The hamstring stretches are designed to improve the flexibility of the hamstring muscles and are important to maintain balance between strength and flexibility.
The large posterior thigh muscles—biceps femoris, semimembranosus, and semitendinosus—are collectively called the hamstring muscles, and these are the major knee flexors. The hamstrings are assisted in knee flexion by the gracilis and sartorius on the medial side of the thigh and the gastrocnemius, popliteus, and plantaris on the posterior side of the lower leg.
It is important, however, to have the right balance of strength and flexibility between the opposing muscle groups of the thigh.
Following are the different hamstring stretches in different body positions
Standing hamstring stretch
Hamstring stretch forward bend
Hamstring wall stretch
Hamstring stretch with towel
Kick up hamstring stretch