asked to fill in the Mini-COPE Inventory for Measuring Coping with Stress, which provided answers in writing to some sociodemographic questions regarding age, sex, education, type of mobility impairment and duration of the disability. Results: The subjects who had suffered spinal injury at the cervical section obtained the lowest scores regarding their subjective assessment of their active stress management in difficult situations (p = 0.007). They scored the lowest, 1.5 points, when asked about acceptance in difficult circumstances compared to those with university education (p = 0.02). A statistically significant correlation was found to exist between education levels and positive revaluation, acceptance and seeking instrumental support. A negative correlation was observed between education and sustained use of psychoactive substances and denial. Conclusions: Highly educated cyclists with short-lasting disability, damage to the lower spine section or amputations tend to cope better with stress than other study participants.