Oct 16, 2017
WHAT SCIENTISTS KNOW about muscle growth can be summarized in two words: not much. It’s long been theorized that delayed-onset muscle soreness—the aching you sometimes feel a day or two after lifting—is an indication of muscle damage done by hard training. Muscle damage is thought to be necessary, to some degree, for muscle growth. But people are most often sore when they change up their workouts or they’re brand-new to lifting, and some find they rarely get sore at all.