Funny that nobody has mentioned flexibility along with endurance. Being limber helps you avoid injuries if you stumble and fall, so stretching plays a HUGE in my pre-hunt preparation starting several months before Opening Day.
Okie John
Very true, but lots of us on 24 hr are 70+. Flexibility is long gone as is balance. If I didn't carry a trekking pole, I'd be on my butt several times a day.