(CBS News) Exercise may be just as effective as taking medications when it comes to treating some heart disease and diabetes-related conditions, a new study reveals.
Research published on Oct. 1 in BMJ shows that there was no statistically significant difference in reduced risk between people who tried to prevent repeat coronary heart disease or treat their prediabetes with physical activity or drug treatments.
"Exercise is a potent strategy to save and extend life in coronary heart disease and other conditions," study co-author Huseyin Nac, a fellow in pharmaceutical-policy research at Harvard Medical School, told the Wall Street Journal. "We think exercise can be considered or should be considered as a viable alternative or in combination with drug therapy."
Heart disease is the leading cause of death in the U.S., killing 800,000 people each year. The Centers for Disease Control and Prevention estimate that at least 200,000 deaths from coronary heart disease -- also known as coronary artery disease, or heart disease caused by narrowing of the arteries causing reduced blood flow in the heart -- could be prevented if people controlled their obesity-related risk factors, for example by eating better, exercising and not smoking.
A Harvard study showed that as little as 2.5 hours of moderate exercise a week was shown to dramatically reduce heart disease risk by 14 percent.
But a New England Journal of Medicine study showed that getting rid of extra weight may not help lower the risk of heart attacks and strokes for those with Type 2 diabetes. However, losing the pounds was shown to improve quality of life, reduce some blood vessel complications, lower the risk of depression and reduce medical costs.
For this new review, researchers looked at data from 305 randomized controlled trials with 339,274 participants. The studies looked at four different health conditions: Type 2 diabetes, repeat coronary heart disease, repeat strokes and heart failure. The vast majority of the participants were put on medication, while about 14,700 were told to exercise.
In addition to being effective in reducing repeat coronary heart disease, physical activity also helped treat prediabetes, a condition of higher-than-normal blood glucose levels that usually develops before a person is diagnosed with type 2 diabetes. Exercise was shown to be more effective than medication at preventing second strokes.
However, diuretic medication was shown to be better than exercise in preventing heart failure.
The researchers recommended that doctors emphasize the importance of physical activity in maintaining good health.
"In cases where drug options provide only modest benefit, patients deserve to understand the relative impact that physical activity might have on their condition," the authors wrote.
The Centers for Disease Control and Prevention recommend that adults get at least 150 minutes of moderate-intensity aerobic activity or 75 minutes of vigorous-intensity aerobic activity every week. They also suggest that people do muscle-strengthening activities on two or more days a week.
Physical activity has also been shown to reduce depression in heart failure patients.
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