My Grandma Jones use to tell me the loose skin that drooped down from her upper arms was called “Bat Wings” About a year or so ago I FOUND my Grandma’s bat wings under my own arms and I am not amused. But more than that!! Did you know there is a muscle under there? These exercises Tyler at WellStrong Fitness has me doing …. welllllll!!!!!!! my BAT WINGS HURT!!!