Fitness After 50: The Gym Goes Gray (cont.)

Milner agrees: "A lot of the problems we used to think of as being related to aging, we now know aren't related to aging at all. They are related to disuse of the body, and boomers have finally begun to realize 'Hey, we can do something about that.'"

Indeed, studies continue to show that we can. For example, research recently published in the Journal of the American Geriatric Society found that inactivity doubles the risk of mobility limitations as we age, while vigorous activity has the opposite effect. In another study, published in the journal Neurology, doctors found that exercise can slow cognitive declines -- meaning our minds can stay sharper longer.

"No matter what area you look to, be it heart disease, obesity, diabetes, high blood pressure, osteoporosis, research shows that being physically fit into your senior years will keep you healthier and active longer," says Cedric Bryant, PhD, chief exercise physiologist at the American Council on Exercise.

And baby boomers are not about to let that opportunity slip by, experts say.

"Unlike our grandparents, who simply hoped they could hang around long enough to collect Social Security, our generation has every expectation that at 60 we're going to be doing the same things we did at 45 -- and it's a very good possibility that we will," says Witherspoon.

Redefining Fitness, Boomer-Style

While the idea of midlife fitness may have been sneaking into our collective consciousness for some time, experts say the real difference came when health clubs themselves began to change.

Leading the pack: a Harlington, Texas, company with a chain of health clubs known as Curves. It started in 1995 as one location offering a circuit-training program aimed at women over 45, and in just 36 months it grew to 1,000 locations. Today there are some 9,000 Curves gyms worldwide.

But what was different about this club? Some believe it simply made fitness easier for the overworked, overstressed Boomer to achieve.

"It put the health club into the neighborhood, and created a fast, time-saving, 30-minute workout a woman could easily fit into her day," says Milner.

It also did something else. Experts say it created a more attainable model for success.

"Essentially, it did away with the 'perfect body' dream, and replaced it with the much more realistic 'better lifestyle and better health' dream -- and it worked," says Milner.

It also helped spawn an entire industry. In addition to the 8,000 Curves locations around the United States, similar organizations such as Slim and Tone for women and now Cuts -- a kind of Curves for men -- are taking off.

What's more, even gyms and health clubs that have traditionally courted the hard-body set are looking to catch some backsplash from the Baby Boomer fitness wave. Bally Total Fitness is launching an ad campaign aimed at Boomers, according to news reports, while the Southern California chain of Gold's Gyms plans to begin featuring 50-somethings in its ads.

50-and-Up Fitness: What You Must Know