A recent head-to-head comparison of aerobic training and resistance training found that when it comes to weight loss and weight maintenance, aerobic training comes out on top. If the goal is to increase lean body mass, however, resistance training is the way to go. That's according to a study(jap.physiology.org) (abstract) published in the Dec. 15 issue of the Journal of Applied Physiology.
For the study, researchers from Duke University Medical Center and the Durham Veterans Affairs Medical Center in Durham, N.C., and East Carolina University in Greenville, N.C., randomized 234 previously sedentary overweight and obese adults with no history of diabetes into three groups: aerobic training, aerobic plus resistance training, and resistance training only. Study participants' ages ranged from 18 to 70.
Participants assigned to the aerobic training group exercised vigorously -- reaching between 70 percent and 85 percent of maximum heart rate -- for about 45 minutes three days a week. Those assigned to resistance training also exercised three days a week, completing 8-12 repetitions on eight different resistance machines that targeted all major muscle groups. Participants in the combination training group performed all exercises assigned to both the aerobic and resistance groups.
Although resistance training was more effective in producing lean body mass gains, the researchers noted that it did not significantly reduce either fat mass or total body mass. Instead, aerobic training proved the more effective of the two training types for the reduction of fat and body mass.
Overall, researchers found that the groups assigned to aerobic training and aerobic plus resistance training lost more weight than those doing resistance training only. In fact, the resistance-only group actually gained weight due to an increase in lean body mass.
In addition, waist circumference decreased significantly in both the aerobic training and aerobic plus resistance training groups, but it remained steady in the resistance training-only group.
"While requiring double the time commitment, a program of combined aerobic training and resistance training did not result in a greater loss of fat mass or body mass over aerobic training," the researchers wrote in the conclusion. "If increasing muscle mass and strength is the goal, a program including resistance training is required. However, balancing time commitments against health benefits accrued, it appears that aerobic training alone is the optimal mode of exercise for reducing fat mass and total body mass."