Today i will be telling you types of muscle work:-1) Isometric :- in this type of work the muscles produce energy for doing work without change is the length of muscle i.e. by altering the muscle tone. 2) isotonic:- in this type of work the muscles produce energy for doing work without changing it's tone i.e. by changing the muscle length. 3)concentric:-A contraction that occurs when the muscle shortens. For example, when you lift a heavy weight, your biceps contract concentrically to bend your elbow.4) eccentric:-A contraction that occurs when the muscle lengthens in response to a greater opposing force.