Aerobics

Aerobics

Take a Sip from the
Fountain of Youth

What do you think of when you hear the word "aerobics"? Chances are it's aerobics class, the one you faithfully attend two or three days a week--whenever you have time.

Aerobics classes are one of the most popular activities at health clubs these days, particularly among women. So much so that "aerobics" has become kind of a buzzword for fitness.

And that's fitting. Aerobics classes rev up your heart, usually last from 20 minutes to an hour and work your major muscle groups, improving your cardiovascular system and getting you fit.

But the term aerobics extends well beyond your gym classes. A whole range of exercises--biking, running, walking and swimming, for example--are aerobic. And they can do more than make you feel fit. They can make you feel younger, both today and in the years to come. In fact, when it comes to age erasers, aerobic exercise is right at the head of the list. Its benefits are long ranging.

Aerobic exercise helps combat aging by preventing heart disease, maintaining bone and muscle strength and keeping your mind sharp. It may also play a role in fending off diabetes and certain forms of cancer. And it can help take the edge off daily stress by boosting your mood and energy level. Premenstrual syndrome (PMS) and menopausal symptoms are often reduced with exercise.

"The cliché is that if ever there were a Fountain of Youth, this is it," says William Simpson, M.D., professor of family medicine in the Department of Family Medicine at the Medical University of South Carolina in Charleston. The person who regularly engages in aerobic exercise along with resistance training really has the optimal physical preparation for aging, he says.

A Friend of the Heart

A major benefit of aerobic exercise is its effect on your heart and cardiovascular system. Evidence shows that aerobic exercise helps decrease the risk of cardiovascular disease, the number-one killer of both men and women in the United States, says Alan Mikesky, Ph.D., an exercise physiologist and professor at Indiana University School of Physical Education in Indianapolis. And that's the main reason aerobic exercise should be a priority, he says.

The amount of protection exercise offers against heart disease in women isn't known, says Dr. Simpson. That's because studies over the last two decades have concentrated on men. "There really haven't been large studies with females yet," he says. But researchers suspect that women reap the same benefits as men.

Research shows that aerobic exercise can decrease the risk of a first heart attack in men. In a study of 16,936 Harvard alumni ages 35 to 74, men who were less active were at 64 percent higher risk for a first heart attack than more active men.

Compelling data also indicate that sedentary men have a 30 to 40 percent greater risk of death from coronary heart disease than men who burn over 1,000 calories a week exercising--the equivalent of walking ten miles (about 40 minutes a day, three to four times a week).

Pump It Up So the Pressure Goes Down

Aerobic exercise can help lower your risk of heart disease by strengthening the heart and making it more efficient. When you exercise, your muscles require more fuel--oxygen, that is. So your heart pumps harder in order to push more blood--the vehicle that transports oxygen--to the outlying muscles. When the heart works harder like this on a regular basis, it grows stronger and more efficient, says Dr. Simpson. "You get a stronger pump working."

Exercise also helps improve the quality of circulation. "Exercise tends to dilate vessels so that the heart can pump more easily to supply blood to the rest of the body," says Dr. Simpson. The result is that resting blood pressure declines. "The heart doesn't have to work as hard against resistance."

Aerobic exercise also helps increase your metabolic rate--the rate at which your body burns calories. At heart-pumping levels, exercise burns enough calories to reduce body fat, thus leading to weight loss.

Keeping trim not only helps you feel better but it can also help keep down blood pressure, a major risk factor for heart disease. Studies indicate that blood pressure can also be reduced by exercising at least three times a week. And in one study of 641 women ages 50 to 89 conducted at the University of California, San Diego, blood pressure was significantly lower in active women compared with sedentary women.

Clobber That Cholesterol

Exercise may also help to decrease your risk of heart disease by keeping your cholesterol under control. Studies show that exercise increases HDL (high-density lipoprotein) cholesterol, the good cholesterol that helps sweep LDL (low-density lipoprotein) cholesterol, the bad cholesterol, from the arteries. High-intensity exercise has been shown to increase HDL levels 5 to 15 percent.

Research indicates that aerobic exercise increases HDL cholesterol levels in women as well as in men. When women engage in regular exercise--say, the recommended 30 minutes of exercise three times a week at a minimum of 50 percent of maximum heart rate (220 minus your age)--elevated cholesterol levels tend to decline.

The good news for women is that they may not have to work as hard as men to get the same results. For women, moderate levels of exercise appear to be effective in raising HDL. Men, on the other hand, seem to require more strenuous exercise.

A Good Way to Bone Up

Aerobic exercise is effective in helping to maintain bone strength as well. Weight-bearing exercise places stress on the bone, and that stress helps maintain or increase bone strength. This is important particularly in postmenopausal women, who experience rapid bone loss at the rate of 2 to 4 percent per year.

The decline in bone density that occurs with aging, known as osteoporosis, is responsible for 1.3 million bone fractures per year. One-third of women older than 65 get spinal fractures and 15 percent fracture their hips.

Aerobic exercises that are particularly effective are weight-bearing ones such as walking and running. Even riding a bicycle, either stationary or moving, can be effective. Just increase the resistance against which you are pedaling, says Sydney Bonnick, M.D., director of osteoporosis services at Texas Woman's University in Denton. "That strengthens the muscles of the upper hips and thighs so they pull on the bone, which is a good stimulus to bone growth," she says. Unfortunately, a popular exercise for older women, swimming, is not weight-bearing and appears to be less effective.

A Matter of Memory Maintenance

Did you know that exercise can keep you younger by fending off the decline of your mental fitness? Well it can, according to Joanne Stevenson, R.N., Ph.D., professor of nursing at Ohio State University College of Nursing in Columbus who specializes in how exercise affects memory in the elderly.

Long-term memory--the ability to remember distant events--doesn't generally deteriorate with aging. But short-term memory--the ability to remember recent events--does. Part of the reason for this, says Dr. Stevenson, is that as we get older, brain cells don't receive the same level of nutrients and oxygen that they used to. Aerobic exercise can decelerate that. It also helps increase the number of brain chemicals called neurotransmitters so that messages can be carried more quickly across brain cells, she says. "Exercise, by maintaining a high nutrient level and high oxygenation level, sort of wards off the process of aging."

Aging can also affect what researchers call fluid intelligence--your ability to conceptualize. This type of memory requires more oxygen to the brain than any other mental chore. "Real quick thinking and real quick gaining of ideas--getting the whole gestalt--slows down through middle adulthood and into old age," says Dr. Stevenson. "Aerobic exercise would slow down this slow-down," she says, and enable people to maintain mental flexibility and quickness for a longer period of time.

Disease Deterrence

Exercise may also play a role in fending off diabetes and cancer.

Type II diabetes, a disease in which the body produces less insulin and becomes insulin resistant, affects 10 to 12 million adults age 20 or over. Preliminary evidence suggests that exercise helps increase insulin sensitivity and resistance to the disease.

In one study of 87,253 women ages 34 to 59 conducted at the Channing Laboratory of Harvard Medical School and Brigham and Women's Hospital, both in Boston, women who exercised vigorously at least once a week reduced their risk of diabetes.

In another study of 5,990 male alumni of the University of Pennsylvania in Philadelphia, the incidence of diabetes declined as physical activity went up. For every additional 500 calories burned through activity, the risk of diabetes went down by 6%. The study indicates that increasing physical activity may help prevent or delay diabetes and that vigorous activities may have a greater impact than more moderate ones.

Physical activity may play a role in deterring cancer, particularly colon cancer. In a study of 17,148 Harvard alumni, those who were highly active lowered their risk of colon cancer by 15 percent compared with inactive alumni. Researchers suspect that exercise may protect against colon cancer probably by reducing the amount of time that potential cancer-causing agents take to move through the intestinal system.

The Immediate Return

Aerobic exercise can make you feel younger today by boosting your self-esteem and improving your mental attitude. Regular exercise produces several rewards--muscle strength, gains in your aerobic fitness level, feelings of control over your environment and positive feedback from friends you exercise with--that can make you feel better about yourself.

One study of 26 college athletes found that a 30-minute session of riding a special exercise cycle reduced anxiety significantly and that the effect continued for as long as an hour after the exercise session.

Aerobic exercise can also help fight fatigue. "Despite what people sometimes feel, an exercise program tends to increase energy levels rather than decrease them," says Dr. Simpson. If people stop and pay attention to how they feel after exercise, they will recognize that they feel more alert and more energetic, and that those feelings can carry over several hours after the exercise session, he says.

Exercise probably helps reduce anxiety and fatigue by boosting endorphin levels, the body's natural mood elevators. Women who exercise regularly also find that exercise helps decrease PMS symptoms such as anxiety, irritability and depression as well as the feelings of depression that can accompany menopause.

Endorphins may also serve as the body's natural painkillers. That might be why regular physical activity, which triggers endorphin release, can help reduce premenstrual cramping.

With all these benefits it should come as no surprise that aerobic exercise may help you live longer. In a study of 3,120 adult women conducted by the Cooper Institute for Aerobics Research in Dallas, the higher their level of physical fitness, the lower their death rates.

A follow-up to a Harvard study found that by the time they were 80 years old, men who had gotten adequate exercise between the ages of 35 and 79 lived one to two years longer than men who didn't get regular exercise.

What the Doctors Recommend

The general guidelines for aerobic exercise have been to get 30 minutes of continuous aerobic exercise that gets your heart rate up to between 50 percent and 90 percent of your maximum heart rate at least three times a week. How high you need to raise your heart rate to reap anti-aging benefits depends on your age, sex and current fitness level. Generally speaking, women who have a low fitness level should aim for an exercise intensity between 50 and 65 percent of their maximum heart rate. Women of average fitness status should aim for between 70 and 75 percent of their maximum heart rate and women in excellent shape should aim for between 80 and 90 percent of their maximum heart rate.

Statistics show that only 22 percent of Americans get the recommended 30 minutes three times a week. So if getting that much exercise is out of the question for you, try instead to accumulate 30 minutes of exercise over the course of the day--say by walking 10 minutes before work, 10 minutes at lunch and 10 minutes after you get home. There is growing evidence to suggest it is the cumulative amount of activity, not the amount done at any one time, that can reap long-term health benefits.

Getting to It

It's one thing to know you should exercise, but it's another thing to get going and stick with it. Here are some tips to help you out.

Get physical. A physical checkup, that is. If you're just starting an exercise program, see your doctor. She'll check to see if you've ever smoked or whether you have a family history of heart disease, high blood pressure, high cholesterol, premature death or heart attack, says Dr. Simpson. During the physical exam your doctor will assess your blood pressure and check to see if you have had any previous injuries to your muscles or bones that could be exacerbated by exercise, he says. If you haven't exercised in the past, are over 35 and have risk factors for heart disease, your doctor may recommend a stress electrocardiogram or a treadmill test.

Get some guidance. When you first start out on your exercise program, it's very important to get supervision from someone who knows about exercise, says Janet P. Wallace, Ph.D., associate professor of kinesiology at Indiana University at Bloomington. On your own you'll tend to overdo it, so find a trainer to keep you at the right pace. Ask candidates if they have certification from the American College of Sports Medicine, the American Council on Exercise, the Aerobics and Fitness Association of America or the National Strength and Conditioning Association. Working with a trainer may also keep you on the exercise bandwagon, says Dr. Stevenson. This is because if you actually make an appointment to work out, you're less likely to forgo exercise for a few hours on the sofa at home.

Make it a priority. Instead of looking at exercise as a leisure activity, look at it as a necessity, says Dr. Mikesky. In other words, make an appointment with yourself to get exercise, and decide that it can't be canceled, postponed or rescheduled. Respect that appointment just like you would any other.

Warm up. It's important to warm up and stretch before plunging headlong into your workout session. Warming up increases circulation to the muscles, makes them more pliable and helps prevent injury, says Mark Taranta, a physical therapist and director of the Physical Therapy Practice in Philadelphia. Try walking, jogging slowly or riding an exercise bike at a slow pace for a few minutes until you get a light sweat going. Then stretch for eight to ten minutes.

Make it fun. People are more successful getting into a regular exercise program when they choose an activity they enjoy, says Dr. Wallace. If it's boring or too hard, you won't stick with it, so try different things until you find a type of exercise you really like.

Mix it up. "Aerobic activities are not the most exciting activities," says Dr. Wallace, so try combining them with another activity that you like. If you enjoy racquetball or tennis (anaerobic activities), try walking for 15 minutes before or after. Or combine different types of aerobic activities. "If you're at the health club with a lot of aerobic equipment, move from one to the next," she says. Spending ten minutes on each one will be less boring. So try the stair climber, then the bike and then the treadmill.

Couple up. Consider going to the gym with your partner, says Dr. Wallace. A study of 16 married couples at her institution found that the dropout rate for individuals who went to the gym with their spouses was much lower (6 percent) compared with those who went to the gym on their own (42 percent). You don't necessarily have to work out together; just plan on going there together, says Dr. Wallace.

Get in a group. If you really have trouble exercising on your own, aim for a group activity. Join an aerobics class or a running group. Start your own walking club with friends from work. Exercising with others will help you stick with it, says Dr. Stevenson, because you'll have to answer for yourself. If you miss a class one week, the next week someone will be asking where you were, she says.

Give yourself a break. Getting in a regular exercise routine can take some time, so allow yourself to slip up here and there. Take it a week at a time, says Dr. Wallace. "If you blow it one day or one week, you still have next week," she says.