"It is interesting because 70% of the weight loss is lean tissue (i.e. muscle) rather than fat. This is counterintuitive to what you would expect - everybody knows that fat is the body's high energy reserve"
"Why does this weight loss occur? In short, we don't know, but there are some possibilities which we are investigating. This work is being led by Dr Mike Stroud, consultant gastroenterologist and polar explorer. One option is that we are simply expending more calories than we are eating, similar to the profound weight loss seen in polar explorers. However this isn't the case as there is adequate food at EBC; indeed I'm munching a big bowl of cereal and full cream (UHT) milk as I type. I've not done any exercise today apart from walking around camp. I'm currently wearing an activity monitor to record my calorific expenditure and weighing my food intake to support this. This theory also doesn't explain the predominant lean tissue loss."
Worth a read but of relevnce here is the following taken from section C. Proportions of Macronutrients
"However, the plodding work of man-hauling, conducted at a low average energy intensity, particularly the case during long-distance expeditions, is well suited to fat, a substance that can only be metabolized aerobically, as opposed to carbohydrate utilization. This is because unlike marathon running, man-hauling is less affected by the body's limitations in sourcing oxygen. Furthermore, high levels of fat ingestion probably increase the time it is possible to sustain intense man-hauling, since even with the lower aerobic work rates, whole body glycogen stores will be run down after 2–3 h of 8- to 10-h work days regardless of the amount ingested (112), and so beyond this time muscles have to utilize fat as the primary energy substrate anyway. This is because the maximum rate at which exogenous carbohydrate can be oxidized is ∼1 MJ/h (240 kcal/h) (56) while man-hauling activities may require up to four times that rate of energy provision (112)"
Amazon Teknet 3000mah torch £11 led torch. It's good enough as a backup and has emergency SOS function.
Much better weight options for 5000mah+ If needed eg 12000mah for 300g £20 or 7000mah for 185g £18