The latest studies all confirm that belly fat is bad news when it comes to your health. But if you happen to be one of the millions of Americans who are plagued by a midriff bulge, it can be difficult to trim the fat. Now researchers say the best way to lose that belly fat — and to keep it from accumulating in the first place — is to add strength training to your exercise regimen.

According to researchers from the Harvard School of Public Health, exercisers who combine aerobic activities with weight or resistance training are most likely to preserve muscle and prevent weight gain, especially around the midsection.

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

For the study, researchers looked at the BMI, or body mass index, of more than 10,000 healthy men aged 40 and older from 1996 to 2008. They also evaluated each participant's activity level, weight, and hip-to-waist ratio to get a better idea of which exercises had the most effect on weight gain and belly fat.

The study, which was published in a recent issue of the journal Obesity, found that the men who did 20 minutes of weight training every day had a smaller increase in belly fat than the men who spent the same amount of time exercising but without the weights. Not surprisingly, they also found that the men who became less active over the course of the study were the most likely to have an increase in body fat.

The researchers are pretty confident that the results were be similar for female subjects. “Although we did not look at women, we certainly predict similar results in women,” says study author Rania Mekary, Ph.D., a researcher in the department of nutrition at Harvard School of Public Health.

Not sure how to get started? Try these ideas for the strength training moves that work best with each body type.

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Want to lose your belly fat? Pick up some weights
New research shows that the best way to beat the midriff bulge is to add weight training to your daily workout.