04.08.12

Swimming to Health? Excerpt of Lynn Sherr’s ‘Swim: Why We Love the Water’

In her new book, Swim: Why We Love the Water, Lynn Sherr reports that the benefits of regular swimming extend even to your mental health.

Henry James, as usual, said it best: the two most beautiful words in the English language are “summer afternoon.” Add the word “swimming,” and the day blooms even more grandly. We’re not there yet, but with the balm of spring warming the air, it’s time to suck in your stomach and get ready for the water. And that’s just the beginning of all the good things swimming does for your body.

It both soothes and energizes, the best full-body massage available. I think that’s partly biological: the skin is our largest organ, so swimming is our most sensuous sport. Little wonder poet Paul Valéry described the sea as his lover: “In it, I am the man I want to be.”

If your idea of perfection is less about soggy sex than staying in shape, swimming is still your best choice: a rhythmic, dynamic activity that uses every large muscle group. It helps build lean muscle mass and promote flexibility. And while all aerobic exercise leads to many of these results, one recent study shows that swimmers bested joggers and walkers in every cardio number. More significant for a nation with an aging population, you don’t hear complaints about bone spurs in the pool. “Swimming is the closest thing on this earth to a perfect sport,” writes Dr. Jane Katz, a pioneering swim fitness promoter and educator. Movie star Esther Williams adds flatly, “Swimming is the only thing you can do from your first bath to your last without hurting yourself. When you’re in the water, you’re weightless and ageless.” No knees pounding the pavement. No joints slamming against a ball or a wall. Buoyancy protects the most vulnerable parts of our skeleton. Just ask a pregnant woman. “Suddenly that big bump becomes weightless,” rhapsodizes a young mother recalling her blissful Caribbean swims at five months along.

For people with certain disabilities, swimming feels like a miracle. The poet George Gordon, better known as Lord Byron, was born with a club foot, a contracted Achilles tendon that gave him a pronounced and debilitating limp. In the water, he moved like an eel. Annette Kellerman, the Australian swimming champion and American silent-film star, wore heavy iron braces on her legs as a child, the result of a bone ailment. Swimming lessons turned her into a mermaid.

In the millennia since swimming has been embedded in our culture, astounding claims have been made for its benefits. A Renaissance writer claimed that it purged “poisoned humors, drying away contagious diseases.” A 19th-century French physician said it cured masturbation. A 1910 YMCA manual promised that swimming outdoors “prevents the growth of gray hair.” If only. Swimmers are hale, not disease-proof; hardy, not ageless. But there are alluring indications that regular, vigorous water activity may indeed extend human life. Every time we grind out our laps, we may, in some measure, be swimming in the fountain of youth. The proven benefits read like a wish list from the American Heart Association: swimming can lower blood pressure and optimize cholesterol levels, improve the pumping capacity of the heart and thus enhance circulation, expand the ventilator capacity of the lungs and thus enhance cardiovascular performance. One celebrated study found that mortality rates for swimmers were lower than for those who are sedentary, walkers, and runners.

Alas, this otherwise ideal sport may not do much for our waistlines. While swimming can smooth out the figure and certainly burn fat, it does not directly promote weight loss. According to Dr. Joel Stager, associate director of Indiana University’s Department of Kinesiology, that’s because “losing weight is about efficiency—the amount of work done divided by the metabolic cost of doing that work.” The problem, he tells me, “is that most people who need to lose weight are so out of shape, they can’t swim far enough to make a difference. And the better swimmer you are, the less metabolic work you’re doing. So as you become more efficient, if you’re swimming to lose weight, you are defeating your purpose by getting better.” Blame it, he says, on buoyancy, which “reduces the energy expenditure associated with swimming.” It’s a dilemma, but not one that troubles Dr. Stager. Weight, he points out, is not a good index, especially since muscle mass weighs more than fat.

Dr. Stager, who is also director of IU’s Counsilman Center for the Science of Swimming, is a principal investigator of an ambitious study on the health effects of swimming on the human body that may change our understanding of the central nervous system. “Our hypothesis is that maintenance of physical activity—specifically swimming—preserves higher brain activity,” he says. His project, in conjunction with the IU Brain Science Lab, focuses on the hard-swimming members of U.S. Masters Swimming: men and women who swim 3,500 to 5,000 yards (that’s two to three miles) three to five times a week. Some have been doing it for nearly 20 years. “There are,” Stager says, “few comparable populations who engage in routine intensive daily exercise for decades.”

“We’ve found that the arteries of older USMS members tend to be more elastic than those of younger nonswimmers,” Dr. Stager tells me. “And that the muscle mass of older Masters Swimmers is equivalent to [that in] persons 15 years younger. Masters Swimmers have lower average heart rates than sedentary controls. That’s good. But it also appears to be good for your brain.” Among the findings so far: Active swimmers appear to have greater cell density and “connectedness” in the cerebellum, which could mean protection from age-related complications in gait and balance that lead to falls. And they show very little decline in nerve conduction velocity (NCV)—the speed with which your brain tells your muscles what to do: the NCV rate in 80-year-old swimmers was similar to that of 50-year-olds in the general population. Smaller age-related declines have also been found in Masters Swimmers’ working memory capacity, which is reflected in decision making and reaction time in making decisions. I ask if he believes that the evidence so far is incontrovertible that swimming slows down the aging process.

No knees pounding the pavement. No joints slamming against a ball or a wall. Buoyancy protects the most vulnerable parts of our skeleton.
swim-why-we-love-the-water
‘Why We Love the Water’ by Lynn Sherr. PublicAffairs, 232 pp. $17.15 ()

“Yes,” Dr. Stager says, “but we have to be careful with the terminology. Maybe typical lifestyles—sedentary lifestyles—accelerate what we commonly think of as aging. What we’re really trying to do is separate sedentarism from aging. So what we’re saying is, the Masters Swimmers—and this is a flip—demonstrate what is necessarily aging. What the general population is demonstrating is sedentarism.”

In other words, maybe Masters Swimmers are the norm; they’re how we should all look. And they are aging less quickly than the rest of the population. “Absolutely,” he says. “What we used to think was a necessary consequence of aging now appears to be more related to lifestyle choices. This is really important.”

It is a striking preliminary conclusion for a work still in progress. Swimming, unlike most addictions, is actually good for us, perhaps even better than we thought. And the more we swim, the bigger the benefits. Including mentally.

“If I go in like a cranky sea lion, I come out like a smiling dolphin,” said California endurance swimmer Carol Sing in 1999, after she became the then-oldest woman (at 57) to swim the English Channel. That was two years after she became the oldest woman to cross California’s Catalina Channel. As I said, it’s about lots more than trimming your gut. So, should you dive in?  Consider the poetry of Dr. Edward Baynard, from 1764:

Of exercises, swimming’s best,
Strengthens the muscles and the chest,
And all their fleshy parts confirms.
Extends, and stretches legs and arms,
And, with a nimble retro-spring,
Contracts, and brings them back again.
As ’tis the best, so ’tis the sum
Of exercises all in one,
And of all motions most compleat,
Because ’tis vi’lent without heat.