WHEN THE LATEST REPORT ON THE LINK between exercise and good health was published in mid-April, you could practically hear spandex snapping and sneakers being laced. A 26-year study of 17,321 Harvard University alumni by Harvard and Stanford researchers found that “vigorous” activity—defined as activity that burns at lease 1,500 calories a week—lowered their risk of dying by 25 percent. A lower risk of dying? Athletes everywhere high-fived each other. Scientists and physicians sniffed, “We told you so.” The media went into overdrive: The study’s findings were reported on most TV newscasts and made the front page of the New York Times and major Texas newspapers.
About the only person who wasn’t impressed by the study, it seems, was Kenneth Cooper, the Dallas physician who is the nation’s most famous fitness expert. For the past year, the 64-year-old Cooper has been arguing the opposite of what the new study suggests: Vigorous exercise, he contends, is bad for you. In truth, his beef is partly semantic: While the new study describes 45 minutes of brisk walking five times a week as vigorous exercise, Cooper says, “That’s not what I call vigorous.” Such exercise, he insists, is moderate, and he agrees that moderate exercise can be good for you—but only up to a point. Kenneth Cooper believes too much exercise of any kind is dangerous and potentially life-threatening.
The news that exercise may be deadly is shocking enough, but what’s even more shocking is that it’s being delivered by Cooper, the guy who got America exercising in the first place. It was Aerobics, Cooper’s 1968 best-seller, that made the earliest case for getting in shape: “Vigorous activity,” he wrote, “has more and more proved worthwhile both as preventive medicine and as a cure.” In the book’s appendix, Cooper published a slew of charts detailing how a person could achieve the target level of exertion by following his system of aerobics (a word he coined from the adjective “aerobic” meaning “occurring only in the presence of oxygen”). Points were tabulated on the basis of completed distance. A round of golf (“No motorized carts!”) earned you three points, the same as running a mile; running a mile five times got you fifteen points. The weekly ideal, Cooper asserted, was thirty points.
The book was revolutionary, shaking up the sedentary sixties. Before its release only 100,000 eccentrics called themselves joggers, but by late 1968, the nation’s trails were overflowing, and now more than 34 million people run regularly. Also in 1968, heart attack rates peaked and then began to drop steadily. And Aerobics brought instant fame to the unassuming cooper—here and around the world. (To this day, Brazilians call aerobic workouts “Coopering.”) Among other things, its success allowed him in 1970 to open the Cooper clinic and the Cooper Clinic and the Cooper Institute for Aerobics Research. At the complex, which sits on 32 acres on Preston Road, a team of specialists consults with the nearly five thousand patients who come to the clinic each year and pay up to $1,200 for stress and fitness tests, complete physicals, nutritional analyses, psychological workups, and the like. Not surprisingly, many of Cooper’s patients are celebrities in their own right: Ross Perot, Roger Staubach, Tom Landry, Linda Gray, Susan Howard, and even Governor George W. Bush, who often jogged on the clinic’s well-manicured course before moving to Austin.
Yet while the arc of Cooper success has been consistent for nearly three decades, his thinking has not. He began to have doubts about the benefits of exercise in 1984, when his 52-year-old friend Jim Fixx, the author of The Complete Book of Running, dropped dead of a heart attack while jogging. For the next few years, Cooper fixated on Fixx, trying to understand whether his death had anything to do with his sixty-mile-a-week running habit. Eventually, unwilling to concede the dangers of exercise, Cooper wrote a book, Running Without Fear, that linked Fixx’s death to hereditary factors.
Then similar stories began to drift in. There was the woman who spent ten hours a day teaching aerobics until she developed a melanoma on her jaw and was dead within the year. There was the super-athlete, a winner of Ironman competitions, who a deadly melanoma. There were the elite athletes who trained to exhaustion and came down with terminal illnesses: Fred Lebow, the founder of the New York City marathon—dead of a brain tumor; running guru George Sheehan—dead of prostate cancer; master marathoner Werner Tersago—dead of a brain tumor; world record holder Sy Mah, who had run 524 marathons—dead of cancer; Steve Scott, the first American to break a four-minute mile one hundred times—battling testicular cancer; marathoner Mark Conover, winter of the 1988 Olympic trials—now fighting Hodgkin’s disease; and Olympic runner Marty Liquori—now in the advanced stages of leukemia. Today Cooper claims to know of 150 such cases, including 94 athletes with prostate cancer who are patients at his clinic. The anecdotal evidence, he says, is overwhelming. Too much exercise can kill you.
IN HIS SPACIOUS WOOD PANELED OFFICE ON THE clinic grounds, Kenneth Cooper likes to barrage visitors with charts and statistics and endless talk about the science of good health. Seated behind his desk, he does his best to stay calm; and much of the time he has the serious demeanor of someone consumed with living his life right. But often he bounds out of his chair to take a phone call or greet a patient, and he habitually rises up and down on his toes, as if he can’t wait to break into a sprint. For a man near retirement age, he has an unusually athletic frame and impressive energy. Just as he cares for his patients’ well-being, he clearly cares for his own.
And just as he is direct with his patients when diagnosing what ails them, he is refreshingly matter-of-fact when he explains his shift in thinking. “At the time, I knew scientific evidence had established that regular exercise was essential to good health and