When i walk upstairs my hips "catch." it's not too painful, just uncomfortable. what would cause that?

Hip health: Hip catching may be innocent, simply reflecting tight muscles and tendons that require stretching. A physical therapist or trainer can advise. Hip catch also could indicate evolving joint changes that couldbe congenital or reflecting a prior injury. An xray would sort that out. Start with careful proper stretches and range of motion exercise.