So this is what it feels like to carry 35lbs of weight on your back. I have to say, it was that single idea that worried me the most when I signed up for this 5-day trip to the North Cascades in Washington State. Forget the fact that I pretty much have no experience with camping, it was the idea of carrying a heavy pack up and down mountain passes for miles on end that concerned me. Especially seeing as I signed up only four weeks in advance and pretty much had no training time. It would, I knew, come down to how good my base fitness level was. And…