Dr Octopus is in pretty bad shape. Why? Because he's just a normal guy with robotic tentacles, who over the past 10 years or so Marvel time has been beaten up by people with super powers once every few months. That's a very plausible scenario until you compare him to every other non-powered hero and villian in the world. Batman, Daredevil, Hawkeye, Green Arrow, etc. These guys have no powers and have been around for as long as Dr O, and not one of them has so much as a migraine problem. These guys are doing battle on an almost daily basis, probably getting beaten up 20 times for every 1 time Otto gets beaten up. Granted, they are all in peak physical condition, while Doc Ock is merely a pudgy scientist, but if we are to believe he is in that bad of shape from the relatively few fights he's been in, then there should be some signs of wear and tear on those that are constantly doing the fisticuff mambo. Look at professional boxers that have been at it for a while. Concussions take their toll. If we are to believe that vitamins and exercise will keep a hero in fighting shape forever, then Dr Octopus should at worst have severe cauliflower ear. Does he just have bad genes? Is he the Marvel version of Mr. Glass? Also, why doesn't he just clone a new body? Isn't that the tried and true method for keeping aging villians in their prime? He certainly has the resources to get it done.