That said, a Medicine & Science in Sports & Exercise study found that runners lost more weight than walkers over a six-year period, possibly because of the afterburn effect. “Running at a high intensity will create an afterburn, which is when your body continues to burn calories when you’re no longer moving,” Rubin says. She suggests starting with three 30-minute runs a week, sprinting for 30 seconds then recovering for 30 seconds to a minute.
Doing crunches until the cows come home? Stop it! When you're down to your final inches of belly fat, the dreaded crunch won't be the exercise that finally reveals your six-pack. "You can't spot reduce," Jill says. Instead, she suggests doing functional exercises that use the muscles in your core—abdominals, back, pelvic, obliques—as well as other body parts. "These exercises use more muscles, so there is a higher rate of calorie burn while you are doing them," she says. Planks are her favorite functional exercise—they activate not just your core muscles but also your arm, leg, and butt muscles.
Build more muscle: Cardio gets all the glory for melting fat, but it’s actually far more important to focus on building muscle. It’s pretty simple: Lipolysis happens in the mitochondria of the muscles, so the more muscle you have, the more mitochondria, and the more potential to burn. Plus, the more muscle mass you carry, the more your BMR is burning calories at rest. Strength training is also one of the strongest ways to spark production of testosterone and growth hormone, which both help to break down fat, Seedman adds.