Before I left on my terrible travels, my neck hurt, my shoulders were fucked, even my lower back ached, I was sleeping at 4-5am in the morning every night.
Went and came back and now?
No neck/back or shoulder issues.
My internal sleep clock has reset itself back to sleeping before 1am and I'm even waking up at 7-8am in the morning!
It's nice to wake up ready for action versus wake up at 11am...