Beat the summer heat and feel the burn of a good workout by taking a dip to get fit -- in the pool!

Aquatic exercises have several advantages over dry-land workouts. Because your weight in water is a fraction of what it would be on land, it's low-impact and kind on your joints and muscles while it tones you all over. Plus, water gives 12 times more resistance than air, so you can burn more calories.

Best of all, you don't even have to know how to swim to reap these benefits. Here are some moves to get you started -- do each exercise for one to three minutes before moving to the next; repeat for a total of 20-30 minutes.

Water treading

Works your heart and lungs, and burns more calories

1. Stand in chest- to shoulder-deep water, knees slightly bent.
2. Jump up and tread vigorously.

Aqua lunges

Shape thighs the joint-friendly way

1. In waist-deep water, stand with hands by your sides.
2. Quickly jump up and lunge with your right foot forward, both arms swinging up in front of your chest, palms facing up.
3. Jump up and return to starting position. Repeat, alternating legs.

Cross arms

Strengthen your chest and upper back

1. Stand straight in shoulder-deep water, with your arms out to your sides parallel to the pool floor, elbows slightly behind you, palms flat and facing forward.
2. Keeping torso straight, bring arms together in front of your chest, crossing over at the wrists. Push arms back to starting position and repeat.

Bicep curls

Tone your arms in a snap

1. Stand straight in shoulder-deep water, hands by your sides.
2. Keeping your elbows still, raise your forearms to your chest, palms facing up. (For maximum resistance, open fingers into a claw as you move.)
3. Turn palms down and lower forearms to starting position. Repeat.

Water running

Strengthen lower back and abs, and firm legs by "jogging" in the water

1. Stand in ribcage-deep water, then "jog" forward as quickly as you can using a heel-to-toe motion.
2. Repeat backward.