Comparing handrim biomechanics for treadmill and overground wheelchair propulsion

Abstract

Study designCross-sectional study.ObjectivesTo compare handrim biomechanics recorded during overground propulsion to those recorded during propulsion on a motor-driven treadmill.SettingBiomechanics laboratory.MethodsTwenty-eight manual wheelchair users propelled their own wheelchairs, at a self-selected speed, on a low-pile carpet and on a wheelchair accessible treadmill. Handrim biomechanics were recorded with an OptiPush instrumented wheelchair wheel.ResultsAcross the two conditions, all handrim biomechanics were found to be similar and highly correlated (r > 0.85). Contact angle, peak force, average force, and peak axle moment differed by 1.6% or less across the two conditions. While not significant, power output and cadence tended to be slightly higher for the treadmill condition (3.5% and 3.6%, respectively), due to limitations in adjusting the treadmill grade.ConclusionBased on the results of this study, a motor-driven treadmill can serve as a valid surrogate for overground studies of wheelchair propulsion.