When Doctors Don’t Know the Best Medical Advice

Old Medical Advice: Do cardio exercises to lose weight. Cardio exercise has been the gold standard for shedding pounds since the concept was introduced to mainstream America by physician Kenneth Cooper in his 1968 book, Aerobics, which coined the term and publicized the importance of cardiovascular fitness for controlling weight and promoting health. We’ve been jogging, running, biking, and elliptical training ever since.

New Medical Advice: Science now shows that quality trumps quantity: Short bursts of intense physical activity called intervals are the best workout for weight loss. In a study from the University of New South Wales, in Australia, women who did 20 minutes of sprints on a stationary bike (eight seconds of all-out effort followed by 12 seconds of recovery) three times a week shed nearly three times as much fat after about four months as did a group of women who performed 40 minutes of moderate-intensity cycling.

Intervals torch more calories than regular cardio and stoke metabolism so you keep burning post-workout.

Plus, a shorter session at the gym means you’re less likely to overeat afterward. Recent research published in the American Journal of Physiology found that people who logged an hour of exercise a day shed the same amount of weight as those who did half as much, probably because those who worked out longer ate and rested more throughout the day. For best results, combine intervals with strength training. Lifting weights increases lean muscle mass, which can rev metabolism too.

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