Researchers from Johns Hopkins and Arizona State universities have found that pumping iron burns calories for up to two hours after a workout, while jogging and aerobics classes work for less than half an hour.
Exercises that get your heart pumping and chest heaving burn more calories during the workout, but increase your metabolismwhich helps you fight fatfor a shorter time.
Carol Binzen, lead author of the report, said, "Women who want to lose weight typically do aerobic exercise to raise their heart rate, thinking that's how they can burn the most calories. To get the maximum benefit, women need a combination of cardiovascular workouts and resistance training."
Researchers studied 12 women who regularly did weight-lifting exercises. On one day they were asked to exercise on resistance equipment and on another to watch a film. The results, published in the latest issue of Medicine, Science Sports and Exercise, showed that weight trainers burned up to 155 calories during exercise, compared with just 50 calories while relaxing.
Ms Binzen said, "It might not seem like the exercise burned many more calories, but up to two hours after their workout the women continued to have elevated metabolism." She added that resistance equipment was especially important for women over 25, who lost up to half a pound of muscle mass every year.
The National Osteoporosis Society said it was vital for women to carry out some load-bearing exercise to maintain bone strength and cut their risk of osteoporosis.
(c) Health Media Ltd 2001