In this study, we examined the relationship between performance and muscle strength of the upper limbs. The muscle strength of the upper limbs is a determining factor of performance for wheelchair marathon racers. Ten wheelchair marathon racers participated in the study, and they were classified into two groups based on their official personal records:six subjects were classified into Group A (<100 min, or 1 hour 40 min) and four subjects were classified into Group B (≥100 min, or 1 hour 40 min). The isokinetic muscle strength during extension and flexion (angular velocity of 60 and 240°/s) of both elbow was measured. The peak torque and peak work of extension for the right elbow (at both angular velocities), the peak work of extension averaged for two elbows (at an angular velocity of 240°/s), the peak torque and peak work of flexion averaged for two elbows (at an angular velocity of 240°/s), the torque acceleration energy of extension and flexion averaged for two elbows (at both angular velocities) and the total work of extension and flexion averaged for two elbows (at an angular velocity of 240°/s) were higher in Group A than in Group B. These results suggest that the maximum muscle strength, instantaneous force, and muscular endurance are the characteristics of the muscle strength of upper limbs which are necessary to ensure high performance for a wheelchair marathon racer.
