It's no secret that muscle is more metabolically active than fat, so by having more lean muscle on your skeleton, you'll burn more calories even at rest. Fortunately, Darden says he discovered a super-efficient way to build muscle while losing weight: It's called "negative training, " and Darden tested it on more than 100 people at Gainesville Health & Fitness in Florida a few years ago. The technique involves doing the lowering part, or "eccentric phase, " of a resistance exercise very slowly. But Darden gave this old-school bodybuilding trick a tweak: He found that by using heavier weights and doing just one and a half reps very, very slowly, you can achieve remarkable results from just one or two short workouts per week.
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To get a taste of what Darden calls "negative-accentuated training, " grab two dumbbells, and stand upright with your arms straight and the weights resting against your thighs. Do a quick bicep curl to get the weights to your shoulders; that's the starting position. Now very slowly lower the dumbbells—that's the negative phase—taking 10 to 20 seconds to let them lower to your thighs. Then immediately curl the weight very slowly to your shoulders (again, it should take 10 to 20 seconds)—that's the positive phase of the lift. Finally, without pausing, do another negative movement, taking a final 10 to 20 seconds to lower the weights to your thighs. So the idea is that you'll do the negative movement for twice as long total as you do the positive movement. (Eventually, you'll want to increase to 30 seconds for each phase of this exercise.)
By doing one and a half reps of a lift, you can complete a workout in just 20 to 30 minutes—and feel like you've exercised for more than an hour. The moves are simply that tough, which is why you'll need several days for your muscles to recover.
The negative-accentuated style of weight training results in 40 to 50 percent greater stress being put on your muscles, compared to more conventional training methods, says Darden. This stimulates key hormones that boost muscular growth and oxidize fat-cell content at a faster rate. "It may be that the higher level of stress put on your muscles, combined with just the right amount of carbohydrates, decreases insulin responsiveness in fat cells to make them shrink, " says Darden.
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In addition to emphasizing this unique lifting strategy, Darden's plan also includes nine other "Fat Bombs, " or small lifestyle changes that help people gain muscle and lose weight—as much as a 30 pounds in 30 days. Among those strategies are drinking plenty of cold water to stay full and burn calories through thermogenesis, walking nightly after dinner to boost body heat and trigger increased fat loss, and following a meal plan made up of roughly 50 percent carbohydrates, 25 percent protein, and 25 percent fat.