Training errors are the most common cause of overuse injuries. These errors involve rapid acceleration of the intensity, duration, or frequency of activity. Overuse injuries also happen in people who are returning to a sport or activity after injury and try to make up for lost time by pushing themselves to achieve the level of participation they were at before injury. Proper technique is critical in avoiding overuse injuries, as slight changes in form may be the culprit. For this reason, coaches, athletic trainers, and teachers can play a role in preventing recurrent overuse injuries. Imbalances between strength and flexibility around certain joints predispose individuals to injury. Body alignment, such as knock-knees, bowlegs, unequal leg lengths, and flat or high arched feet, also impact overuse injuries. Many people also have weak links due to old injuries, incompletely rehabilitated injuries, or other anatomic factors.