The hamstring muscle group comprises biceps femoris muscle, semitendinosus muscle, and semimembranosus muscle. These muscles are located at the back of the thigh. Since tight hamstrings can put one at a risk of muscle strains or injuries, one must perform exercises to strengthen these muscles and improve flexibility. While doing so, it is important to follow the right technique to get better results and avoid an injury. Here are some exercises that you could perform.