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The science of exercise shows benefits beyond weight loss

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Keep it fun. Find activities you love enough to do every day. Then make them a priority.

Staying active resets your body’s biochemical balance.
Key point: Go easy, but go consistently.

Exercise is even better for you than you think, finds a groundbreaking study from Finland comparing the long-term effects of an active lifestyle.

The study was the first to look at how the metabolisms of active and inactive people differ. Exercise, it turns out, has effects right down to the subcellular level. For example, mitochondria—the power plants inside each cell in the body—appear to be more efficient at burning off fatty fuel in active people. They have lower blood levels of branched-chain amino acids (BCAA), which accumulate in the blood of people who are obese or who have diabetes.

“Researchers have theorized that the healthier our mitochondria are, the less likely we are to develop a variety of age-related diseases, including diabetes, heart disease, Parkinson’s, and Alzheimer’s,” says Dr. Susan Cheng of Harvard-affiliated Brigham and Women’s Hospital. These recent findings, she says, “raise the possibility that exercise could lead to the better overall health of a person specifically by acting on the mitochondria.”

Beyond weight loss

As scientists explore exactly what it is that exercise does, they’re finding a surprising list of physical effects that go far beyond weight loss and muscle building. These include increased insulin sensitivity (meaning a lower risk of type 2 diabetes), lower cholesterol levels, a better ratio of saturated to unsaturated fats, and biochemical markers of lowered cardiovascular risk. People who exercise regularly also have blood amino-acid profiles linked to good heart health.

“I often tell my patients that if we had the ability to put what exactly exercise does for us into a pill, it would be worth a million dollars,” says Dr. Cheng. “The irony is, of course, that exercise itself is actually free.”

That’s great for kids and spring chickens, you may be thinking, but isn’t it too late for someone who already has heart disease?

“Everybody can benefit from exercise—at any age—and even if a person has a chronic disease,” Dr. Cheng says. “People with cardiovascular disease stand to gain substantially from a regular exercise routine.”

Even people of advanced age who’ve already had a heart attack are 20% less likely to develop serious heart trouble if they participate in an aerobic exercise–based cardiac rehabilitation program.

What about people with other problems besides heart disease, such as diabetes?

“The outcomes from exercise are also better for people with conditions such as chronic heart failure, peripheral vascular disease, diabetes, asthma, arthritis, and depression,” Dr. Cheng says.

What exercise does

Many of the benefits of exercise have been known for quite a long time, notes Dr. Cheng, the author of “Interrogating the Age-Old Wisdom of Exercise,” an editorial in a recent issue of the journal Circulation. Exercise reduces weight, lowers blood pressure, prevents diabetes, improves cholesterol, increases muscle strength, improves sleep quality, improves mood, and even sharpens the mind.

“But these are all just the signs, if you will, of the multisystemic benefits of exercise,” Dr. Cheng says. “What we still don’t know is exactly how exercise is able to bring about all these wonderful benefits. Still, the Finnish study nicely confirmed that exercise reduces weight and improves cholesterol, and suggests that exercise is associated with lower levels of inflammation.”

The Finnish researchers analyzed metabolisms of seven identical and nine fraternal twin pairs, ages 50 to 74, in which one twin was active and the other was inactive for over 30 years. They then compared the metabolic profiles of 1,036 active people to those of age- and sex-matched inactive people to see whether the differences between the active and inactive twins played out in the wider population.

How much exercise is enough?

Most experts say a person should get in 30 minutes of exercise nearly every day of the week. “This can sound very daunting to a lot of people,” Dr. Cheng says. “So I usually start off by recommending something that is likely to be within their reach in the near term. More is more, but less is better than nothing.”

How hard should you work out? Not so hard that it stops being fun. Consistent moderate activity is better than occasional strenuous activity.

“In other words, it’s better to take a brisk walk every day than to do a hundred-yard dash once a week,” says Dr. Cheng.

Posted by: Dr.Health

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