A systematic review including 18 studies (14 case-control studies with a total of 5 333 cases and 10 482 controls; 4 follow-up studies with a total of 65 303 subjects) was abstracted in DARE. All 18 studies suggest a protective effect of physical activity against hip fracture. The association is strong and consistent across studies with regard to physical activity in leisure time, and physical activity from childhood to recent past.