How its done. Muscle contractions can be divided into: •isotonic (constant tension through rom-range of motion) basically but not exactly like free wts. Most effect on weakest point •isometric (no movement) •isokinetic (motion is at aconstant speed but the force varies) requires complicated special equipment but does strengthen the muscle through its entire range equally.
Motion-No Motion. Isometric exercise is where muscle force is exerted without changing the length of the muscle fibers. This is 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. Isotonic occurs when a contracting muscle shortens against a constant load, as when lifting a weight.