[01100011]

Depends. There was a time in my 30s(IIRC) where I had 3 contracts going at the same time. It was exhilarating. My mind was constantly humming and I was really into it. I was pulling about 80 hours a week for a few months. It really depends on the type of work and how much it engages you.

[kentosi]

The parents comment still seems to hold though. What you're talking about is a fixed time period that you knew was going to end (once the contracts' deadlines arrived).

Imagine having to continue working like that.