Torch Calories 24/7
Though cardio burns more calories than strength training during those 30 sweaty minutes, pumping iron slashes more overall. A study in The Journal of Strength and Conditioning Research found that women who completed an hour-long strength-training workout burned an average of 100 more calories in the 24 hours afterward than they did when they hadn’t lifted weights. At three sessions a week, that’s 15,600 calories a year, or about four and a half pounds of fat—without having to move a muscle.
What’s more, increasing that afterburn is as easy as upping the weight on your bar. In a study in the journal Medicine & Science in Sports & Exercise, women burned nearly twice as many calories in the two hours after their workout when they lifted 85 percent of their max load for eight reps than when they did more reps (15) at a lower weight (45 percent of their max).
There’s a longer-term benefit to all that lifting, too: Muscle accounts for about a third of the average woman’s weight, so it has a profound effect on her metabolism, says Kenneth Walsh, director of Boston University School of Medicine’s Whitaker Cardiovascular Institute. Specifically, that effect is to burn extra calories, because muscle, unlike fat, is metabolically active. In English: Muscle chews up calories even when you’re not in the gym. Replace 10 pounds of fat with 10 pounds of lean muscle and you’ll burn an additional 25 to 50 calories a day without even trying.
Target Your Trouble Spots
If you’ve ever tried to ditch the saddlebags and ended up a bra size smaller instead, you know that where you lose is as important as how much. As great as it might be to see the numbers on the scale go down, when you’re on a strict cardio-only program your victory is likely to be empty. A recent study at the University of Alabama at Birmingham compared dieters who lifted three times a week with those who did aerobic exercise for the same amount of time. Both groups ate the same number of calories, and both lost the same amount—26 pounds—but the lifters lost pure chub, while about 8 percent of the aerobicizers’ drop came from valuable muscle. Researchers have also found that lifting weights is better than cardio at whittling intra-abdominal fat—the Buddha-belly kind that’s associated with diseases from diabetes to cancer.
Just don’t rely exclusively on the scale to track your progress in the battle of the bulge. Because muscle is denser than fat, it squeezes the same amount of weight into less space. “Often, our clients’ scales won’t drop as fast, but they’ll fit into smaller jeans,” says Rachel Cosgrove, owner of Results Fitness in Santa Clarita, California. And it’s the number on the tag inside your bootcuts you want to get lower, right?