(China Stringer Network/Reuters)

THE QUESTION People who want to keep their heart in shape usually try to do so with aerobic exercise such as running, biking or brisk walking. Might practicing yoga be a viable option as well?

THIS STUDY analyzed data from 37 randomized studies, involving 2,768 adults (average age, 50) who either practiced yoga, exercised or did no exercise. Study lengths varied, but most lasted about three months.

In that time, people who practiced yoga showed greater improvement in key cardiovascular risk factors than those who did not exercise, including lower body mass index (BMI) ratings and more weight loss, better cholesterol numbers (lower LDL and higher HDL cholesterol readings), lower blood pressure and a reduced heart rate. When comparing yoga practitioners with exercisers, the benefits relating to cardiovascular risk factors were essentially equivalent.

WHO MAY BE AFFECTED? Adults. About 84 million Americans have some type of cardiovascular disease, and one of every three deaths is caused by it. Among adults, less than half get the government recommended 2.5 hours a week of moderate-intensity aerobic exercise, and even fewer do the recommended muscle-strengthening activities (such as weight lifting or pull-ups) twice a week. Yoga combines stretching exercises, controlled breathing and relaxation techniques. Its popularity in the United States has ballooned in recent years, with nearly 10 percent of adults estimated to have at least tried the mind-body practice.

CAVEATS People in the study who did yoga practiced various styles and for differing durations and frequencies. The study did not determine the mechanism behind the observed effects of yoga, but the researchers suggested that they might stem from stress reduction.

FIND THIS STUDY Dec. 15 online issue of the European Journal of Cardiology (cpr.sagepub.com; click “Online First”)

LEARN MORE ABOUT the health benefits of yoga at www.nccam.nih.gov/health and www.mayoclinic. org.

The research described in Quick Study comes from credible, peer-reviewed journals. Nonetheless, conclusive evidence about a treatment's effectiveness is rarely found in a single study. Anyone considering changing or beginning treatment of any kind should consult with a physician.