What action does the semitendinosus muscle perform?

The semitendinosus muscle plays a crucial role in the movement of the thigh and the leg. Its primary functions include extending the thigh at the hip joint and flexing the leg at the knee joint. Additionally, it assists in medially rotating the leg when the knee is flexed. This is important as it allows for a range of movements necessary for activities such as walking, running, and climbing.

Understanding the anatomy and functionality of the semitendinosus helps clarify its multi-faceted role in locomotion and stability. It is part of the hamstrings group, which includes the biceps femoris and semimembranosus, all of which work together to support these actions.

The aspects of flexing and extending provided by the semitendinosus highlight its importance in both the anterior and posterior chains of movement, making it significant for functional activities that require both strength and coordination.