If you want to tone and strengthen your quadriceps muscles in the front of your thigh, do leg extensions. You use quadriceps for walking, running, and just about any other activity involving mobility.

Choose a weight that allows you to do 8 to 12 repetitions and sit on the bench with your lower legs behind the padded lever. Hold onto the bench or handles with your hands to keep your upper body in the correct position, and straighten your legs as much as possible. Slowly return to the starting position. Do 8 to 12 repetitions.