What reflex does PNF stretching take advantage of to promote muscle relaxation?

PNF stretching, or Proprioceptive Neuromuscular Facilitation, utilizes the Golgi tendon reflex to promote muscle relaxation. When a muscle is stretched, it activates sensory receptors known as Golgi tendon organs found in the tendons. These receptors are sensitive to changes in muscle tension, and when activated, they send signals to the central nervous system to inhibit the muscle's contraction.

This response allows the muscle to relax and lengthen more effectively during the stretching process. In PNF stretching, this is often achieved through a combination of isometric contraction of the muscle being stretched followed by passive stretching, leveraging the feedback from the Golgi tendon organs to enhance the stretch. This physiological mechanism facilitates improved range of motion and flexibility, making PNF an effective technique in rehabilitation and athletic training.