Or just structure your time differently, work really hard for 2 days. Take a day off, work a half day the next and work a normal day.

There are gains from working in long shifts, but if it's done everyday they completely disappear and turn negative.

You don't even need to get to 40---I have mini burnouts all the time!

I keep saying to myself this is the last epic push, and then I'll take it easy and work in a civilized way from this point forward. Now's the time...