ISOMETRIC, CONCENTRIC CONTRACTIONS
Isometric contraction
is the tension generated is not enough to exceed the resistance of the object to be moved, and the muscle does not change its length. holding the book steady infron of you.
Eccentric
previously shortened bicep lengthens in a controlled manner while it controlled manner while it continues to contract. ex lowering a book.
Isotonic contraction
tension (force or contraction) developed by the muscle remains almost constant while the muscle change its length.
Concentric
the muscle shortens and pulls on another structure such s a tendon to produce movement ex. picking up a book.