Further to the previous post on mistakes, as I mentioned I've been thinking about the right food and water for this.
On the water front, I plan on doing some experiments around what works and what doesn't. Does adding a little bit of salt make any difference? Does water with electrolyte powder freeze any slower than just plain water? Should I start with warm or room temperature water? How to keep my hose and mouthpiece from freezing? Whats the best way to carry it? I think the best answer to all of this that I have seen is this Camelbak vest that spreads the water out over your back - its pretty low profile and perfect for wearing under other layers. But its $100! And its possible that it'll my my back sweat a lot right there. I wonder if I could make something similar for the hydropack I have? Mine isn't the best shape (it'd be more like wearing a 2 liter soda bottle on your back), but most people agree that getting the hydration pack under your outer layer is key. However, a standard camelbak backpack type carrier under my outer layer would prob work similar, though maybe slightly less comfortable. I might want a larger container, too. My current pack is 2L, which really isn't enough - 72 oz would be a little better, though heavier.
Something that might work better in practice is an insulation system from Granite Gear: cheaper, and I don't have to strip down to refill.
So next is what food freezes so solid as to be basically uneditable. Not just the rider I described before, but I've heard of other riders that have brought along their "usual" food items to these winter races only to have everything freeze. So what could work and what won't. Do small bits of Clif bar cause problems? Cheese cubes? I know that nuts will be ok. Hard candy? Gel shots? Crunchy granola bars? I also plan to "Dongsheng-ize" everything. Remove it from packages, break it up into small pieces and put it in a nalgene bottle or two so I can basically get the food out without removing gloves or mittens. This was a method hit upon by one of Eric's team on the last Antarctica trek.
So first test with putting stuff in the freezer:
- Fresh bananas: bad idea. I thought maybe it would work to have them in small pieces, but its like eating ice cubes.
- Granola bites: worked well.
- Shot Bloks: I cut these into smaller quarters of a block. They froze solid but thawed fast in my mouth without the same kind of freezing that the bananas did.
- Clif C & Mojo: both did ok in the freezer.
- Cheese: not so good, too hard.
So those are some initial tests, there are more that I'm interested in trying.