To keep your body looking and feeling its best with each passing year, say "om." Studies have shown that doing yoga is one of the greatest ways to slow the clock. And it's not just because you're helping your muscles remain limber—a regular yoga practice may increase the levels of stay-young hormones that can slow the aging process.

"As you get older, you lose lean muscle mass—as much as 15 percent per decade if you're not active," says Vonda Wright, MD, an orthopedic surgeon and the author of Fitness After 40. But doing yoga plus other strength exercise at least four or five times a week helps slow this loss so that even a 60-something can have as much lean muscle mass as someone 20 years younger, she adds.

Yoga is also especially good at battling the sag that comes as time marches on, notes Janiene Luke, MD, associate professor of dermatology at Loma Linda University in California. "The skin is like a drape for the underlying musculature," she says, "so if those muscles are toned, you'll look firmer and your skin will be less baggy."

Even just a few minutes a day can make a big difference, says Kristin McGee, Health's contributing yoga and wellness editor and a yoga instructor in New York City, who put together a few of her favorite gravity-fighting poses. They're great for you anytime but are particularly key now, as we bounce back from the holidays and set ourselves up for our healthiest year yet.

1. Side Crow

This move targets bat wings. Squat with knees and feet together. Twist knees as far to the right as you can; place hands on the floor shoulder-width apart, right hand aligned with left little toe and left hand a few inches farther out. Lean forward and place upper outer left leg on upper right arm; tilt forward to lift legs, balancing them on upper right arm. Lower; repeat on the other side. Too hard.

2. Goddess Squat

This move targets saddlebags. Stand with feet about 3 feet apart, toes turned out to about 45 degrees. Bring hands together in front of chest in prayer position. Exhaling, bend knees as deeply as possible, keeping them in line with toes. Press palms together while gazing straight ahead.

3. Chair Pose

This move targets a mushy bum. Stand with feet together; inhale and lift arms overhead. Exhale and bend knees, bringing thighs toward the floor while drawing shoulder blades down and reaching arms past ears. Keep lower back long and lift through chest as you lower legs a little more toward the floor, gazing forward and keeping arms parallel. Rise to stand. Do this as a continuous flow, ideally holding each pose for 5 to 8 breaths; repeat the flow 2 or 3 times. Complete the sequence 3 or 4 times a week and in a couple of weeks you'll start to see your parts perking up.

4. Incline Plank

This move strengthens the backs of your thighs. Sit on the floor with legs extended straight out, feet together, palms at sides a few inches behind you with fingers pointing toward body. Lift hips, pushing through heels and hands, forming a straight line from head to heels. To release, lower hips back down to the floor. To make it harder, lift one leg and point toes.

5. Chaturanga

This move targets your breasts. Begin in a straight-arm plank with hands directly below shoulders and legs extended straight out behind you. Slowly bend elbows, lowering body until you're hovering a few inches off the floor; keep back flat, elbows close to sides and head in line with body. Push through palms to return to starting plank position.

6. Fish Pose

This move targets a turkey neck. Lie faceup with legs extended, arms at sides, palms down. Press forearms and elbows into the floor, lifting chest and arching upper back slightly. Continue arching back, lifting shoulder blades off the floor; tilt head back so top of head touches the floor. Continue pressing through forearms and out through heels. To release, tuck chin as you lower back to the floor.

7. Bow Pose

This move targets a rounded back. Lie facedown with legs extended, hands at sides. Bend knees, bringing heels toward glutes; grasp ankles with hands. On an inhale, lift heels while bringing thighs and chest off the floor. Look forward, breathing evenly. To release, exhale and lower thighs and chest to the floor, letting go of feet.