Regularly foam rolling the hamstring muscles can help prevent injury. The hamstrings are situated on the back of the thigh and are one of the most commonly strained muscles in the body. In fact, it is the most common injury among footballers, and in many other sports. Hamstring strains usually occur while the muscles are lengthening, for example when you are kicking a football or as your leg is coming forward while sprinting. Therefore, having flexible and elastic hamstring muscles which can adapt better to being stretched while the muscle is contracting will help reduce the risk of injury.