This problem was contributed by Carmichael Ong at Stanford University.
An experiment is performed in which a muscle–tendon unit is fixed at some (unknown) length, the muscle is activated to a predetermined level, and the tendon force is measured once the muscle and tendon have reached equilibrium (steady state). The muscle has the following active and passive force–length relationships:
The tendon has the following force–strain relationship:
The muscle and tendon parameters are , , , and pennation .
For each of the following experimental conditions (specified activation and measured tendon force), calculate the length of the muscle and the length of the tendon .
(a) ,
(b) ,
(c) ,
(d) ,