I've mucked out a pen or twenty, the ammonia (pre-biochar) in my nose, and a manure fork through a finger. Still kickin'. I think I am qualified to comment.
"You load sixteen tons, and what do you get ..."
Sing it real slow, to the rhythm of the muck-stick.
If you want to look young and thin, hang around old, fat people. Or this tiny ad:
Contemplate spending the next 20 years puttering in permaculture projects