Cardio is essential for weight loss, but you shouldn't ignore strength training, either. Not only does lifting weights burn calories in and of itself, but building lean muscle will help you burn more calories at rest. "I would recommend two days of strength training a week of full-body exercises for maintenance," he said. If you want to bump that up, trainer and fitness expert Jillian Michaels recommends weight training up to four times a week.
But if you're tracking your progress simply from the scale, you may not notice it budging much each week if you strength train more often. As you build muscle, it will change your body composition, but the number on the scale may stay the same. That's why it's important to track your progress using other methods such as measurements, how your clothes fit, and before and after photos.