Table of Contents

Human Power and Propulsion




For short sprints, The stored muscle energy source, ATP (andosine tri-phosphate), can supply the needed energy in an anaerobic (non-oxygen consuming) process. As the time of pedaling increases, oxidation products (lactic acid) build up in the muscles and fatigue starts to decrease the sustainable power. At long times the steady state energy conversion process must become aerobic.

The diagram shows the results of several different measurements of human power output as a function of time.
The blue line indicates that 100 Watts is the maximum healthy person steady state power output that can be relied upon.

From: Abbott & Wilson, "Human-Powered Vehicles," Human Kinetics (1995)