Want to lose weight? Then exercise. We all know this. But what we don’t know is what type of workout burns fat best…until now.

A recent study shows that aerobic exercise works best for burning fat – even better than resistance training to raise resting metabolic rate.

The study by researchers at Duke University is published in the most recent issue of the Journal of Applied Physiology.

Researchers divided 234 overweight or obese participants into three groups. The first group performed resistance training lifting weights three times per week, three sets per day, 8-12 repetitions per set.

“If a person is going to give me three hours of exercise a week, the way to lose fat is to spend that time doing aerobic training.”

The second group performed aerobic training on treadmills, elliptical trainers, and cycle ergometers for about 2.25 hours per week, covering a distance equivalent to about 12 miles per week.

The third group performed both activities equal to the performance of the other groups.

Participants’ caloric intake averaged about 2,000 – 2,100 calories per day, and physical activity was carefully monitored for consistency in both exertion and duration. At the end of the eight-month study period, 119 participants successfully completed the study.

The final results showed that participants of the first group, who only participated in resistance training, did not lose weight. While they did gain muscle, which increased their body weight, their fat mass was not reduced.

The participants in the third group who engaged in both resistance training and aerobic exercise did lose weight, but they did not lose a lot of fat mass. The combination group lost an average of about 3.6 pounds versus the 3.8 pounds lost by the aerobic-only group.

The combination group did see the largest reduction in waist circumference, though the figures were not great enough to be statistically significant.

Lead study author Leslie Willis, an exercise physiologist at Duke University Medical Center, states, “If a person is going to give me three hours of exercise a week, the way to lose fat is to spend that time doing aerobic training.”

Still, she warns, don’t discount resistance training yet.

“No one type of exercise will be best for every health benefit,” she states. “If increasing muscle mass and strength is the goal, a program including resistance training is required.

The Bottom Line

What this study shows is that if you have little time for a workout, you should maximize by focusing on aerobic exercise or “cardio” to see results more quickly.

13 Reasons Why Women Should Lift Weights

But it’s important to note that while resistance or strength training may not be the best way to take off weight initially, it does help maintain strong bones, raise basal (resting) metabolic rate by building lean muscle, improve muscle tone (and thus, your overall appearance), and maintain muscle strength.

These benefits are of particular importance for older adults who experience gradual muscle loss as they age. Strength training can help raise their quality of life in later years, allowing them to perform minor but important daily tasks including carrying grandchildren and lifting heavier objects.

Successful Weight Loss is No Secret

Remember – it’s short-sighted to look for the easiest or fastest way to achieve your goal. In order to get fit and stay fit, you have to change your lifestyle. Start with aerobic exercise, and supplement it with a healthful diet rich in fruits and vegetables as well as weight training. When you lose weight by committing to a lifestyle change, you can look forward to it staying off.