This story originally appeared in Well+Good.
Raise your hand if you’ve ever noticed that muscles like your quads or your calves remain sore for days longer than smaller ones like your biceps. Muscle recovery depends on more than just how often you’re working certain parts of your bod. According to Amy Baxter, MD, FAAP, a physician and pain researcher, three factors dictate how fast a muscle can recover: the muscle’s size, the muscle’s function, and its attachments (aka what body parts it’s connected to).