Which neural mechanisms contribute to increased range of motion in hold-relax with agonist contraction stretching?

Which neural mechanisms contribute to increased range of motion in hold-relax with agonist contraction stretching?

• A. Autogenic Inhibition and Reciprocal Inhibition
• B. Stretch Inhibition
• C. Reciprocal Inhibition and Crossed-Extensor Inhibition
• D. Autogenic Inhibition and Stretch Inhibition

Answer: (A)

Hold-relax with agonist contraction increases range of motion by engaging two neural pathways. First, when you perform an isometric contraction of the muscle being stretched, the Golgi tendon organ senses the tension and sends Ib afferents that cause autogenic inhibition—reducing the excitability of the motor neurons to that same muscle and allowing it to relax more after the contraction. Then, as you contract the opposing muscle group (the agonist) to move into the new range, reciprocal inhibition kicks in: the activation of the antagonist pathway suppresses the stretched muscle’s motor neurons via interneurons, enabling a greater stretch. Together, autogenic inhibition followed by reciprocal inhibition produces the larger ROM observed with this technique.

Hold-relax with agonist contraction increases range of motion by engaging two neural pathways. First, when you perform an isometric contraction of the muscle being stretched, the Golgi tendon organ senses the tension and sends Ib afferents that cause autogenic inhibition—reducing the excitability of the motor neurons to that same muscle and allowing it to relax more after the contraction. Then, as you contract the opposing muscle group (the agonist) to move into the new range, reciprocal inhibition kicks in: the activation of the antagonist pathway suppresses the stretched muscle’s motor neurons via interneurons, enabling a greater stretch. Together, autogenic inhibition followed by reciprocal inhibition produces the larger ROM observed with this technique.