Preventing Disease

Feeling sick and tired too often?

Suffering chronic bouts with illness and infections?

Have high blood pressure? Unhealthy cholesterol readings? Diabetes? Are you stressed out?

Ready to do something about it?

Take the exercise prescription.

Okay, okay. It''s true. Yes, even men who exercise religiously get sick at times. Some bully bacteria or virulent virus pounces when their guard is down.

But, you know what? Men who exercise get sick much less often than men who do not.

They have fewer sniffles, fewer aches, pains, fevers, colds, flus, infections, heart attacks and so on.

They feel better, more vibrant. Their minds, muscles and moods all function more effectively. Stressful situations don''t faze them much. Their immune systems are stronger and more efficient.

And when they get sick, they bounce back fast.

We haven''t created a special workout for disease prevention, since most any regular exercise routine will bolster your immune system. Instead, we''ll explain how exercise affects your body''s disease-fighting tools. If you are convinced—and may we say the arguments are most persuasive—and you haven''t exercised in a long time, turn to The Inactive Man chapter on page 139 for information on how to launch a new routine.

The Exercise Prescription

In 1995, two of the nation''s preeminent health watchdog groups—the federal government''s Centers for Disease Control and Prevention (CDC) in Atlanta and the American College of Sports Medicine—issued a joint statement that gave formal endorsement to the exercise prescription. The statement formally marked a fundamental shift in the way the medical community views the role of exercise.

"They examined a persuasive body of scientific evidence and concluded that regular moderate physical activity is an important component of a healthy lifestyle—helping to prevent disease and enhance quality of life," says Jonathan Robison, Ph.D., an exercise physiologist, nutritionist and executive co-director of the Michigan Center for Preventive Medicine in Lansing.

The exercise prescription is flexible, says Dr. Robison. You don''t have to buy a stair-climber or take part in sports you don''t like. All you have to do is accumulate a minimum of 30 minutes of moderate-intensity physical activity several days per week, he says.

"Let people know that they can garden, walk the dog and so forth—they don''t have to work out on stair-climbers and stationary bikes and treadmills to be healthy," says Dr. Robison.

The CDC and American College of Sports Medicine doctors determined that just 30 minutes of exercise—even if gathered in little snippets throughout the day—is enough to make us healthier and more disease resistant if done regularly.

"For the general population, we can probably be a little less obsessive about how high our heart rates are while we exercise or how long we''re going for at a time, and focus more on just moving and having a good time and getting our breathing and heart rates up a bit," says Dr. Robison. "The recommendation for maintaining health is to accumulate 30 minutes of moderate physical activity most days of the week. All that really matters is that it''s movement and that it is burning calories. You can walk for 30 minutes three times a week, or walk for 10 minutes nine times a week and probably get similar health benefits."

This is a recommendation for general health and, for instance, should not replace rehabilitative exercise routines prescribed for men following heart attacks or other specific conditions, notes Dr. Robison.

Throughout this book we''ve emphasized that the best fitness routine mixes up lots of exercise types to make sure you achieve all three tenets of fitness: strength, endurance and flexibility. It turns out that that apparently is the best formula for disease resistance as well. "Mixing aerobic and resistance training may offer the greatest, long-term health benefits," says Dr. Robison.

But don''t overdo it, cautions Charles Swencionis, Ph.D., head of the health psychology program at Yeshiva University in New York City and co-author of The Lazy Person''s Guide to Fitness. "Exercise that is moderate will increase resistance to disease. But overdoing it to the point of exhaustion is not going to help the immune system," he says.

And, he cautions, don''t overwork the heart when exercising. We offer a formula for calculating the proper heart rate range on page 27. But, as Dr. Swencionis says, you don''t really need to count with a stopwatch in your hand. If your heart is pumping faster than usual—fast enough that you start to sweat in a few minutes—and yet not so hard that you can''t breathe comfortably or carry on a conversation, you''re in the right zone.

Why It Works

Here''s why the exercise prescription works.

* Quite simply, "exercise is what the body is designed to do," says Dr. Swencionis. "It is not designed to sit at a desk, or use a computer, or ride in a bus or drive a car. It''s made for walking around, hunting game on the plains of Africa. That''s really the kind of thing the body needs to do. When you deprive it of adequate physical activity, it develops all kinds of illnesses."

* The chemistry of the body is affected by exercise. The type and quantity of brain chemicals and hormones released changes—for the better—in a regularly exercised body. That, in turn, affects all sorts of systems. We produce more of a blood-clot dissolving substance. Our cholesterol balance changes, making our blood thinner and easier for our heart to pump. Our blood also is redder, more pumped up with fresh oxygen, bringing more life to each cell. We tax our immune system less, thus it is more prepared for a major fight. And on and on and on.

* We make energy differently, more efficiently, when we''re fit. We also tap into different fuel stores, particularly the fat stored around the belly.

* We lose weight, and that makes a difference in how our body works. "Aerobic exercise (combined with a low-fat diet) lowers high blood pressure and cholesterol and controls diabetes. Just a loss of 10 to 15 pounds can mean you can stop taking drugs for these conditions, or take much lower doses," says Dr. Swencionis.

* Aerobic exercise increases our sense of well-being, lessens tendencies toward depression and anxiety, and puts the brakes on immune-dampening reactions to stress.

Want even more compelling evidence of how exercise will help your health? Read on.

Improve Cholesterol Levels

You probably know that HDL cholesterol wears the white hat and LDL wears the black one. But it''s really not quite that simple, explains Covert Bailey, a popular fitness writer, in his book Smart Exercise.

Our bodies need cholesterol to digest fat and to manufacture male and female hormones, he says. But too high of an LDL cholesterol level is damaging. And too low of an HDL level is not good either. Physicians, says Bailey, recognize high levels of HDL cholesterol as a sign of good health.

So that''s our goal with the exercise prescription—to raise the HDL and, maybe, to lower the LDL. If you have trouble keeping track of which is which, think of H as standing for healthy, and L as standing for lousy. It''s a bit of an oversimplification, but a good memory trick.

The more unfit you are, the quicker and more dramatic improvement you will see in your cholesterol levels when you start exercising, Bailey says. That''s encouraging. People who exercise all the time have to work hard to keep improving their cholesterol counts. Out-of-shape people will see improvement if they just start walking.

Low intensity exercise won''t produce great gains in HDL levels, Bailey says, but it will quickly lower LDL levels. And, by getting into the habit of shaking your booty, you may find it easier to make the transition to more vigorous exercise—which will raise your HDL, he says.

Lessen Stress Damage

Our bodies are equipped to snap into emergency supercharged mode in an instant in response to stressful situations. Glucose stores are released from the liver, the heart pumps faster, blood vessels to the muscles open wide, as do our pupils—so we can get a better look at what we''re confronting or the path on which we''re fleeing, notes Dr. Robison. Amino acids are sucked from tissues and burned for fuel.

All this is in response to hormones—like adrenaline—that spurt in response to stress, says Dr. Robison. In an emergency situation, the physical changes give us a tremendous edge. They''re sometimes referred to as the fight or flight response.

The same physical changes occur, though, in response to emotional stress. Ideally, in an emergency, we use all that energy. We slay the dragon, save the maiden, outrun the attacker, whatever. But, with emotional stress, we just stew. If the stress is chronic, the physiologic changes can be debilitating and destructive to the immune system. Stressed-out people get sick more easily. Add unfit to the equation and you have a real whammy.

The good news, say the experts, is that regular exercise alters how our bodies respond to stressors. Studies show fit people are less flustered by emotional stressors and actually secrete less stress hormones in day-to-day stressful situations, says Bailey.

Even better, fit people produce an even more powerful response to unusual stressors, like real danger, than do nonexercisers.

And even better yet, says Dr. Robison, people who exercise regularly are more resistant to depression and anxiety.

Also important, Dr. Robison adds, are rest and relaxation. Exercise, rest and relaxation all are crucial for optimal functioning of mind, body and spirit—and optimal functioning is crucial for maximum immunity. The beauty is, it is within our control and reach.

Listening to the Heart

Exercisers have stronger, healthier hearts.

Regular aerobic workouts build powerful, resilient heart muscles. And regular exercise causes the body to create more of its blood-clot dissolving substance and slightly less of its clotting factor. Hearts celebrate both developments. Our hearts don''t have to push so hard to pump thinner, cleaner blood.

Are we listening to our hearts? Our hearts want us to exercise.

A program of exercise is carefully designed and prescribed when a man is rebounding from a heart attack. Why wait? A little exercise now, and we may avoid heart trouble altogether.

Just remember Dr. Swencionis''s caution not to overdo it—especially if you are not now in the exercise habit. Start slowly and carefully. "Enjoy yourself," says Dr. Robison.