Isometric Muscle Contraction: A type of muscle contraction in which activation of motor units and the production of force does not result in joint motion or a change in muscle length. This occurs when ...

Muscle contraction is the tightening, shortening, or lengthening of muscles when you do some activity. It can happen when you hold or pick up something, or when you stretch or exercise with weights.

Isometric exercises like wall sits, planks, and glute bridges hold the body in one position for a set period of time. Muscles are contracted and engaged, but they don’t lengthen during the exercise.