There are really only two requirements when it comes to exercise. One is that you do it. The other is that you continue to do it.
Regular physical activity that is performed at least five days a week reduces the risk of developing or dying from some of the leading causes of illness and death in the United States. In fact, regular physical activity can reduce the risk of dying prematurely from heart disease, diabetes, high blood pressure, cancer, and developing diabetes. Exercise can also help you sleep, control weight, build and maintain healthy bones and joints and help older adults become stronger and better able to move about without falling.
Exercise and Heart Disease
Numerous scientific reports have examined the relationships between physical activity, physical fitness, and cardiovascular health. Expert panels, convened by organizations such as the Centers for Disease Control and Prevention (CDC), the American College of Sports Medicine (ACSM), and the American Heart Association (AHA), along with the 1996 US Surgeon General’s Report on Physical Activity and Health, reinforced scientific evidence linking regular physical activity to various measures of cardiovascular health. The prevailing view in these reports is that more active or fit individuals tend to develop less coronary heart disease (CHD) than their sedentary counterparts. If coronary heart disease develops in active or fit individuals, it occurs at a later age and tends to be less severe.
Exercise and Diabetes
Glucose tolerance and insulin sensitivity can be reversed by regular exercise. For most people the body’s ability to use glucose in the blood stream declines with age. As people develop more body fat and less muscle, their muscle tissue becomes less and less sensitive to insulin. As a consequence, it takes more and more insulin to have the desired effect. Once again, though, increasing your muscle-to-fat ratio can reverse this deterioration, improve your blood-sugar tolerance, keep your insulin sensitivity high, and greatly reduce the chances you’ll ever develop diabetes.
Can exercise even prevent diabetes? A study published in The New England Journal of Medicine in 2002 sought to find out. The study, known as the Diabetes Prevention Program, took 3,234 people with prediabetes and divided them into three groups. One group took the diabetes drug metformin, another group took a placebo, and those in the third group were asked to eat less fat and reduce calories while following a regular program of moderate exercise.
The results were amazing. Compared to that in the placebo group, the incidence of diabetes in the diet-and-exercise group was a whopping 58 percent lower. Those over the age of sixty in the diet-and-exercise group experienced the greatest improvement, lowering their risk of diabetes by 71 percent. Nearly one-third of the people in the diet-and-exercise group actually reversed their prediabetes, seeing their blood glucose levels come down into the normal range.
Exercise and High Blood Pressure
Becoming more active can lower your systolic blood pressure — the top number in a blood pressure reading — by an average of 5 to 10 millimeters of mercury (mm Hg). That’s as good as some blood pressure medications. For some people, getting some exercise is enough to reduce the need for blood pressure medication. If your blood pressure is at a desirable level — less than 120/80 mm Hg — exercise can keep it from rising as you age. Regular exercise also helps you maintain a healthy weight, another important way to control blood pressure.
Exercise and Cancer
“Physical activity is central to reducing your risk of cancer,” says provider Michael Thun, vice president emeritus for epidemiology and surveillance at the American Cancer Society. “There are two ways that regular exercise can potentially do that,” he explains. It can indirectly lower your risk by keeping off excess weight, or it can work directly on cancer risk. “With respect to colon cancer, the direct effect is very well documented. Studies show that even light to moderate regular activity is associated with lower risk compared with inactivity.”
Researchers tracked some 119,000 women in their 50s and 60s for seven years in the U.S. NIHAARP Diet and Health Study. Those who reported more than an hour a day of moderate to vigorous activity—even if they hadn’t exercised earlier in their lives—were 16 per cent less likely to be diagnosed with breast cancer than those who rarely did moderate to vigorous exercise.
Because of the this mounting evidence the American Cancer Society now recommends at least 30 minutes of moderate to vigorous physical activity at least five days a week, but says that 45 to 60 minutes is preferable.
Exercise and Sleep
Exercise promotes better sleep, too. In a study published in The Journal of the American Medical Association in 1997, epidemiologist Abby C. King and her colleagues at the Stanford University School of Medicine found that people who exercised regularly slept almost an hour longer each night and fell asleep in half the time, it took others.
Exercise and Weight
Physical activity helps to reduce body fat by building or preserving muscle mass and improving the body’s ability to use calories. By increasing muscle strength and endurance and improving flexibility and posture, regular exercise helps to prevent back pain. Regular weight-bearing exercise also promotes bone formation and may prevent many forms of bone loss associated with aging.
Most people gain fat as they age even if they aren’t gaining weight. Their musculature shrinks while fat tissue accumulates. This is particularly true in sedentary people. In the United States and similar societies today, the average twenty-five-year-old woman has 25 percent body fat. If she’s sedentary, by the time she’s sixty-five her body-fat level will rise to 45 percent. And a similar pattern holds for men. The average American man at age twenty-five has about 18 percent body fat. If he’s sedentary, by sixty-five he will have nearly 40 percent body fat. Simply put, increasing the strength of our muscles and decreasing the amount of body fat we carry around is one of the most meaningful steps we can take on the path to healthy aging.
Exercise and Aging
You are never too old to exercise. Dozens of studies have documented that you can build up your muscles and increase your strength with resistance or weight training no matter how old you are. It wasn’t that long ago that many experts thought vigorous exercise might be okay for younger people, but it was dangerous for people over fifty. Such was the prevailing belief in the 1960s, when the epidemiologist and provider, Ralph Paffenbarger embarked on the landmark College the Alumni Health Study, investigating the exercise habits of more than fifty thousand University of Pennsylvania and Harvard College alumni.
Dr. Paffenbarger and his associates tracked their subjects’ health and activity levels for four decades and found that participants’ death rates fell in direct proportion to the number of calories they burned each week. The more active they are, the longer they live. The data clearly showed that if you become and remain physically active, you would live longer. And the study has also provided good news…It’s never too late to change from a sedentary to an active lifestyle, nor to benefit from that change.
A study at Tufts University found that after two months of lifting weights 3 x per week, chronically ill nursing-home residents tripled their walking speed and improved their balance by 100%. Many gave up their canes. The research also showed that simple strength training exercises can help keep women from needing canes in the first place.
Aniansoon A et all 1981; Frontera WR et al 1992
AJohn Briley. “Feel Good After a Workout? Well, Good for You.” Washington Post, Tuesday, April 25, 2006.
Chobanian AV, et al. The seventh report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure. New England Journal of Medicine. 2003;289:2560.
Pate RR, Pratt MP, Blair SN, et al. Physical activity and public health: a recommendation from the Centers for Disease Control and Prevention and the
College of Sports Medicine. JAMA,. 1995; 273: 402–407.