The ground reaction force (GRF) is the force exerted by the ground on a body in contact with it.
In stance phase, the ground reaction force is aligned as closely to as many joints as possible, minimising the external moments and thus minimising the biomechanical demand on the neuromuscular system. At times the GRF alignment passes from one side of the joint to the other, “switching” the moment.
Page last reviewed: 06 May 2020
