MUSCLES ENGAGED 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. Shoulders The shoulder is the most movable joint in the body. However, it is an unstable joint because of the range of motion allowed. This instability increases the likelihood of joint injury, often leading to a degenerative process in which tissues break down and no longer function well. Exercise Instructions Step 1 start in a standing position with your feet shoulder width apart or wider and your hands to your side. Step 2 Keep a soft bend in your knees, bend forward at the waist, reach for the ground and walk out into a push-up position. Step 3 Once in a push-up position, rotate over to one side and reach up for the ceiling. Return to the push-up position and repeat on the other side.