Common misconceptions

Many myths have arisen surrounding exercise, some of which have a basis in reality, and some which are completely false. Myths include:

That excessive exercise can cause immediate death.[citation needed] Death by exercise has some small basis in fact. Water intoxication can result from prolific sweating (producing electrolyte losses) combined with consumption of large amounts of plain water and insufficient replenishment of electrolytes, especially salt and potassium (e.g. when running a marathon). It is also possible to die from a heart attack or similar affliction if overly intense exercise is performed by someone who is not at an appropriate level of fitness for that particular activity or has an undiagnosed rare condition like hypertrophic cardiomyopathy.

A doctor should always be consulted before any radical changes are made to a person's current exercise routine. Rhabdomyolysis is also a risk. Other common dangers may occur from extreme overheating or aggravation of a physical defect, such as a thrombosis or aneurysm.

That weightlifting makes you short or stops growth. One confirmed danger is that heavy weight training in adolescents (ages 11–16) can damage the epiphyseal plate of long bones and can stunt joints..[citation needed] It is still commonly suggested that adolescents refrain from any kind of "strenuous" weight-lifting. However, weight training is a healthy form of exercise for adolescents and can be perfectly safe if performed under the supervision of a trained professional