Like his father and grandfather before him, the typical American man of the 21st century works for his living. In most cases, though, he works with his mind, not his body.
It wasn't always that way. As recently as the 19th century, 30% of all the energy used in the American workplace was provided by human muscle power; today, the percentage is minuscule. In most ways, the transition from an agricultural economy to an industrial society to today's information age has been a great boon. But something has also been lost.
Technology has freed men from physical labor both at work and at home. In addition, unprecedented efficiency, productivity, and affluence have produced shorter workdays, more vacation time, and earlier retirement. It all adds up to more free time for most men.
What did you do with your free time this week — and does it matter to your health?
The national pastime
America has become a nation of spectators. The latest statistics from the National Centers for Disease Control and Prevention (CDC) tell the tale: 29% of adults are entirely sedentary and another 46% don't get enough physical activity. That means only a quarter of all Americans get the exercise they need.
The real situation may be even worse. Most people who say they exercise report walking as their only regular physical activity, but when researchers from the CDC evaluated more than 1,500 people who said they were walkers, they found that only 6% walked often enough, far enough, or briskly enough to meet the current standards for health. Even people who report intense activity often overstate their efforts. Scientists from the University of Florida asked people to keep a log of their physical activities for a full week while they were hooked up to ambulatory heart monitors. Some 47% of the subjects reported that they had engaged in moderate activity, but only 15% actually boosted their heart rates enough to sustain moderate activity. The gap was just as great for more intense exercise: 11% reported hard activity, but only 1.5% boosted their heart rates to that level. Nobody achieved a heart rate consistent with very hard activity, though 1.5% made that claim.
"Spectator" is a kind word for it; in fact, we are a nation of couch potatoes.
If Americans are not physically active on the job or off, what are we doing? Just look around you. Work usually means sitting behind a desk, in front of a computer, or behind a steering wheel. Free time involves more sitting, often at the kitchen table or in front of a TV. The most obvious consequence is the steady growth of America's waistline; more than half of all men are overweight or obese. Type 2 diabetes (formerly called adult onset diabetes) is another result, and the number of cases is increasing steadily.
When researchers at Harvard studied 37,918 men between the ages of 40 and 75, they found a strong link between the amount of time a man spent watching TV and his risk of diabetes. None of the men had diabetes when the study began in 1986, but over the next 10 years the men who watched the most TV were nearly three times more likely to develop the disease than those who spent the least time in front of the tube. TV watching has also been linked to obesity, another diabetes risk factor — but even when the scientists took obesity into account, they found that heavy-duty TV watching increased the risk of diabetes by nearly two and a half times. And another Harvard study found that men who watch the most TV have higher levels of LDL ("bad") cholesterol and lower levels of HDL ("good") cholesterol than those who watch less. Along with diabetes and obesity, it's an invitation to cardiovascular disease — and tuning into medical shows like ER won't lessen the risk at all.
The average American man spends more than 4 hours a day watching TV. If he devoted just 30 minutes of that time to exercise, he'd be much healthier.
Regular exercise has enormous benefits. In addition to reducing the risk of obesity and diabetes, it lowers blood pressure and cholesterol levels. The net result is a lower likelihood of heart disease and stroke, the first and third leading causes of death in the United States.
Physically active men also have a reduced risk of colon cancer, and they may get some protection against prostate cancer as well. Exercise will help men preserve their muscles and bones as they age; resistance exercise does this best. Exercise also fights depression and anxiety and promotes healthy sleep, improving the quality of daily life.
And if all these benefits don't convince you to get off your duff, consider a Harvard study that found men who invest 30 minutes a day in exercise are 40% less likely to develop erectile dysfunction than sedentary men.
Physical activity can help men enjoy longer and more vigorous lives — but do you have to become a gym rat or jock to earn the benefits of exercise? Not at all.
In fact, men who use even a modest fraction of their free time for physically active pursuits will reap the gains of exercise without the pain of competitive sports, much less the strain of physical labor at work.
Many studies from around the world confirm the benefits of leisure time exercise. Here are some examples.
Golf. It's a prime illustration of the best and worst of modern American leisure. It keeps millions glued to their easy chairs, watching televised tournaments every weekend. It also gets millions out of the house to enjoy the pleasure of fresh air and the challenge and camaraderie of golfing. Companionship and challenge are great — but the ubiquitous golf cart deprives many players of the health benefit of walking the course. Golfers who do walk may be in the minority, but they are the true winners, no matter how many strokes they take.
A study of 110 men who were healthy but sedentary shows how golfers can score. Half the men were randomly chosen to play two to three 18-hole rounds of golf a week, always on foot, while the others remained inactive. In just 20 weeks, the golfers lost about 3 pounds and nearly an inch from their waists; even more important, they cut their average LDL cholesterol by 12% and their triglycerides by 14% while boosting their HDL by 5%. And these gains were achieved with virtually no pain or injury. All it took was an average of 2½ rounds a week — or, for nongolfers, about 12 miles of walking each week.
Gardening. Men who don't like to putt may still enjoy puttering in the garden — and they'll also enjoy the results. For example, a study of adults in King County, Wash., found that people who gardened regularly were 68% less likely to die from cardiac arrest than sedentary people. And you don't have to dig from dawn to dusk to get the protection; in fact, anything over an hour a week produced real gains.
Biking. Riding a bike can be just as good as gardening. In a study of more than 800 older men in the Netherlands, regular biking was linked to a 29% reduction in the death rate. (And the study reported similar benefits for gardening, even with just an hour of yard work a week.)
Walking. Because it's the dominant form of exercise, it has attracted the most attention from researchers. Studies from around the world agree that a little walking can go a long way toward keeping you healthy. Here are some typical results:
- A 12-year study of 707 retired men in Hawaii found that the death rate of men who walked at least 2 miles a day was more than 50% lower than that of men who walked less than a mile a day.
- A study of Harvard alumni found that men who walked more than 7 miles a week had a 33% lower death rate than sedentary men. Walking up stairs was nearly as good; men who averaged about 8 flights a day reduced their death rate by 25%.
- A 4-year study of 1,645 men and women over 65 found that people who walked at least 4 hours a week enjoyed a 31% lower risk of death than those who walked less than an hour a week.
- A Harvard study of 72,488 female nurses found that walking for 3 hours a week reduced the risk of heart attacks by a third, or exactly as much as 1½ hours of intense exercise. And a companion study of 61,200 nurses linked regular walking to a 55% reduction in the risk of hip fractures.
- A Harvard study of 39,372 professional women found that walking for just an hour a week cut the risk of heart attack by half. Women who increased their weekly mileage enjoyed additional benefits, but women who accelerated their pace did not.
Most studies evaluate overall activity instead of rating individual forms of exercise. Here are some results:
- A 10-year study of more than 5,200 adults found that exercising reduces the risk of gaining significant amounts of weight by nearly two-thirds.
- A Danish study of 30,228 men and women found that people who invested at least 2 hours in exercise each week enjoy a 28% lower risk of hip fracture than sedentary people.
- A Canadian study of 9,008 men and women and an American study of 5,925 women over age 65 agreed that physical activity is linked to a reduced risk of cognitive decline and dementia in old age.
- A study of 4,485 middle-aged men linked exercise that continued after the age of 40 to a 31% reduction in the risk of stroke.
- A study of 1,453 men between 42 and 60 found that 2.2 hours of leisure time exercise each week reduces the risk of heart attack by 69%.
- A study of 1,072 men between age 35 and 63 reported that sedentary men are nearly three times more likely to die during the 10-year observation period than those who exercise.
- A study of 500 men and women linked leisure time exercise, but not workplace activity, to reduced atherosclerosis in the carotid arteries, which supply blood to the brain.
- Two 2003 European studies found that moderate to high levels of activity are associated with reduced levels of C-reactive protein and other markers of inflammation and atherosclerosis.
It's an impressive list, but it doesn't do justice to the even larger body of evidence that shows how much regular physical activity can do for you, even if it's modest exercise. Think it over, then move toward health.
What to do
The first step is to take a good look at your free time. Be sure that you actually have enough discretionary time. For health as well as pleasure, it's important to balance work and play, tasks and leisure. If your schedule is too full, modify it to restore balance and flexibility.
Next, look at your health. Most people can exercise without special precautions, but men with heart disease, diabetes, severe arthritis, or other important problems should check with their doctors. A stress test is rarely necessary unless your doctor is worried about your heart.
It's also important to take stock of your personal experience and preferences. If you've never played golf or ridden a bike, either would be a poor choice; if there's no pool in your neighborhood, swimming might pose logistical hurdles that could send you diving for your couch. Decide if you want a solitary activity or a shared experience. Best of all, try to plan a variety of things that you can do as the seasons change or when you travel.
For most men, walking really is an ideal first step: It's easy and natural, it's portable, it doesn't require special equipment or facilities, and it rarely leads to significant injuries. You can walk indoors or out, alone or with a companion.
How much time should you devote to a physically active pastime? Thirty minutes a day is an excellent target, as long as your exercise is reasonably brisk and you do it nearly every day. Walkers, for example, should aim to cover about 2 miles a day; it takes a brisk clip to get that done in 30 minutes, but if you are more comfortable walking at a gentler pace, give yourself 45 minutes to cover your distance. Remember, too, that you can divide your exercise into two 15-minute or three 10-minute segments instead of doing 30 minutes all at one time.
Every little bit of exercise helps, but there is a risk of overestimating the contribution of small amounts of exercise. Your goal should be to burn at least 150 calories a day with exercise; the table Ways to burn about 150 calories lists some ways to meet that goal.
As your capacity improves, you may choose to devote even more time to physically active pursuits. It would be an excellent choice; the first 150 calories a day are the most important, but you can get additional health benefits — and fun — from twice that amount. And while recreational exercise is the most enjoyable way to move for health, you can — and should — extend the principle to daily life, too. Take the stairs, especially going up; if your capacity is modest and your destination high, walk a flight or two, then switch to the elevator. Mow your lawn by hand or wash your car yourself. Walk to the store when you can. It wouldn't even hurt to help with the housework.
Listen to your body. Exercise often produces aches and pains, but they are usually minor ailments that you can treat yourself. But if your problems are severe or persistent, back off and get help.
Listen to your mind, too. It's your free time, and it should be enjoyable. Exercise is the means to an end — good health — but it should also become an end on its own — pleasure. Keep experimenting until you find rewarding, enriching ways to fill your exercise prescription.
Listen to all the scientists who say that physical activity will improve your health. Or listen to what Edward Stanley, the earl of Derby, wrote in 1873: "Those who think they have not time for bodily exercise will sooner or later have to find time for illness."
Finally, it's time to stop listening and start moving. Use some of your free time to enhance your health, even if it means turning off the TV. In fact, you can take the first step toward better health by turning it off without using the remote.
(This article was first printed in the May 2004 issue of the Harvard Men's Health Watch. For more information or to order, please go to www.health.harvard.edu/mens.)