The hamstrings are muscles located on the back of the legs. Hamstrings help create the movements for bending and flexing the knee and extending the leg. A hamstring can be injured by overstretching and tearing a muscle or by continually dancing with poor alignment. Hamstring tears are common in ballet because of the extreme flexibility required in classical ballet choreography. Modern dancers can pull hamstrings while performing or rehearsing unconventional choreography.
An injury to the hamstring can sideline a dancer's career or study time. An injury on one leg can create asymmetry and lead to further injuries if the dancer tries to compensate for a weaker side. Going back to class or performance too soon can exacerbate this problem. A pulled hamstring can result in scar tissue that can decrease flexibility even after the muscle tear has healed. Sports massage can help prevent such muscle tissue scars. Hamstring injuries are generally not serious but it is important to let injured muscles rest before returning to class.
In "How to Dance Forever," Daniel Nagrin warns against the dangers of poor dance form and inadequate teaching. He comments on the fact that although young dancers may not know they are dancing with bad form if they feel no pain, continuous poor form can cause chronic problems as the dancer ages. It is important to study with an experienced teacher who can observe whether a dancer has the right posture while dancing.
Overuse of the hamstring is a common cause for injuries. Even when dancing with correct form, the combination of dancing too much and not resting enough can lead to chronic pain and injury. Eric Franklin, creator of "the Franklin Method," advises that every dancer should limit her class time to three hours a day and suggests practicing a dance conditioning method three times a week.
Boyd Bender, a physical therapist who works with the Pacific Northwest Ballet in Seattle, suggests strengthening the hamstrings in order to avoid injuries. He states that the quadriceps and hamstrings work together to perform certain moves. Strengthening the hamstrings is important so they can properly work with the quadriceps. Movement therapies such as Pilates and the Gyrotonic method include machine work with leg straps. These exercises help isolate the movements of the hamstring and help the dancer become aware of which leg muscles he is using. He can adapt this knowledge to movements in dance class and will be less likely to sustain an injury.