Everyone knows that exercise is good for you, both for fitness and health. Exercise can improve your strength, endurance, and flexibility. These results can be realized relatively quickly, depending the type and intensity of exercise you do. As a general rule, if you start an exercise program today, you should expect to experience some improvements within a few weeks.
That may mean running or walking at a faster speed, lifting heavier weights, or coming closer to touching your toes. Aside from these improvements, participating in exercise should help you feel better doing everyday activities with fewer aches and pains.
Being active can also help you lead a longer, healthier life with a lower risk of developing chronic conditions including high blood pressure, high blood cholesterol, diabetes, and obesity. Regular physical activity can also reduce your risk of having a heart attack, stroke, or developing many types of cancer. And even if these conditions do occur, they are likely to happen later in life and be less severe. While it is relatively easy to see results in strength, flexibility, and endurance, it is difficult to “see” the improvements in health that come from regular exercise. This is the topic of my Health & Fitness column in the Aiken Standard this week.
Take blood cholesterol, for example. A cholesterol test really includes several different measures of blood lipids including LDL and HDL cholesterol. LDL is called “bad” cholesterol because it tends to contribute to atherosclerosis, the process in your arteries that leads to many heart attacks and strokes. HDL has an opposite effect, reversing cholesterol deposits in arteries, so it is called “good” cholesterol. Changes in diet and certain medications, including statins (Lipitor is an example), have been widely used to lower LDL cholesterol and, to a lesser extent, raise HDL.
Exercise is also recommended to improve blood lipids, too. However, the effect of exercise is far less impressive than even a single medication. For example, some statin drugs can lower LDL by as much as 50%, which can have a huge impact on heart attack risk. By contrast, daily exercise might only lower LDL by 10%.
There aren’t as many ways to raise HDL, but regular exercise can increase HDL by about 10%. This is dose-related, so higher doses of both drugs and exercise can have a bigger effect. But the amount of exercise most people are likely to do will have a modest effect on blood lipids.
Some people, including many physicians, see this less potent effect as evidence that exercise simply doesn’t work as well as drugs for improving blood lipids. That’s true, if you just look at the numbers. But the health benefits of exercise on these blood lipids goes beyond the total LDL and HDL.
It turns out that HDL and LDL exist in different forms. Some subtypes of LDL are more atherogenic, meaning they increase heart attack risk to a greater extent, than others. Similarly, HDL comes in different subtypes, too, some of which can reduce the risk of heart attack more.
It is becoming clear that exercise can shift the prominent subtypes of HDL and LDL to the more beneficial types. This means that even though exercise may not result in significant changes in the total LDL or HDL on your blood lipid test, it can make LDL less bad and HDL better, reducing your risk of a heart attack or stroke. Similarly, exercise also seems to have beneficial effects on blood vessels and blood glucose beyond the numbers your doctor monitors for hypertension or diabetes. So, even if your test results don’t change much, know that the benefits of exercise go beyond the numbers!
Nutrition, exercise, and health information can be confusing. But it doesn't have to be that way. What can I help you with? drparrsays@gmail.com | @drparrsays
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