The hamstrings are a group of muscles and their tendons at the rear of the upper leg. They include the biceps femoris, semitendinosus, and semimembranosus. The hamstrings flex the knee joint and extend the thigh to the back side of the body. They are used in walking, running, and many other physical activities.
In human anatomy, a hamstring (/ ˈ h æ m s t r ɪ ŋ /) is any one of the three posterior thigh muscles in between the hip and the knee (from medial to lateral: semimembranosus, semitendinosus and biceps femoris). The hamstrings are quite susceptible to injury. In quadrupeds, the hamstring is the single large tendon found behind the knee or comparable area.
The semitendinosus muscle is located between the semimembranosus and biceps femoris at the back of your thigh. It begins at the pelvis and extends to the tibia. It’s the longest of the hamstrings….
The hamstring muscles are a group of three muscles located on the back of your thigh. The three muscles are called the biceps femoris, the semimembranosus, and the semitendinosus. These three muscles work together to help bend your knee. They can also help with hip extension, when your hip and thigh move towards the back of your body. 1
As we already mentioned, the hamstrings are a group of three muscles that run down the back of your thigh. Their main function is to move your hip and knee. All of the hamstring muscles begin from the bottom part of your pelvis called the Ischial Tuberosity, or the sit bone. They run across the knee and attach to your lower leg.