MUSCLES ENGAGED 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. 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. Equipment Used Dumbbells The dumbbell, a type of free weight, is a piece of equipment used in weight training. It can be used individually or in pairs (one for each hand). Dumbbells vary in weight from 3lbs. up to 150lbs. Exercise Instructions Step 1 Start in an athletic stance with your feet slightly wider than shoulder width apart while holding a dumbbell in one hand. Step 2 Keep your chest proud as you bend at the hips and knees until the dumbbell is just above your knees. Step 3 Jump through the balls of your feet and fully extend your hips, knees and ankles and guide the dumbbell over your head and catch it in a quarter squat position.