What We've Learned: Getting in Shape

February 13, 2013

As winter recedes, millions of Americans renew their pledges to eat better and exercise more. And hundreds of scientists work to discover the keys to make those efforts more successful. Here’s the latest on what Duke researchers are learning about maintaining a healthy body:

1. Hit the track, not the weights. Resistance training may be a great way to build lean muscle, but if it’s weight loss you’re after, nothing beats aerobic exercise. In the largest study ever comparing aerobics and weight training, Duke exercise physiologists have found subjects who walked twelve miles a week lost more weight than those who did just resistance training or combined aerobics with weights. And they did it while spending less time on average each week exercising.

2. Cutting carbs is still a good idea. Plans such as the Atkins diet, which slashes starchy, carbladen foods in favor of meats, dairy, and vegetables, have drawn plenty of skepticism, but the data are hard to ignore. In a review of seventeen studies of patients on low-carb diets, Duke associate professor of medicine William S. Yancy Jr. ’91 found that dieters lost an average of eighteen pounds in six months to a year, and they showed improvements in blood pressure, triglycerides, and blood sugar levels.

3. Make simple changes. People who set out to completely remake their diet and exercise habits often find the change too daunting, which only leads to frustration. Duke researchers have been experimenting with the power of small adjustments, such as adding one daily fiber supplement or eliminating one sugared beverage a day. Simple changes are easier to live with, and their healthy effects add up over time.

4. Can Twitter help your kids lose weight? Jennifer Li M.D. ’87, Duke’s chief of pediatric cardiology, recently led a group for the American Heart Association that studied the potential of social media in combating childhood obesity. While Li cautions that there’s not enough research yet on the benefits and risks of talking about weight issues online, she says texts and tweets can play an important role in encouraging and rewarding healthy habits.