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. Exercise Instructions Step 1 start in a standing position with your feet shoulder width and your hands to your side. Step 2 Jump down to the bottom of a push-up position making sure your chest and thighs touch the ground. Step 3 Stand back up and jump in the air fully extending your ankles, hips and knees.