Aerobic exercise combined with resistance training is the best choice for teenagers striving to lose weight, a new report concludes. Exercise is often recommended for teenagers who wish to lose weight, but few studies have been conducted on which forms of workouts were most effective.
Researchers examined 304 teen subjects from Canada, each of whom had previously refrained from undertaking any regular form of exercise. Volunteers, all between the ages of 14 and 18, were separated into four groups. One group practiced resistance training, such as weight-lifting, while the second undertook purely aerobic exercise, such as walking on a treadmill. The third group utilized both forms of exercise, and the fourth group did neither, acting as a control for the experiment.
University of Calgary investigators found that teens who undertook both forms of exercise lost more weight than teens from the other three groups.
"Remarkably, among participants who completed at least 70 per cent of the prescribed exercise sessions, waist circumference decreased close to [three inches] in those randomized to combined aerobic plus resistance exercise, versus about [one-and-a-half inches] in those randomized to do just one type of exercise, with no change in those randomized to diet alone," Glen Kenny from the University of Ottawa, one of the principal researchers on the study, said.
Subjects participating in aerobic exercise alone lost 2.5 percent of their body fat, compared to 3.2 percent for those utilizing resistance training. Teenagers utilizing both forms of exercise lost 4.8 percent of their body fat.
Teens in the three groups participating in exercise routines were supervised by personal trainers. They took part in workouts four times a week for 22 weeks, as part of the study. Body fat changes were monitored using Magnetic Resonance Imaging (MRI) devices.
Resistance training can be attractive to people facing challenges with their weight, as jogging or bicycling can be difficult with extra pounds. Muscles also build faster than weight is lost, giving heavier people a chance to see their bodies respond positively to their efforts.
Researchers also found that changes to diet were largely ineffective unless they were combined with a regular exercise routine.
Obesity in teens continues to adulthood in 80 percent of the people studied. This excess weight can lead to a myriad of health problems, including diabetes, cancer, and heart disease.
Researchers on the study hope that their work will lead to an increased knowledge of the problem of teenage obesity in the United States. This could lead to a consistent strategy in dealing with the issue, investigators believe.
Analysis of various forms of exercise for teens, and their effects on weight loss, was profiled in the Journal of the American Medical Association (JAMA) Pediatrics.
