06/13/2013 04:05 pm ET Updated Aug 13, 2013

Are You Busier Than the President? There's No Excuse for Not Exercising

Are you too busy to exercise? Our current president exercises regularly. So does George W. Bush, who now bicycles, but once was a runner. And Bill Clinton is a jogger. Are you busier than the president of the United States? I don't think so. You can make time for exercise if you try. The length of your life and its quality depend upon it.

In order to reap the many benefits of exercise, the CDC says you need to do aerobic exercise a minimum of 30 minutes a day, 5 days per week. Aerobic exercise is anything that involves the legs and taking in more air than when stationary. This could be walking, hiking, or bicycling at a modest pace. Or you could do a more intense workout -- jogging or faster bicycling, for example -- 20 minutes per session, 3-4 times per week. These two options produce the same benefits.

Here are a few benefits of exercise that may convince you to make time for aerobic exercise, just as our president does.

Exercise can give you more years to live. Many studies show a link between exercise and improved longevity. A group of Stanford employees over the age of 50 were followed for 21 years to see how long they lived. Half of them were runners, the other half weren't. The death rate for the less active group was 226 percent greater than that for the runners. (Here's the study.) The runners also had less disability as they entered old age.

Regular exercisers have longer telomeres than those who don't exercise. (Read more here.) A telomere is a part of your chromosome that splits into two when the cells in your body divide. This is important because most of the cells in our bodies can only divide 52 times, and they stop dividing when telomeres are too short. This is believed to be the single most important factor explaining why we age. So the longer your telomeres, the more times your cells can divide and the longer you can live.

Exercise reduces your likelihood of heart disease. If you could effectively dodge the number-one killer of Americans just by exercising, would you do it? Many studies have shown a strong relationship between aerobic exercise and prevention of cardio problems. In one, 44,000 men were followed for 12 years, none of whom had cardio problems when the study began. Men who ran just an hour or more per week were 42 percent less likely to develop cardio problems than those who didn't run.

Perhaps the most important study was done at Harvard, where researchers looked at how many cardiovascular risk factors could be avoided by regular aerobic exercise, and having a healthy weight and diet. Results showed that 74-91 percent of cardio problems could be avoided by modest but regular exercise and diet.

Exercise reduces your chances of diabetes and cancer too. If thwarting heart disease isn't enough to convince you to get moving, consider that exercise also fends off two other major killers, diabetes and many types of cancer. Research has shown that 46-87 percent of diabetes can be avoided by exercise. The National Cancer Institute has records of more than 50 studies showing that colon cancer is reduced by 30-40 percent with regular aerobic exercise. Similarly, the studies show that exercise reduces breast cancer, lung cancer, and uterine cancer -- acting like a vaccine to prevent the cancer from developing.

Exercise keeps your brain young and nimble into old age. Even brain health is dramatically helped by regular aerobic exercise. Ever had a tough decision to make or tough problem to solve? Perhaps you sat in a chair for a long time and couldn't think of an answer. Then you went for a walk or a bicycle ride, or paced back and forth in a room, and the answer came to you. Why? The exercise brought fresh nutrients and oxygen to your brain, things that improve cognitive functioning. By exercising regularly, studies show you dramatically reduce the risk of Alzheimer's disease or dementia.

Okay, with all these benefits of aerobic exercise -- and this is only a small sampling of the many benefits of exercise for long life and good health -- why aren't you doing more of it? You're not alone. The CDC found that only 20 percent of Americans are physically active. If you're not active, your chances of early death go up. A 2012 study found that more people die of inactivity than of smoking-related causes!

But that's not going to be you, hopefully. Nor will it be our presidents. Because they are buying more time by making time to exercise.

Want to find out your psychological age, as opposed to your biological age? Take an audioquiz at my website,

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