The hamstring is a biarticular muscle that crosses two joints.  It is composed of three muscles: the semimembranosus, semitendinosus and biceps femoris. The Pendulum Leg Curl was built to target all three parts and has a strength curve that has been designed to match the biomechanical capabilities of the knee flexors.

An advantage in training and rehabilitation utilizing the prone leg curl is the ability to target specific areas of the hamstring musculature.  By internally rotating the feet during the movement there is an increase in the activity of the medial hamstring.  By externally rotating the foot the activity in the medial hamstring is decreased and the activity of the lateral hamstring increased.

Pendulum Prone Leg Curl with Feet in a Neutral Position