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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°, 12° and 15°)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°, 12°, and 15° 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.

The aims of the present study were: first, to assess the interindividual variations of a spontaneously chosen crank rate (SCCR) in relation to the power developed during an incremental upper body exercise on an arm ergometer set at a constant power regime, and second, to compare heart rate (HR) responses, expired minute ventilation (V[E]) and oxygen consumption (VO2) when the pedal rates were chosen spontaneously (T[SCCR]) or set at +/- 10% of the freely chosen rates (T[+10%] and T[-10%], respectively). The mean pedal rate values were linearly related (P < 0.01) with the power developed during arm cranking (r = 0.96), although large variations of pedalling rate strategies were observed between subjects. Maximal power (MP) and time to exhaustion values were significantly higher (P < 0.05) during T(SCCR) than during T(+10%) and T(-10%). Peak VO2 values were significantly higher (P < 0.05) in T(+10%) than in T(SCCR) and T(-10%). The increase in HR, V(E), and VO2 mean values, in relation to the increase in the power developed, was significantly higher (P < 0.05) when the pedal rate was set at plus 10% of the SCCR (T[+/-10%]) than in the two other conditions. The findings of the present study suggest that the use of an electromagnetically braked ergometer, which automatically adjusts the resistance component to maintain a constant work rate, should be used in order to achieve the highest MP values during an incremental upper body exercise. A 10% increase of the SCCR should be used in order to provide the highest peak VO2 value.