Comment by PaulDavisThe1st
3 years ago
Another related extreme case was the first person to solo-ski to the north pole. They pre-loaded, mostly on olive oil, packing on tens of kg in body fat, all of which (and more) was gone by the time they were done. I don't recall the daily calorie expenditures but it was gigantic. They did this because there is some mechanical advantage carrying a good chunk of one's energy supply directly on your own bones rather than towing it in the sled.
Fiennes and Stroud lost about 25kg each crossing Antarctica; I don’t know if they pre-loaded beforehand (hopefully they did, losing that much!) but they certainly ran a deficit as a strategic trade-off against their sled weight. Hauling a kilo of fat on a sled is definitely less efficient than carrying it on your own body.
Supposedly their calories during the expedition were primarily from butter, which they mixed into every food and even ate on its own. Apparently you get used to it.