Aerobic exercise yields greater fitness, but is harder to maintain

Moderate intensity physical activity such as walking may be helpful in maintaining weight loss for some, according to research presented at the 52nd American College of Sports Medicine (ACSM) Annual Meeting in Nashville, Tenn.

Study subjects who engaged in high-intensity aerobic exercise lost no more weight than “lifestyle activity” participants, and were less likely to maintain their fitness improvements a year later.

The four-year study, funded by the National Institutes of Health, involved 104 women and 20 men who were 15-50 pounds overweight—bordering on obesity. All followed a low-fat, moderately restricted diet for four months, choosing from among options allowed by dietary guidelines.

• Traditional aerobic exercise, (40-minute sessions, four days a week);
• Short-bouts aerobic exercise (10-minute sessions, four times daily, four days a week), or
• Lifestyle activity, accumulating at least 30 minutes of moderate-intensity physical activity each day.

Those engaging in traditional aerobic exercise made greater gains in fitness than the other groups, but all three groups saw similar weight-loss results.

Following the four-month program, participants were monitored for an additional 12 months. All groups were encouraged to keep up their activity levels but were also allowed to pursue activity or exercise of their choice.

“If your goal is fitness, then traditional aerobic exercise may offer the best return,” said study coordinator Shawn Franckowiak. “If you’re looking for weight loss or health benefits such as controlling blood pressure, cholesterol or diabetes, then the novel approaches we tested may be a promising alternative to traditional exercise.

“Interestingly,” said Franckowiak. “When we allowed people to engage in their own choice of activity after treatment, those in the lifestyle activity group tended to maintain their fitness better than aerobics participants. We also learned that, in the short run, weight loss does not appear to be compromised when engaging in novel exercise routines such as lifestyle activity or short-bout aerobic exercise.”

Franckowiak hypothesized that a lifestyle program may offer opportunities to fit physical activity into a busy schedule. He said there is much more to be learned about weight loss and fitness. “This is the tip of the iceberg. We’re looking at data showing what the individuals may have done during the year.” It is possible, he said, that lifestyle activity serves as a gateway to other traditional forms of exercise.

While much research has been done on how to lose weight, the subject of how to maintain weight loss is of continuing interest—ask any dieter. “That,” said Franckowiak, “is the million-dollar question we’re trying to answer.”