The backpacks were oppressively heavy, and soon our shoulders, hips, and feet all ached. Ferg and I had made painstaking efforts to reduce the weight we carried, packing only ultra-light gear, leaving anything extraneous behind. Despite carefully planning every part of our menu to maximize calories and minimize weight, food still made up the bulk of our load. Ten days is generally accepted as the upper limit for self supported travel. (Sleds and pulks can of course extend this by taking the load off the back.) Beyond this length of time, loads grow prohibitively heavy, and physical strain and suffering increase exponentially. On longer expeditions, pack animals, food caches, helicopter drops, or some other form of resupply are normally employed. In preparation for an expedition to Tibet I was planning, we had chosen to push our limits, or more correctly find them, and were carrying eighteen days of supplies. Our food bags alone weighed sixty pounds (27 kg).
More than a month before we had begun dehydrating stores and packing individual meals. For each breakfast we carried three packets of instant oatmeal, along with a precious ration of coffee, one teaspoon of milk powder, and one teaspoon of brown sugar. During the day we would snack on granola bars, nuts, beef jerky, and hard candies. We also carried a high energy powdered drink mix, enough to make two litres per person per day, which would provide us with a precious thousand calories. Our dinners alternated between rice and pasta, each cooked with a cup of dehydrated meat and vegetables. A mug of herbal tea would be our dessert. A day’s rations looked meager, weighing just a few pounds and hardly filling two cupped hands. But when multiplied by eighteen, the estimated length of the journey, it was all we could manage. Unfortunately the three thousand five hundred calories it provided us with were a far cry from the estimated six to eight thousand that we would burn daily, and neither of us was sure how our bodies would respond to the deficit.
Ignoring the aches and pains of getting under way, Ferg and I chatted absently together as we walked and made quick progress. Michael dropped further and further behind as the day ground on, despite our frequent stops to wait for him. By mid afternoon he grew tired and frustrated, waved us on when he spied us sitting by the trails edge on our packs, insisting that we continue at our own pace. Before Ferg and I set