JOINT MOMENTS AND PEDALLING RATES IN BICYCLING

Abstract

Joint moments are of interest because they bear some relation to muscular effort and hence rider performance. The general objective o f this study is to explore the relation between joint moments and cadence. Joint moments are computed by modelling the leg-bicycle system as a five-bar linkage constrained to plane motion. Using dynamometer pedal force data and potentiometer crank and pedal position data, system equations are solved on a computer to produce moments at the ankle, knee, and hip joints . Cadence and pedal forces are varied inversely to maintain constant power. Results indicate that average joint moments vary considerably with changes in cadence. Both hip and knee joints show an average moment which is minimum near 105 RPM for cruising cycling. It appears that an optimum RPM can be determined from a mechanical approach for any given power level and bicycle-rider geometry.