Up to 25% of the U.S. population is affected by metabolic syndrome. Metabolic syndrome is a combination of medical disorders, such as high blood pressure, insulin resistance, and elevated triglycerides, which increase the risk of developing diabetes and cardiovascular disease. In a study published online in Circulation on July 7, 2008, investigators from Norway reported that results from a small pilot trial showed that people with metabolic syndrome might benefit from an exercise routine that includes aerobic interval training.

The investigators evaluated a total of 28 people with metabolic syndrome who were randomized to one of three groups. The participants were randomized to continuous moderate exercise, a high-intensity regimen of aerobic interval training, or no specific exercise recommendations. Each of the two exercise groups was required to exercise three times per week. After 16 weeks, the investigators found that both exercise groups lost about the same amount of weight. However, of the participants who performed high-intensity aerobic interval training, 46% no longer had metabolic syndrome. In the moderate exercise group, 37% of the participants no longer met the criteria for metabolic syndrome. This improvement was attributed solely to exercise, as no diet changes were made during the 16-week time period.

The investigators suggest that these findings might be due to the fact that high-intensity exercise requires higher heart rates, leading to an increased ability to absorb oxygen. Although larger studies are needed, these findings might debunk the American Heart Association's standard recommendation for 30 minutes per day of moderate exercise, particularly for patients with metabolic syndrome.