isometric exercise, a form of active exercise in which muscle tension is increased while pressure is applied against stable resistance. This exercise may be accomplished by pushing or pulling against an immovable object or by simultaneously contracting opposing muscles, such as by pressing the hands together. There is no joint movement, and muscle length remains unchanged, but muscle strength and tone are maintained or improved. Compare isotonic exercise. See also exercise.
Isometric exercise (Patton and Thibodeau, 2016)