Results of a 30-year study find that you can turn back the clock on aging by starting a moderate but consistent exercise program. Even if it's been years since you saw the gym, exercise can restore aerobic capacity to levels attained as a young adult, experts report.
A two-part follow-up study at the University of Texas Southwestern Medical Center in Dallas tracked five healthy men over three decades in one of the most intensive fitness studies ever attempted.
It began in 1966, with five fit 20-year-old college students. The study, which sought to determine the adverse effects of bed rest on physical fitness, put its subjects to the ultimate test: three weeks of bed rest.
The men were confined to total and complete inactivity, ordered to use a wheelchair even for trips to the bathroom.
The effects were remarkable. Results showed that the men's hearts had actually become smaller. Furthermore, the men's muscles had shrunk, causing a 25 percent reduction in strength and stamina.
Dr. Benjamin Levine from the Presbyterian Hospital in Dallas told World News Tonight correspondent John McKenzie that the results of the study were significant.
"These 20-year-old men, after three weeks of bed rest, now had the physical fitness of men that were 45 or 50 years old."
Exercise can reverse the effects of aging
Thirty years later, researchers brought those same five men back together again, for one more experiment, this time to see if they could actually reverse some of the effects of aging through exercise.
The men, now overweight and out of shape and in their 50s, were put on a six-month exercise program. To begin, they were asked to exercise just 40 minutes a week, be it walking, jogging, or cycling.
For those unaccustomed to any sort of exercise, the task was not so simple.
"I had a hard time running a mile," says Kazmer Laszlo, a volunteer from the study that spoke with McKenzie.
Gradually the workouts increased until each man was exercising at least five hours a week, an exercise program even Laszlo agreed was "relatively comfortable and routine."
The five were then put through a new series of fitness tests. The results were dramatic. In just six months, "we got them back to where their physical work capacity was virtually identical to what it was when they were healthy, vigorous 20-year-olds, " Levine said.
It's never too late to exercise
The most important take-home message suggested by the findings is that it's never too late to start exercise training. In fact, the older people become, the more they need regular exercise.
Experts say working out combats the frailty of old age. And it helps prevent bone loss, increase muscle strength, and improves balance and coordination, which in turn help reduce the risk of falls and fractures.
Exercise is also known to reduce the risk of dozens of disease associated with aging and increases the ability for basic living.
Dr. Reed Humphrey, associate professor of physical therapy and physiology at Virginia Commonwealth University in Richmond, Va., further explains that, with age, an individual's heart rate naturally declines, making it more difficult to pump oxygen to the muscles. This is why it can be so exhausting for an older person to carry in the groceries or get up from the couch.
Exercise, however, boosts heart rate, which, in turn, increases oxygen flow to the muscles. The ability of the muscles to use this oxygen is not affected by age. Once the oxygen arrives, the muscles will respond as they did years ago.
In this way, "exercise capacity can be substantially restored at any age to at least healthy levels and probably beyond," Humphrey says.
"Even among the most sedentary of people, starting exercise shows great gains. It doesn't matter when you start, you will inevitably see a benefit," agrees Dr. Neica Goldberg, a spokesperson for the American Heart Association and chief of cardiology at Lenox Hill Hospital in New York City.
An excuse to be lazy?
Results of this study do not mean that those in their 20s and 30s should take solace in the fact that they can be lazy now and make up for it later.
"[That] is just dead wrong," laughs Goldberg.
"In real life, particularly in men, many individuals with poor health habits will have already developed coronary artery disease by middle age, explains Dr. Philip Ades, director of cardiac rehabilitation and preventive cardiology at the University of Vermont College of Medicine in Burlington, Vt.
"If you wait until your 50s to start a program, slothfulness will have left you overweight, hypertensive, hyperlipidemic, and unhappy."
So don't wait until your health fails and your skin sags to start working out. Humphrey reports that working out 30 minutes a day, three to four days a week, will provide substantial health benefits. Even greater benefits can be attained with more intense workouts.
There's no formula for the amount or type of exercise, say some experts it truly depends on the person. Humphrey suggests that in older patients, it is not so much the number of calories burned but the amount of exercise performed.
And Goldberg adds that it need not be Olympic exercise, but can be something as simple as gardening or chores.Get the latest wellness, nutrition and fitness information in our Health Club section