Lifting Weights Works to Control Belly Fat—For Men

Do you even lift, bro?

If yes, chances are your tummy is flatter than those who don’t, according to a new study by Harvard School of Public Health (HSPH) researchers. In fact, healthy men who did just 20 minutes of daily weight training had “less of an increase in age-related abdominal fat compared with men who spent the same amount of time doing aerobic activities.” Seriously, with TV timeouts included, that’s less than a quarter of football.

“Because aging is associated with sarcopenia, the loss of skeletal muscle mass, relying on body weight alone is insufficient for the study of healthy aging,” said the study’s lead author Rania Mekary, a researcher in HSPH’s Department of Nutrition. “Measuring waist circumference is a better indicator of healthy body composition among older adults. Engaging in resistance training or, ideally, combining it with aerobic exercise could help older adults lessen abdominal fat while increasing or preserving muscle mass.”

The study, which also notes that combining both weight training and aerobic activity led to the best results, was published online December 22 in the journal Obesity.

Prior studies that looked at weight training’s relationship to belly fat have produced mixed results, were short in duration, and were mostly focused on a specific population such as being overweight or having type 2 diabetes. This new study was conducted over a long term (12 years) and included men with a variety of BMIs.

According to the study:

Mekary and colleagues studied the physical activity, waist circumference (in centimeters (cm)), and body weight of 10,500 healthy U.S. men aged 40 and over participating in the Health Professionals Follow-up Study between 1996 and 2008. Their analysis included a comparison of changes in participants’ activity levels over the 12-year period to see which activities had the most effect on the men’s waistlines. Those who increased the amount of time spent in weight training by 20 minutes a day had less gain in their waistline (-0.67 cm) compared with men who similarly increased the amount of time they spent on moderate-to-vigorous aerobic exercise (-0.33 cm), and yard work or stair climbing (-0.16 cm). Those who increased their sedentary behaviors, such as TV watching, had a larger gain in their waistline.

“This study underscores the importance of weight training in reducing abdominal obesity, especially among the elderly,” said Frank Hu, professor of nutrition and epidemiology at HSPH and senior author of the study. “To maintain a healthy weight and waistline, it is critical to incorporate weight training with aerobic exercise.”

Even though this study looked at men only, it would be safe to assume that the same principles could be applied to women, too. Bottom line: Weight training and aerobic exercise are equally important and both should be incorporated into a healthy workout routine.