Arizona State University (ASU) BIO201 Human Anatomy and Physiology I Exam 3 Practice

Stretching a muscle before stimulation increases twitch strength due to the physiological mechanism known as the length-tension relationship of muscle fibers. When a muscle is stretched, it moves toward an optimal length where actin and myosin filaments overlap most effectively. This optimal overlap allows for a greater number of cross-bridges to form between the filaments upon stimulation.

The result is a more forceful contraction because more units of force can be generated. This improved mechanical advantage translates into stronger contractions, indicating increased twitch strength. Additionally, stretching helps prepare muscle fibers for activation by enhancing their readiness and responsiveness to stimuli, leading to better overall muscle performance.

This relationship is foundational in understanding muscle physiology and fitness training, as optimal stretching can be an essential component of enhancing muscular strength and performance.