The Golgi Tendon Organ (GTO) inhibition is one of enduring myths of vertical jump and strength training. To find out the truth about what it is and what it does, here is a little bit of GTO myth busting.
The golgi tendon organ is a tendon that is located in the muscle-tendinous junction. Its job is to sense tension in the muscles. As you contract or stretch a muscle the golgi tendon organ senses the force of the contraction or stretch and sends signals to the brain about the level of overload so that the brain can then fire the muscles accordingly.
According to the commonly held theory, if it senses excessive tension it kicks in to limit your body's ability to produce more muscle tension, hence the phrase GTO inhibition. The belief is that this is a protective mechanism that prevents you from being able to hurt yourself with excessive muscular contractions beyond what your body can handle.
The off shoot of this is that if you are experiencing GTO inhibition you cannot contract your muscles with as much power as you want which obviously means you can't jump as high. So if this theory is true, what can you do to reduce its effects and increase your jump?
The general view is that by performing regular high force high velocity contractions such as plyometrics and heavy weighted exercises you can teach your body to reduce GTO inhibition and therefore allow it to maximize the (also over stated) benefits of the stretch shorten cycle.
If you believe the previous paragraph then you would say yes, GTO inhibition can negatively impact your jump. However what the commonly held belief says and what science says are two different things entirely.
According to research there is no experimental evidence to support the idea that strength and plyometric training may produce a decrease in GTO inhibition, nor is there any research that suggests that the golgi tendon organ actually inhibits the muscles from contracting that much in the first place.
Not only that but the research also suggests that a reduction in muscle contraction force from stretch reflexes following a contraction of a stretched muscle are NOT due to the activation of Golgi tendon organs, as commonly purported, but instead may be due to presynaptic inhibition of the muscle spindle sensory signal.
This is in line with earlier studies done by a researcher named Crago who discovered that the golgi tendon organ is not as powerful at inhibiting muscle activation as many in the fitness industry believe and often sprout as gospel.
Not a great deal actually. It just means that the next time a vertical jump guru tells you that performing 'true' or 'shock' plyometrics is a great way to train your body to maximize the benefits of the stretch reflex and minimize the actions of the golgi tendon organ, well they don't actually know as much as they think they do.
You should definitely still do your plyometric exercises and jumping drills, as well some basic strength training to increase force production, but in terms of reducing GTO inhibition, don't lose too much sleep over this.
Gordon Chalmers, Do Golgi tendon organs really inhibit muscle activity at high force levels to save muscles from injury, and adapt with strength training?, Sports Biomechanics, Volume 1, Issue 2 July 2002 , pages 239 - 249
Gordon Chalmers, Re-examination of the possible role of Golgi tendon organ and muscle spindle reflexes in proprioceptive neuromuscular facilitation muscle stretching. Sports Biomechanics, 2004 Jan;3(1):159-83
Crago, P. E., Houk, J. C., and Rymer, W. Z., (1975). Influence of motor unit recruitment on tendon organ discharge. Neuroscience Abstracts, 1: 280.