The central nervous system has a self-protecting process called neural inhibition. This process keeps muscles from engaging if a voluntary action is causing pain or discomfort. Under the high-impact activities, the central nervous system limits muscular power to protect the skeletal system and joints. The best way to illustrate this is by clenching one’s fist or flexing the muscles to their maximum potential. Under no circumstances can an individual break their own bones. Neural inhibition will not permit it.