MM, it also depends on what you're used to and comfortable with.

I've spent most of my life hiking through woods, and do it now as part of my job. Carrying a small camp axe or knife like the DFLE in my kit, for the better part of 12 hours as I'm moving through treelines doesn't even phase me. I'm used to it. As to being worn out and unable to safely swing the knife or axe, again, I've never had the issue. Not saying I don't feel winded; I just take my time when I'm setting up my camp, and set my chores so that I've gotten a chance to get my breath back.

I'm not saying this to brag or anything, merely making a point of what each individual person can become comfortable with.

I have a friend back on the East Coast that goes out for jogs with 15 pound weights strapped to each limb. Would I try it? <img src="/ubbthreads/images/graemlins/crazy.gif" alt="" /> Hell no, but bully for him being able to. Same for what each person is comfortable with handling as part of their kit.