>>222485740It depends on the person, I guess. I mean, look at Morikawa, who's the author of Ippo, and worked with Miura when they were both young.
Both of them started their manga at around the same time, but Morikawa has consistently been churning out a chapter a week, with a few week long breaks here and there.
Granted, his art isn't as detailed as Miura's, but it's still pretty good, and Morikawa seems to be a relatively healthy, upbeat person. I watched an interview with him a while back, and he came across as a person who's got his life in order, probably because Morikawa seems to have a life outside manga. He did some boxing when he was young, and later started his own boxing club, where he occasionally works as a corner man. He's also married.
