MUSCLES ENGAGED Quadriceps The quadriceps (quads) are a group of four muscles on the front of the thigh. They allow your knee to straighten and provide stability when standing. Your quads are the most important muscle group for maintaining the ability to stand and to walk independently. 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. Equipment Used Bench A weight training bench is a piece of equipment that has a resemblance to a normal (e.g. park) bench, but is cushioned and designed for use in the weight room. Exercise Instructions Step 1 Start in a push-up position on the bench with your back flat, your shoulders lined up over your hands and your feet shoulder width apart. Step 2 Jump up into a standing position and then jump up on to the bench. Make sure to keep your feet should width apart and your hands out in front of you for safety. Step 3 Jump back down to the floor, place your hands on the bench and jump back out into a push-up position.