what is the final stage of a typical muscle contraction, ending the contraction?
1 answer
The final stage of a typical muscle contraction, ending the contraction, is called relaxation. During relaxation, the actin and myosin filaments within the muscle fibers slide back apart, reducing the overlap that was created during the contraction phase. This occurs when the nervous stimulation to the muscle ceases, allowing calcium ions to be actively transported back into the sarcoplasmic reticulum. As calcium ions decrease, the binding sites on the actin filaments are blocked again by the tropomyosin, preventing further cross-bridge formation. The muscle returns to its original length and tension decreases, bringing the contraction to an end.