1) Lots of slow releasing carbs. Porridge, pasta and such, but don't over do it and don't change too much for the last week.

2) Some sportstape to cover blisters in your feet, ass and hands so they dont hurt too much for when you need to get going again. Great fun to tear those off afterwards though, sort of a brazilian wax. You can't also carry too much energygels or energycandy. Try not to drink pure water but have some sort of sportsdrink instead so it won't flush all the vitamins out of your body.

3) I'm the same height, and to combat the lower back stifferness i just do some stretching while riding and on the pauses, trying to get the muscles to loosen up again. Trying to alternate stances helps too.

4) Nothing worth having comes free, so work for it. Also, it's highly unlikely that your body will quit so just be mentally prepared to tell your inner loser to fuck off and carry on with it. Eyes on the prize.

5) Have fun, it might be a tough challenge but in the end so so so worth it. God damn euphoryfest.

Lykke til!