Plies vs. Deep Knee Bends

"Plie" is a ballet term that means "bent" in French. Deep knee bends are squats you do with your legs at hip width apart and your feet and hips facing forward. On the other hand, the plie is a knee bend done with the feet and hips turned out. While both exercises work your thighs and butt, they work different muscles. Doing both exercises would optimize any leg strengthening workout. However, deep knee bends are a controversial exercise; talk to your doctor or fitness trainer before doing them, especially if you have weak knee joints.

To do plies to work out your legs, stand in ballet's second position, in which your legs are a little wider than hip-width's distance. Turn your hips out, rotating them as far as they can go open and apart from each other. Tighten your abdominals to keep a flat back as you bend your knees. Lower your torso directly down and make sure your knees do not reach over your toes. Push your heels down to the floor and straighten your legs to return to your standing second position. You can hold your arms straight out to the side with your shoulders pressing down, or you can raise your arms over your head as you bend and lower them as you straighten. Repeat for 20 reps.

Deep knee bends involve bending into a deep squat position and standing up again repeatedly. Stand with your feet at hip-width distance. You can have your feet and hips facing straight forward or have them slightly turned out if it feels more natural to you. Tuck in your abdominals and straighten your spine. Hold your arms out in front of you. Bend at your knees while pushing your heels off the floor. Lower yourself as much as possible without letting your back bend. Use your abs to help you balance on the balls of your feet. Straighten to return to standing position. Repeat the desired number of reps. Do not add weight; your own body weight should be your only resistance.

Plies sculpt your inner thighs and firm your glutes, giving you lean and strong dancer's legs. Doing them is safer for the knees, because your legs are wider apart. If you have weak knees and would like to work out your legs without putting strain on your knees, doing plies is a good exercise for you. Another benefit to plies is that you can hold free weights or a barbell to increase resistance. Avoid adding weight with deep knee bends, which already put stress on the knees and should be done with caution.

Deep knee bends target your quadriceps, the large muscle group on the front of your thighs. A major benefit to deep knee bends is that you will improve your ability to squat and bend doing daily activities. If you have difficulty turning your hips out for plies, deep knee bends might be better for you.

Deep knee bends are a safety concern, according to Physed.com. Though good for strengthening the legs, they cause hyperextension, stretching, compression and stress to your knees. A safe alternative to deep knee bends is the forward lunge. Take a step forward with your right foot and place your left knee on the floor. Most of your weight should be on your right leg, which should be bent at a 90-degree angle. Hold and repeat with the left foot to strengthen your quads, hips and hamstrings. Let your leg muscles rest at least 48 hours before doing these exercises again. Without this recovery time, your muscles won't be able to rebuild and grow stronger. Stay hydrated by drinking water before and after your workouts. Massage sore muscles and eat foods high in protein to help them heal faster.

At the end of the day, you're aiming to tone up your leg muscles by doing squat exercises that target those muscles. Remember that plies and deep knee bends work different muscles in your legs; plies target the inner thighs and glutes, and deep knee bends target your quads. If you're an athlete or you're in good physical shape, with no knee injuries or weight problems, the deep knee bend might be a safe and effective exercise for your quads. In this case, you would benefit from doing both plies and deep knee bends within the same workout routine, so that you work more muscle groups on your legs. Otherwise, find safer exercises that target your quads and other leg muscles -- for instance, the dumbbell squat. Add other leg exercises that work the calves, hamstrings and hips to the plies and deep knee bends to get a full leg workout. A major benefit to exercising your legs with squats and other resistance exercises is building muscle, since muscle mass burns fat even when you're not working out.