I posted in another thread about people who engage in frequent anal sex possibly having problems with controlling their bowels when they get older. Doc_Durian posted that he didn't think this would be a problem, and I disagreed at the time. After posting a thread in this section titled 'Useful information Regarding Male Orgasm' I reasoned that perhaps doing excercises similar to kegal excercises with one's anus/rectum would prevent this. I am not sure, and I am unaware of any studies regarding this, but looking at it from a common sense standpoint it makes sense. Also as far as you "hurting" her, she definetly would have told you if you were.