During self-myofascial release (SMR), what gets activated when forced manual pressure creates an increase in muscle tension at a location?

During self-myofascial release (SMR), the activation of Golgi tendon organs occurs when forced manual pressure creates an increase in muscle tension at a specific location. Golgi tendon organs are specialized mechanoreceptors located at the junction between muscles and tendons. Their primary function is to monitor tension within the muscle-tendon unit.

When a muscle is subjected to increased tension—such as during SMR—the Golgi tendon organs detect this heightened tension and relay this information to the central nervous system. This process facilitates a reflex response that ultimately leads to muscle relaxation through an inhibition of the alpha motor neurons, which control muscle contraction. This is crucial for releasing tightness and promoting flexibility, effectively aiding in recovery and improving overall function.

In this context, while muscle spindles also play a role in sensing stretch and contraction, their primary function is to respond to changes in muscle length rather than tension. Extrafusal fibers are the main muscle fibers responsible for contraction but do not have a direct role in sensing tension during SMR. Alpha motor neurons transmit signals to stimulate muscle contraction, but the key aspect of tension monitoring and relaxation in SMR specifically involves the action of the Golgi tendon organs.