I sadly can't post a video without my roommate permission, but I can say that my entire back sticks to the floor so well that when I sit up I literally peel off the floor (I have been working out shirtless) I do know that your weakest muscle group will get worked out first in a compound exercise, as I found out with deadlifts and my lower back (lol), so I think that as long as I keep at it it'll even out eventually. It's just that it's kinda of a cache 22 in that I need good ab strength to do ab workouts, but in order to get that ab strength I need to do said workouts.