Slide show: Aquatic exercise how to's

Aquatic exercise is a low-impact activity that takes the pressure off your bones, joints and muscles. Water offers natural resistance, which helps strengthen your muscles. You can even do aquatic exercise if you don't know how to swim.

You might start with water walking. In water that's about waist-high, walk across the pool swinging your arms like you do when walking on land. Avoid walking on your tiptoes, and keep your back straight. Tighten your abdominal muscles to avoid leaning too far forward or to the side.

To increase resistance as your hands and arms move through the water, wear hand webs or other resistance devices. Water shoes can help you maintain traction on the bottom of the pool.

Once you're comfortable walking in waist-high water, try walking in deeper water. As you walk, swing your arms. Keep your back straight, and tighten your abdominal muscles to avoid leaning too far forward or to the side.

To help you stay above the water, you might place a water noodle between your legs. Make sure the noodle is higher in back than in front. If you don't know how to swim, wear a flotation vest or float belt in deep water. To increase resistance as your hands and arms move through the water, wear hand webs. Water shoes can help you maintain traction on the bottom of the pool.

For a more intense workout, consider jogging in deep water.

Hand webs can help you strengthen your biceps and triceps in the water. Wearing hand webs, stand in waist-high water with your arms down, your palms facing forward and your elbows close to your body. Raise your forearms to the level of the water, keeping your elbows close to your body and your wrists straight. Then switch direction and push your hands down until your arms are straight again. Repeat 12 to 15 times or until you're fatigued.

Water weights are foam barbells that create resistance under water. Start with your arms at your sides. Grip the bars of the water weights with your palms facing up. Raise your forearms to the level of the water, keeping your elbows close to your body and your wrists straight. Then turn the barbells over so that the palms of your hands face the bottom of the pool. Push your hands down until your arms are straight again. Repeat 12 to 15 times or until you're fatigued.

Kickboards provide another type of resistance. Standing up straight with your legs comfortably apart, tighten your abdominal muscles. Extend your right arm and hold the kickboard on each end. Keeping your left elbow close to your body, move the kickboard toward the center of your body. Return to the starting position and repeat 12 to 15 times or until you're fatigued. Then extend your left arm and repeat the exercise on the other side.

To strengthen your leg muscles, tie a water noodle into a knot around your foot or water shoe. Stand with your back to the side of the pool in waist-high water, placing your arms on the edge of the pool for stability. Straighten your leg in front of you, then flex your knee to about a 90-degree position. Return to the starting position and repeat 12 to 15 times or until you're fatigued. Tie the water noodle into a knot around your other foot or water shoe and repeat with the other leg.

Aquatic exercise can be fun at any age, size or fitness level — whether you try it on your own or sign up for a class. Jump in. The water's fine!