Pumping iron is only part of the muscle-building formula.

“Recovery is just as important,” says strength and conditioning coach Todd Durkin, author of The IMPACT! Body Plan (R221, kalahari.com). That’s because weightlifting creates microtears in your muscles and hitting the gym again too hard too soon can undermine the repair process (also known as muscle growth). “Your body needs at least one day of rest between workouts,” says Durkin. Follow his four tips to make the most of your downtime.