Some Results on the Neuromuscular Controls Involved in Pedaling a Bicycle at Maximum Speed

A series of mathematical models of a human pedaling a stationary bicycle as fast as possible is presented. These models take the form of optimal control problems whose solutions predict the muscle activation, internal and external forces, and limb trajectories that should be observed when humans actually perform the task. The simplest models contain ideal torque generators as actuators so the effects of the underlying limb mechanics are emphasized. For some such models, the controls switch at crank angles that are 180° apart. In contrast, a detailed model that includes muscle dynamics shows that the optimal controls switch in a much more complex manner. The differences provide information about the roles and coordination of different muscles in moving the lower limbs.