What is the exercise where force is exerted against an unmoving object?

Exercises in which force is exerted against an unmoving object are referred to as isometric exercises. In such exercises, there is no noticeable change in the length of the muscle, and the joint involved does not move.

Since isometric exercises help maintain body strength without moving the joint, they are especially important in rehabilitative training because an injured joint is not affected. Some isometric exercises are sub-maximal, meaning that less than maximum muscle strength is required to hold a weight at a certain elevation. Others are maximal, such as pushing against a solid wall, and maximum muscle strength can be applied against the immovable object.