Apologies for the late update. As you might have spotted, we haven't moved today (5th January) and there's been a bit more drama and suffering than I was expecting. We set off for our mid-plateau depot yesterday morning feeling relatively strong and well-rested, but mid-way through the morning I started to feel quite ill and nauseaous, with stomach cramps that seemed to be accentuated by the tugging of my sled harness as we skied through lumpy fields of sastrugi.

The rations we received in the resupply were brilliant, but contained a lot of sugary gels and chewy energy 'blocks' compared to the food we've eaten for ten weeks, and I think I started to suffer from what a sports scientist or nutritionist would call impaired gastric emptying; I simply wasn't processing the calories I was putting in my mouth. It was a vicious cycle as the day went on and I felt weaker and weaker at the same time as the temperature started to drop and the wind (thankfully coming at our backs) became stronger. With about an hour to go until we reached the depot I realised I wasn't warming up after our break, but reasoned that we'd soon be in the tent and I could warm up then. What followed was my first ever experience of hypothermia, and not something I'm keen to repeat in a hurry. 

Tarka was in the lead when we reached the depot, and finding it (marked with a spare ski sticking out of the snow and a long streamer of fabric flapping in the wind) was a piece of cake, as we'd picked up our old tracks halfway through the day so didn't need to refer to our GPS. Tarka stopped to dig up our food and supplies and I skied on for a hundred metres or so to start pitching the tent, but realised when I stopped just how chilled and lethargic I was becoming. I don't remember an awful lot of the evening that followed, but thankfully Tarka was firing on all cylinders and made sure I was in my sleeping bag with a hot drink and a hot meal before I conked out with the most profound feeling of listless exhaustion I've ever experienced. I slept like a log but was still pretty spaced-out this morning, so we decided to stay put and recover properly for a day before carrying on. 

After spending the day in my sleeping bag, dozing, drinking and eating, and after a reassuring conversation with our doctor, Rob Conway, I'm now feeling back to my old self this evening and much stronger. The two of us are both very lean, with next-to-no body fat for insulation any more, and if we mess up our calorie intake - as I did yesterday - it's alarming how susceptible we are to the cold, and how quickly the situation can become serious, especially up here above 3,000 metres.

We've also had the chance to catch up a little personal admin and start sending some higer res photos and video back now we've picked up our Pilot. Today's photo is of us at the South Pole last week. 

If all goes to plan, we should only have another eight days on the high plateau before we start to descend quite rapidly, and I'm looking forward to seeing the mountains again, and to enjoying a little more oxygen in the air. Last up, tonight marks a bit of a threshold for me: it'll be my 73rd consecutive night living in a tent on an expedition, and my current record (set when I skied solo to the North Pole in 2004) is 72 nights, so it'll be another step into uncharted territory, pushing the outer limits of sleeping bag hygiene...