I work in the oilfield, We do 13 hour shifts, for 28 days. So that is 91 hours a week...Probably a little bit more.
Its demanding, I have been here 29 days now, doing 35 this time, one week extra.
I do feel a little burned out, but I have been doing 12 hour shifts for 20 years now, I had sleep issues in the past. (Ha, and a bunch of other issues.)
On the plus side I have 3 weeks leave to look forward to in 6 days.