When I hike 14'ers in the summer, I inevitably do not have to shit the whole prehike, or anytime in the woods, it always hits me like a ton of bricks at about 13k on the way UP (treeline is at about 11.7)

so brutal.
I lost it all the way into my shoes on top of a roof in Nebraska on a super hot summer day when I was drinking alot of Budweiser at night.