I know a man who gave up smoking, drinking, sex, and rich food. He was healthy right up to the day he killed himself.
And if you have great writing, it's really easy, but if it's not so great and you have to work a little harder, I could tell where the work needed to be done but comedy is just fun.
Nothing can substitute for just plain hard work. I had to put in the time to get back. And it was a grind. It meant training and sweating every day. But I was completely committed to working out to prove to myself that I still could do it.