Anatomy of the Hamstrings
With the exception of the short head of the biceps femoris, the hamstring complex begins at the ischial tuberosity (sit bone) and end below the knee on the inside part of the leg bone. The proximal (beginning part) of the hamstring complex has a strong bony attachment on the ischial tuberosity (sit bone) (Figure 1).
Their footprint on the ischium is made up of the semitendinosus and the long head of biceps femoris beginning as a common proximal tendon and footprint, and a separate semimembranosus footprint.
FIGURE 1: Hamstring Anatomy at the Ischial Tuberosity