The Biomechanics of Force and Power Production in Human Powered Vehicles

Abstract

There are a large number of factors affecting performance in human powered vehicles (HPV). Designers of HPV's often focus on how resistive forces (friction, drag) can be minimized, as opposed to how propulsive forces can be maximized. How to maximize propulsive forces through vehicle design is not often understood because of a complex interaction between internal biomechanical factors (muscle force/torque/power production) and external mechanical factors (e.g., seat-to-pedal distance, crank arm length, seat-tube angle, backrest angle, chain wheel size). The purpose of this paper is two-fold: (1) to provide information, from a biomechanical and physiological perspective, how muscle force is produced and modified; and (2) to examine how the muscle force produced interacts with external mechanical factors to produce power.