Mechanical Efficiency of Muscle Use

This is a topic of interest to industrial engineers.

http://sports.jrank.org/pages/9617/mechanical-efficiency.html

The above article points out that up to 40% efficiency can be achieved.
Elite sportsmen are 4 times more efficient compared to novices in net efficiency. Training has market effect on efficiency.

 

Effects of different pedalling techniques on muscle fatigue and mechanical efficiency during prolonged cycling
Abstract of the article