Exercise Why & How Much ?
Exercise is good for us for various reasons. It helps to lower blood pressure, reduce heart disease, avoid diabetes, maybe even live longer.
How much of it is needed ?
One camp says daily physical activity like walking and gardening is enough; another suggests that near-daily doses of fairly intense exertion are needed.
Some say the total amount of physical activity, not its intensity, is what matters. They recommended that adults get 30 minutes of moderate-intensity activity every day of the week if possible. Those 30 minutes needn’t all come at the same time, however—climbing stairs at work plus a walk before dinner and mopping the floor would fill the bill.
It was seen that those men who burned at least 1,500 calories a week exercising (the equivalent of running for three hours) were 25 percent less likely to have died during the 20-year follow-up period than their more sedentary friends.
Exercise is good for us for a variety of reasons. It lowers blood pressure and cholesterol levels. It helps muscle cells efficiently process sugar and can thus prevent adult-onset diabetes. It slows or halts osteoporosis. It strengthens the heart and improves lung function. It may also lengthen life.
But exercise isn’t a one-kind-cures-all proposition. Just as you get different nutrients from different foods, you get different benefits from different types of exercise.
Weight training conditions muscles and possibly prevents back trouble or the falls that plague so many older people.
Moderate activity like walking around the block or cleaning the house can lower blood pressure.
Jogging, swimming, tennis, and other more vigorous activities make the heart and lungs work more efficiently.
If you are sedentary, begin doing low levels of exercise such as gardening or walking—this is far, far better than doing nothing. If you are already doing that, try walking briskly a few times each week. If you already walk, consider running. If you run 10 miles a week, try running 15.
In the United States today, about 50 percent of all adult deaths can be attributed to coronary heart disease. A sedentary lifestyle doubles your chances of developing this disease. By comparison, smoking increases the risk 2.5 times, and untreated high blood pressure 2.1 times. A number of studies show that when someone who is sedentary (i.e., a couch potato) increases his or her daily activity level, the risk of heart disease decreases. Unfortunately, 22 percent of U.S. adults are completely sedentary, 54 percent get some exercise, and only 24 percent actually get the recommended level of physical activity each week.