I read that over 2,500 people start the AT every year and that 50% quit on day 3, and another 30% quit on day 8. I get it now. By day 3 and 4, I had blisters the size of quarters on each heel, dime size on the sides of my feet, nickle size on the balls of my feet, and no skin under each of my little toes - both feet. Not to mention that they swell. It really doesn't matter how strong your legs, back, and mind are. When your feet are done for the day - you are done. We were carrying too much food, too much water, and too much clothing (saw temperatures from freezing to over 70, in 7 days- only in Missouri!). Every morning was our foot ritual - cutting pieces of Moleskin to try to build up to the same height as the blister (think of a thick cloth tape, you cut a hole for the blister to poke through). The sweat of your feet would make it slide off by the end of a 20+ mile day, so I tried taping it on. This held it - but I ended up having a skin reaction to the tape after a day or two.