Reversing rectal stretching?

I'm not sure if this is the best place to be asking this question, but here goes:I am 22 years old, and I recently got into fisting about three months ago. I've taken a few fists with a couple patient verses and I don't want to give it up.But I am a little concerned with my hole as it is right now. By no means do I have a good large rosebud, but when I push out without any assplay, I can see much more of my insides than I would like. I've seen other guys' holes and they look incredibly smaller than mine does in the mirror, and they are able to take a bit farther than I can. Now I haven't been bottoming for sex lately, so I don't know what tops think about the tightness, but I'm a little worried.Now, the question is what should be done. Almost everyone says just to do lower body exercises. And truth is, I haven't been going to the gym for about the last month. Some recommend some kegel exercises, too.Those sound like actionable things to do. But I never thought to ask if it would reverse stretching, or if exercise needed to be proactive.Does anyone have any insight? Or where I should direct this question?