Water Workout.

A fun way to stay fit

Exercising in the water is a good choice any time of the year. Whether you swim laps, run in water, or perform aqua aerobic exercises, the fitness value of water exercise is superb. It conditions the heart, lungs, and all major muscle groups, building muscle endurance and strength, as well as cardiorespiratory endurance. Best of all, since 90 percent of your body is supported by water, there is a very small injury risk because there is little stress on joints and ligaments. Water exercise is probably the best choice for those who are overweight and out of shape, and for those who have arthritis or knee or lower-back problems.

Longer or Harder?

Calories burned while swimming or exercising in water are less than those burned while using your treadmill, but they add up. Swimming a slow crawl for a half hour burns about 260 calories, while the treadmill uses about 350. A stationary bike burns about 250 calories per half hour. A faster swimmer or more intense pace of aqua exercise will burn more calories than a lesser effort, but a slower swimmer or exerciser will burn more by going longer. Initially you need to focus on either intensity or time, not both.

Finding a Pool

The United States has more than 2.5 million public and private pools. Looking for a facility near you? Call your nearest YMCA or health club for information. You can also check with a motel or hotel in your area. Some feature pool memberships for exercise in the water.

Look for a water temperature between 82 and 85 degrees. Water that is too warm can make you feel weak, while cold water can cause pain in stiff or arthritic joints. If you fear the water, wear a flotation device and stay in the shallow end of the pool or near the side. Your options for exercise are still many.

Different Strokes

For calorie burning, strokes matter. A 123-pound woman doing the sidestroke will burn 68 calories in 10 minutes, while a 170-pound man will burn 90. That same woman burns 95 with a slow crawl or backstroke; the man, 130. The breaststroke eats up about 91 calories during a 10-minute swim for the woman, 125 for the man. If you are a reasonably good swimmer but out of shape, start with one lap of the pool; then rest a minute. Do this for 10 to 20 minutes. During successive sessions, gradually increase the number of laps and decrease the rest periods. A good cardiorespiratory workout in the pool should last 20 minutes or longer, with a five-minute warm-up and cooldown added to that.

I Can't Swim

People who aren't swimmers can still do a variety of water exercises, including aqua aerobics, walking, or jogging across a pool in chest-deep water, or running in place while treading water in the deep end of a pool. Use a flotation device to stay upright in the deep end and lift your knees high; pump the arms back and forth. Devices such as fins, hand paddles, and inflatable rubber mitts help strengthen your upper body or legs by increasing resistance against the water.

The best way to learn some good water exercises is to take a class at your local Y or health club. A total body workout in the water should include exercises for all major muscle groups. A typical warm-up and cooldown can include shallow water walking with gentle arm movements back and forth. A combination of leg kicks and leg lifts can work the lower body, while arm circles and figure eights work the upper body, including shoulders, chest, and back. Running in water or bouncing up and down off the bottom are also good conditioning moves. Kicking laps across the pool holding on to a kickboard is a great conditioner, and can be done by nonswimmers. Have fun!

Sherry B. Hanson writes on health topics from Brunswick, Maine.