The up phase of a wide arm push-up creates which type of contraction of the bicep muscle?

In the up phase of a wide arm push-up, the bicep muscle performs a concentric contraction. This type of contraction involves the shortening of the muscle as it generates tension and works to lift the body away from the ground. During this phase, the biceps are assisting in stabilizing and maintaining the position of the arms as the body rises, causing the muscle fibers to contract and shorten effectively to support this movement.

While isometric contractions occur when a muscle generates tension without changing length, such as holding a position, the bicep is actively shortening during the push-up. Eccentric contractions involve lengthening of the muscle under tension, typically occurring when lowering the body, which is not applicable in the up phase. Auxotonic refers to the simultaneous lengthening and shortening of muscle fibers, which also doesn't accurately describe the uniform contraction occurring in the biceps during this phase.