Effects of type and mode of propulsion on hand-cycling biomechanics in nondisabled subjects.

This study investigated the range of motion (ROM) (in degrees) of the upper limb and trunk, forces (Newtons), two-dimensional fraction effective force (FEF(2D)) (in percent), and torque (Newton meters) during hand cycling. Seven nondisabled participants performed a 1 min exercise test at 70 rpm on a hand cycle (HC) fixed to an ergometer in synchronous (SC) mode versus asynchronous (AC) mode and in arm-power (AP) versus arm-trunk-power (ATP) type of propulsion. Higher (p < 0.001) flexion/extension of the trunk was found during ATP versus AP type and higher (p < 0.001) lateral flexion and rotation of the trunk in AC versus SC mode. The trunk ROM should explain the different force generation patterns observed in this investigation between AC and SC modes and AP and ATP types. However, kinetic results do not allow the most effective type or mode of propulsion (FEF(2D): from 72.9% to 89.3%) to be established. We conclude that trunk movement is an important parameter to consider in ergonomically optimizing hand cycling. Nevertheless, future studies in experienced HC users, especially with limited trunk function, should be performed.