I think you can partially negate some of the health benefits (which are debatable) by making sure that your corn gets frequent excercise.
If my amel had her way, I am pretty sure that she would sleep pretty much all day (a kindred spirit lol). I make sure that when I handle her (every day aside from 2-3 days after she has eaten) I make her work a little bit by having her climb from hand to hand and lowering one hand so she needs to climb "uphill." I don't think that this is as much excercise as she would get constricting (which she rarely does with her f/t fuzzies), but it less risky and she gets a short workout about 4~ days a week.
From what I understand, lack of excercise is mostly an issue with breeding age females due to egg binding - although it could of course contribute to a less than healthy snake in general.
I do not have experience with this though, this is only what I have read here and in books.