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.
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.
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.
Stand with your feet shoulder width apart while holding the dumbbells on your shoulders.
Squat down making sure your hips go below your knees and your back is flat.
Stand up through your heels and press the dumbbells up at the top of the squat. Use your legs to drive the dumbbells up and fully extend your arms at the top of the press.