Overexertion or excessive exertion is when an individual works to the intent that discomfort or injuries result. It is when the body is pushed beyond its ability to cope without hurting muscles or other areas of the body.

Overexertion in the medical literature is shown to be the third leading reason for unintentional injuries in the United States and account for approximately 3.3 million visits to emergency facilities. Whether at home or work, individuals need to take steps to stop or prevent overexertion.

Overexertion can also cause a medical condition known as rhabdomyolysis resulting from muscle injury or from an altered metabolic interaction between energy production and energy consumption by the muscle. Causes can include heat stress, muscle trauma, drug toxicity

Rhabdomyolysis is a medical condition that results from direct injury to the muscle or a transformed metabolic connection between energy production and energy consumption in muscles. Causes consist of heat stress, drug toxicity, muscle trauma and physical exertion. This is rare but often a catastrophic condition where the muscle fibers fail in response to exertion and release products of this breakdown into circulation. Any busy emergency room in a year will treat up to 10 cases of rhabdomyolysis. Cases that are moderate also can be triggered by events of endurance such as marathons, basic military training, and triathlons – or by exercise when a participant is out of shape. In these moderate cases the individuals will have unusually high levels of myoglobin in the blood but insufficient muscle damage to cause kidney failure or insufficiency.

Severe cases of overexertion or rhabdomyolysis can be life threatening.