June 12, 2000 -- I've always had a so-so relationship with water. At summer camp in Maine, I remember desperately clinging to the docks until the very last moment, when my frustrated swim counselor nearly drop-kicked me into the icy lake. Summer after summer, I was grouped with the tadpoles and the guppies, never the dolphins or sharks.
So it was no surprise that as an adult I gravitated towards land-based activities like running. But about seven years ago, my back rebelled, which wreaked havoc on my 6-mile-a-day jogging habit. I couldn't imagine giving up on running. Luckily, I'd just read in a fitness magazine that working out in water was as good as doing it on land. So I slapped on my ratty old Speedo and took to the water.
Walking onto the pool deck that first day, wearing a big blue aqua running belt that would keep me buoyant in the deep water, I scanned the pool for other aqua exercisers. There were some silver-haired ladies schmoozing by the stairs and the usual lines of lap swimmers, but there were no other water runners. I slunk over to the slow lane and slipped in. As I began my soggy jog to nowhere, I felt vaguely ridiculous and overly aware of curious glances.
But after about an hour, my legs were tired, my heart was racing, and my back didn't hurt. So I kept at it. When my back finally got better, and I laced up my sneakers again, my heart and muscles felt strong, and I hadn't lost a step.
Changing the Way People See Water Exercise
Before I started this routine, I thought of aqua exercise as something that might be fine for my grandmother, but way too wimpy for me. "That's wrong," says Mary E. Sanders, MS, professor of health ecology at the University of Nevada, Reno, and creator of many aquatics programs. "While water exercise can be great for older and overweight people, it's equally good for serious -- even competitive -- athletes." What's more, if you're pressed for time, water exercise is a great way to squeeze an intense workout into a short period.
Sanders should know. Besides looking the part of someone who's discovered a terrific workout, she's done numerous studies comparing water exercise to its land-based counterparts. Time and again she's found that the wet workouts are as good or better than dry ones in terms of fat and calorie burning, cardiovascular efficiency, and endurance.
In one of her studies, walkers who water-trained for four months increased their on-land walking speeds by more than 16% and their stride lengths by 10%. And check out these numbers: a 130-pound person burns about 6 calories per minute by aerobic dancing. The same person running in deep water at an 11-minute-per-mile pace burns about 11 calories per minute.
And more and more people are diving in. Besides ordinary folks like me, world-class athletes such as Carl Lewis are into water exercise. Their pool workouts give their bodies a break between grueling land sessions, while helping to increase speed and sharpen form. "Active recovery," they call it. College runners and basketball and volleyball players also can routinely be found training in water.
The Unbearable Lightness of Water
So what makes water so great? Several things. First, its natural viscosity, or thickness, challenges your body with a constant state of resistance. To generate greater resistance you have several options: for instance, if you wear gloves or hold your fingers closed, you'll find it harder to move your hands through the water. Pushing yourself to go faster creates more resistance. Current and depth can also make your workout harder. Ever try to swim in choppy ocean waters? The deeper you go, the tougher the work.
For the injury-prone, injury-wary, or already-injured person, water is an extremely forgiving environment. During a run on land, your foot strikes the ground between 800 and 2,000 times per mile, each time at a force of up to four times your body weight, says David Brennan, aqua running expert and assistant clinical professor of physical medicine and rehabilitation at Baylor College of Medicine in Houston. Your knees, ankles, and back take the brunt of this pounding, but in water your joints and skeleton are cushioned. You can work as hard and as fast as you want, but without the impact-related problems.
Skiers, dancers, need to work on your balance? Dive in, says Sanders. The muscles you use for balance and posture are all challenged by the constant push-pull of water. Try a one-legged squat in waist-deep water, she suggests. Not hard enough? Do it with your eyes closed and try to stay balanced. Strength work, too, can be done in water, with foam dumbbells. Think about a biceps curl, says Sanders. On land, this movement only works the biceps, whereas in water, you'll also target the triceps as you fight the dumbbell's buoyancy to lower your arm.
Choosing Your Workout: Go Solo or Join a Class
You don't have to memorize a complicated routine to get a good pool workout. Most YMCAs or health clubs with pools offer some sort of aquatic exercise class nowadays, says Sanders. Some focus on endurance, some on strength, and some on moves that will help you in your specific sport.
Water walking or running, however, are both things that anyone can effectively do alone. If you're going to be running in the deep end, all you need is your own bright blue flotation belt; for walking, a pair of nonslip shoes or old tennis shoes can help you grip the bottom of the pool. (Of course, if you haven't been exercising regularly, you should get your doctor's approval before you start.) For more tips on proper water walking and running techniques, see Wet Workout Basics.).
As for me, I'm back to being a landlubber -- most of the time. But whenever my back acts up, or I need a change of pace, I'm back in the water in a flash. I've gotten my money's worth out of my big blue belt and, summer-camp indignities aside, I've made peace with the water. I think I've finally graduated from guppy to dolphin.
Elizabeth B. Krieger is an associate editor at WebMD.