This question is primarily addressed to those who have done knuckle pushups consistently for several years.
I've been doing 100+ knuckle pushups for about two years everyday, and I've developed fingernail problems where the cuticle (nail folds) and nail bed have disconnected from the nails. Is there a certain way to hold your fist or distribute your weight to avoid this type of problem and to fix it? I do my pushups on the first two knuckles on top of a firm, thick piece of rubber. After I'm done, I can see the imprint of my fingers and nails on the palm of my hand. Thanks for any help.