MUSCLES ENGAGED Glutes Gluteal Muscles (Glutes) are one of the strongest muscles in the body and are the connecting point between your legs and back muscles. Glutes are used in a variety of actions from moving the leg to extending and rotating the hip, as well as extending and rotating the trunk of the body. Hamstrings The hamstrings play a crucial role in many daily activities, such as, running, jumping, walking and cycling. Strengthening your hamstring muscles help to protect your knees from injury by absorbing the stress placed on the knee. Weak hamstrings can lead to knee injury. Exercise Instructions Step 1 Start on your back with your knees bent. Step 2 Cross one leg over the other, reach through and grab behind your hamstring. Step 3 Pull both legs up off of the floor until your feel a gentle stretch in your glutes.