During PNF stretching, Golgi tendon organs allow the relaxation of the

During PNF stretching, Golgi tendon organs allow the relaxation of the

• A. stretched muscle by contracting the reciprocal muscle
• B. reciprocal muscle by contracting the stretched muscle
• C. reciprocal muscle by its own contraction
• D. stretched muscle by its own contraction

Answer: (D)

Golgi tendon organs trigger autogenic inhibition when the muscle being stretched contracts. In the contract-relax style of PNF, the stretched muscle is held in a contraction against resistance. The increased tension detected by the GTOs in that muscle’s tendon signals the spinal cord to inhibit the muscle’s own motor neurons, causing the stretched muscle to relax. This self-relaxation allows a greater passive stretch in the following phase. This isn’t about the opposite muscle relaxing due to its own contraction (that would be reciprocal inhibition), nor is it about the reciprocal muscle acting under its own contraction. The key point is that the stretched muscle relaxes because its own contraction activates the Golgi tendon reflex, enabling a deeper stretch. This mechanism underpins the contraction-relax approach used in PNF to improve range of motion.

Golgi tendon organs trigger autogenic inhibition when the muscle being stretched contracts. In the contract-relax style of PNF, the stretched muscle is held in a contraction against resistance. The increased tension detected by the GTOs in that muscle’s tendon signals the spinal cord to inhibit the muscle’s own motor neurons, causing the stretched muscle to relax. This self-relaxation allows a greater passive stretch in the following phase.

This isn’t about the opposite muscle relaxing due to its own contraction (that would be reciprocal inhibition), nor is it about the reciprocal muscle acting under its own contraction. The key point is that the stretched muscle relaxes because its own contraction activates the Golgi tendon reflex, enabling a deeper stretch. This mechanism underpins the contraction-relax approach used in PNF to improve range of motion.