How it works
Running in water, whether it is in a lake or a pool, first began in the early 1980s. Initially, athletes did it to maintain fitness during injuries, but in recent years, deep-water running has become increasingly popular as a workout on its own.
"You get a really good workout," says a swimming fitness instructor at the YMCA-Minneapolis who didn't want his name used. "The thing is that people don't realize that it is for everyone, not just runners who are injured."
In deep-water running or aquajogging, you run more or less in place in water deep enough to keep your feet from touching the bottom of the pool. A flotation/buoyancy belt keeps your head comfortably above water so you can breathe, but your arms and legs remain submerged. The goal is to keep your body afloat as you perform the running motion. Submerged in the water, you will have resistance on all sides, which forces opposing muscles to work equally.
Benefits
"It's one of those activities that really takes very little effort to begin," the instructor says. "You have to invest in a flotation belt, but that's about it." Think of it as all the good parts of running without the negative side effects like joint damage, back problems and aching knees.
But it's not easy. Because of the resistance water provides, it's a harder workout. However, there's no specific formula for figuring how out time spent running underwater equates to time spent running on land. Many runners base their workouts in water on their heart rates, which are typically lower in the pool.
Techniques
The basic deep-water running technique is similar to natural running motion. You reach out with your leading leg and pull through the water strongly and evenly. The front foot should "land" in front of the body's center of gravity with a reduced hip flexion, keeping knees slightly higher than in normal running.
The trailing leg should be actively pulled forward because of the increased resistance of the water. Remember that you are running and not swimming, so the palms of the hands should be closed or turned inward, slicing through the water, not cupping.
It's important to keep your abdominal muscles tight and your chest lifted as you mimic your land-based running motion. Your elbows should be at a 90-degree angle. As you run, your body should naturally lean slightly forward. You might want to try alternating between pointing your toes and pressing your heels down, to work your calves and hamstrings.
To help you focus on your form, wear a flotation belt. Some people run underwater without belts, but in those cases, attention shifts to staying afloat. The arms get used much more, and workouts typically can't last very long because of the exertion of the upper body. These difficulties can, of course, provide further training stimulus.
The foam belts are worn around the waist, and it takes a little time to get accustomed to them. There are two main manufacturers, Speedo and Aquajogger, which offer a variety of styles. Typically they range in price from $40 to $100. Aquajogger also makes underwater weights and shoes to increase the difficulty of the workout.
The belts, besides helping you stay afloat, help you maintain proper from by keeping you leaning forward, not backward. You can also use them to tether yourself to the side of the pool, so you can run back and forth in your workout.
Getting started
It may take some practice to get the hang of water running, but if you concentrate on your form, just as you would while running on land, you should pick it up quickly. Most people recommend you take a class as a beginner so you can learn proper form.
After that, you can pretty much do deep-water running in any pool that has the space for it. "They don't have to be a runner to get involved," says the YMCA instructor. "They will have to learn the stride that works best for them, and that's why working with a facilitator is a good idea."
Classes around the Twin Cities area can be somewhat difficult to find. Your best bet, especially during the winter months, is to contact a running club that may organize classes. They will often have a deal with a health club to use the pool space. A group aqua run gives you the camaraderie of bobbing around in a pool with other runners while enjoying a beneficial workout.