Many Americans see exercise as a fad or chore, or merely as a sign of personal virtue. But being physically active is natural for humans, as it is for all animals. We’re wired for it.
The largely sedentary existence of vast numbers of people in developed countries is a historical aberration of the past century, made possible primarily by labor-saving devices, motor vehicles, desk jobs and increased leisure time spent in front of TVs and computers. Our sedentary lifestyles, together with the obesity epidemic they help foster, have taken a big toll on our health. They have put a drag on the improvements in well-being and longevity made possible by medical advances and positive lifestyle changes, such as the reduction in smoking rates in recent decades.
It’s tempting to think that feeling fatigued, being winded when walking uphill and no longer being able to carry heavy bags are natural parts of aging. But many of the declines in physiological functioning we associate with getting older are largely the consequence of inactivity and being unfit. Being physically fit won’t stop the biological clock, of course, but it can slow it. “Use it or lose it” is truer than ever.
How can you make exercise a part of your daily life? By making it a habit, like brushing your teeth. That’s more likely to happen if you see it as a priority and if it’s easy to do. Find what works best for you in terms of type and timing of workouts and where you do them (at home, at a gym, outdoors). Exercising with a friend or family member or in a group may motivate you and make it more fun. To keep it interesting, you may need to vary your activities. Think outside the box—for instance, consider yoga, tai chi, ballroom dancing or bootcamp classes.
Benefits of Everyday Activities
A conscious effort to exercise and stay active is a key to good health and weight control, but unintentional activities—ordinary, daily movements such as taking the the stairs—are also important.
The four elements of fitness
There are four main elements of fitness: aerobic (cardiovascular) fitness, muscle strength, flexibility and balance. Some people, such as weight-lifters or long-distance runners, excel in just one of these. To be truly fit, you should exercise to develop all of the elements, some of which overlap and work together.
1. Cardio exercise: the heart of the matter
Aerobic (meaning “requiring air”) exercise is any prolonged, moderate-intensity activity that depends primarily on the use of oxygen to generate energy from carbohydrates and fat. These “endurance” or “cardio” activities include cycling, swimming, running, brisk walking, jumping rope and any activity that raises heart rate sufficiently for at least 10 minutes. Many sports, such as tennis, basketball, and soccer, are also largely aerobic.
Such exercise improves aerobic fitness, which is the sustained ability of the cardiorespiratory system (the heart, lungs and circulatory system) to transport oxygen to cells, especially in muscles. Aerobic fitness decreases by about 10 percent each decade after age 30, on average, but exercise can help prevent or at least slow the decline.
The cardiovascular benefits of aerobic training include a stronger, more efficient heart that’s able to pump more blood with each contraction—which can result in lower heart rate and faster recovery from exertion. It also helps keep blood vessels flexible, thus reducing blood pressure.
Aerobic capacity is best gauged by a measure called VO2 max (maximal oxygen uptake), which refers to the amount of oxygen your body is capable of using in one minute. This generally requires an all-out effort on a treadmill or bike in a sports medicine lab. However, you don’t need such testing for a general sense of how aerobically fit you are. You can tell simply by noting how well you’re able to do sustained, vigorous activities, whether it’s playing tennis or climbing stairs.
2. Strong muscles: more power to you
Not too long ago, strength (or resistance) training was thought of as something only for body builders or at least just for young men. Now it’s clear that it is crucial for everyone, especially women and older people, even those in their eighties and nineties. Most of us start losing muscle (and gain body fat) in our thirties, and by age 50 we’ve lost 10 percent of our muscle mass. After that the losses accelerate, unless we take steps to counteract this. The way to keep muscles strong is to use them, of course—and, in particular, to work them to their limit periodically.
Maintaining muscle strength has obvious benefits in daily life—as when you lift grocery bags or small children, work in the garden or shovel snow—and increases stamina and self-confidence. Strong muscles can also improve athletic performance, helping, for example, to power your golf swing or tennis serve. Muscle strength can help prevent back pain, falls and many other kinds of injuries, which are often caused by muscle weakness and imbalances.
Like any exercise that puts stress on bones, strength training also maintains or increases bone density and helps prevent osteoporosis. And even if it doesn’t result in weight loss (the weight of added muscle can cancel that of lost body fat), strength training can help you look trimmer.
Strength training should be done at least twice a week for all major muscle groups—back, chest, shoulders, arms, legs and abdominals. By strength training we don’t mean lifting very heavy weights to build bulging muscles. As generally recommended, it calls for working out against moderate resistance in order to build muscle strength and endurance. The resistance can be provided by weights (dumbbells or barbells), weight machines, special elastic bands, medicine balls or even cans of food. You can also use your own body weight as resistance, as in calisthenics such as pushups and pull-ups.
Start with light weights or other resistance, then increase gradually. Work up to a weight you can lift only eight to twelve times in a row—this is known as a set. The standard number of sets is three for each exercise. Doing five or six sets with somewhat lighter weights would enhance muscle endurance more than strength.
Get a basic strength-training routine (as well as flexibility and balance exercises) here.
Making Muscles Strong
There are two basic types of muscle fitness—muscle endurance and strength. Most workouts build both to some degree, though you can emphasize one or the other.
3. Stretching, the truth
Flexibility, the ability to move your joints through their full range of motion, is a key element of fitness that can be improved by doing stretching exercises for muscles and tendons. Being more flexible can enhance physical performance—whether in sports or everyday activities (for instance, tying your shoes, making the bed, looking over your shoulder while backing out of the driveway). Stretching can help treat or prevent back pain, relieve muscle tension and stiffness, and improve posture. When done in a slow and controlled manner, as in yoga, flexibility training can be an excellent relaxation method. Stretching can—and should—feel good.
Stretching sessions should last 10 to 20 minutes, be done at least twice a week and focus on all major muscle groups. (If you have arthritis or certain other musculoskeletal problems, you should probably stretch daily, based on the advice of a physical therapist.) You should stretch slowly and in a relaxed manner; don’t bounce. You should feel the stretch, but if there’s any pain, stop. At worst, any discomfort should be mild and brief. Overstretching can increase the risk of injury. Many people find it’s easier to stretch warm muscles, so doing five minutes of jogging or light exercise or taking a warm shower beforehand may help.
There are several ways to stretch:
- Static stretching focuses on a single muscle, with the stretch being held for 10 to 30 seconds, and each stretch repeated three to five times.
- Dynamic stretching works groups of muscles as you move during the stretch. Walking lunges and standing leg swings are examples.
- Proprioceptive neuromuscular facilitation, or PNF, is a technique in which you contract a muscle against resistance (an isometric contraction), usually provided by a partner, then relax into a static stretch of that muscle, allowing the partner to stretch it farther. There are several different PNF methods.
By the way, while many people assume that stretching, especially before a workout or sport, reduces the risk of exercise-induced injuries, most research has not supported this notion. But there are other good reasons to stretch, as described above.
How Fit are You?
One way to find out how fit you are is to take the Adult Fitness Test from the Presiden's Council on Physical Fitness, Sports, and Nutrition, which evaluates your cardio, endurance and flexibility.
4. Balance matters
People often don’t think of balance as an element of fitness, so they don’t focus on it—until they start having balance problems and begin to trip or fall. Having good balance involves the integration of various sensory and neuromotor systems, including vision, muscle strength, joint flexibility, reaction time, the vestibular system in the inner ear (which monitors motion and provides orientation clues) and the ability to sense where your body is in space. If any of these systems are not functioning properly, you can lose your balance even while just walking or standing up.
Older people often have poor balance due to loss of muscle strength, as well as reduced vision and reaction time. The risk of inner ear dysfunction increases with age. Lack of exercise, obesity, neuropathy (nerve damage) in the lower legs, alcohol, certain drugs and even wearing the wrong eyeglasses can also interfere with balance, at any age. If you are over 60 or have poor balance at any age, ask your health care provider to check your sense of balance.
If you have balance problems, it’s best to start with walking and simple exercises. Many kinds of exercise— including running, strength training and most sports—can help improve balance and agility. Any activity that increases strength, especially in your lower limbs, is worthwhile. In particular, you may want to try tai chi. Originally a Chinese martial art, this ancient practice involves slow, balanced, low-impact movements done in sequences; it improves coordination, muscle strength and all-around fitness. Studies have documented its ability to improve balance and decrease falls.
Workout props include wooden or plastic balance boards, which sit on a short base that acts as a fulcrum, as well as large vinyl exercise balls. Sold in sporting goods stores, they come with instructions about balance exercises. If you think you have serious balance problems, it’s a good idea to begin with a trainer at a gym or with a physical therapist or athletic trainer. At home, be sure to have someone spot you or at least have something to hold onto so you don’t fall. Try to do some sort of balance training for 10 to 15 minutes, three times a week.
Published January 24, 2014