"The key is to train large muscle groups with little rest between sets. Lift heavy weights regularly (four to five times per week) to build lean muscle mass," Chadwell said. "Maintaining muscle requires your body to use more calories. Therefore, you will burn more calories sitting on the couch binge watching TV than someone who does not lift."
Lifting heavy increases the intensity of your workout, as does cutting down the rest time to 30 to 45 seconds. Combining those two elements will help you torch calories and belly fat.
Like HIIT, this style of lifting has a potent afterburn effect, causing your body to burn calories long after you leave the gym. The added benefit is that you have a curvy, toned body. "We promise you won't get bulky," said Chadwell.