Don't do it. If you are not used to doing this kind of hike, it really F-ing hurts after a while. First you start to get blisters, and the blisters pop and you get blisters on your blisters, and you can't NOT think about these, and your friends are motoring along because they have shoes that are made for it and well broken in. Next your legs start to get tired, and you start to trip on things, and then your whole body gets tired, and you discover you still have a ways to go, meanwhile your friends are rolling their eyes, and huffing about going so slow etc. Lots of pressure to keep up.
If you hike a lot and have the right gear, its easy, but if your a smoker, or out of shape, or think your normal runners will do it, maybe reconsider.