I give you much kudos for doing something so strenuous at that altitude. When I went to Breckenridge a year ago I was incapcitated with the worst migraine of my life for the first 3 days. Walking up with my snowboard to the top of one of the mountains at Breck was one heck of a workout!

So I can't imagine how tough that must have been, and how amazing your lung capacity and endurance must be!