Here is a summary of what I went through at the North Pole Marathon in 2014 (have pictures but not able to send through here due to error, can send via email if wanted)
Excitement was definitely in the air at the start of the race, we were told that it was about -30 celsius at the start. We were held up for a few minutes for pictures which seemed like an eternity at that temperature, and I just wanted to get going! The course was about a 2.2 mile loop around the Barneo camp, so we had to complete a total of 12 laps to complete the full marathon distance. .2 miles was a nice stretch along the runway which was rock solid ice which made easy to run through. The other two miles were utter nightmare. The course would take you around the camp on mostly soft snow, where running at any type of pace was extremely challenging, and then the other half of the course, the snow was ankle deep. I was not prepared for the amount of exertion it required to just maneuver it. Nonetheless, the first lap is all excitement and I completed it quite quickly. During the second lap, I begin to notice that since all runners have completed the first lap, the snow was getting even softer and more difficult to run on. I didn’t even want to imagine what it would be like in lap 4, 6 or 10!! At the end of every lap you can stop at the tent to warm up and drink some fluids. Here where I should have known that troubles where ahead, cold water was not readily available at the camp. The Russians were selling cold water, but by the time I bought my share they were down to only one water bottle, luckily one of the guards gave me his thermo with some additional water, so I had exactly 1 and a half liter to last me the whole race. By the end of lap 2, my base layer and mid layers were completely soaked. A quick stop inside the tent and the race doctor highly recommended that I change right away to a dry spare to avoid the freezing process which leads to hypothermia. I proceeded to change, fully knowing that this was my only spare change of clothes and I was only starting lap 3 of 12, I was in trouble. By the end of loop 3 (6.8 miles), I could feel another issue presenting itself with my socks, which were now completely wet. I immediately changed them, but I began to notice that my toes were really hard and numb to the touch. My strategy was to slow down in the hopes of slowing down my perspiration, but it did not seem to work, as by the end of lap 4 I was completely wet again from top to bottom. I needed to stop into my tent again and change into my last pair of socks and venture out. By this time, the course was completely soft and every step consisted of digging your foot in and out of the snow which required a tremendous amount of energy, all while drenching my last pair of wool socks. Lap 5 and 6 my body began to drop in temperature, as it had been over one hour in completely wet clothes in -30 degrees. By then end of lap 6 I was half way done (13.2 miles) in about 3 hours and 40 minutes which was a decent time, but with no more clothes to change into and a half marathon to go, I was in serious trouble. I walk into the tent to talk with the Dr. and notice one other runner on a stretcher shivering as I have never seen someone shiver before, the doctor said that he had a temperature of 30 celsius (86 degrees) and full on hypothermia, his body had collapsed. I felt my clothes and noticed that they were just about frozen and could feel my body temperature dropping, if I did another lap on them, I would be next on the stretcher, I had a choice to make. I could either stop right there and quit and collect a half marathon medal since I had done the distance (this was what some other runners had to do) or find a way to finish the race without getting hypothermia. To add insult to injury, my right foot was abnormally numbed. I took my shoes and socks off and noticed that two of my toes were completely white, frostnip, which basically meant another lap and frostbite would most have likely set in. If I was to finish the race, there was only one alternative left: get my body warm and keep it warm for the rest of the race. I went to my tent took my wet clothes off and changed into my polar clothes. That meant my polar jacket, ski pants and my 5 pound polar boots. I knew that I was not going to be able to run, but I would be finishing this marathon even if I had to walk the rest of the way. On my way out of the tent one runner asked me what I was doing and told him that I was going to walk in these clothes. He pointed that I was sure to overheat and that my boots were way too heavy to do 13 miles on. I marched on. By the end of lap 7 (15.4 miles), it felt like a sauna inside my body. The only advantage to using these clothes was that the cold was not able to penetrate inside and even though I was drenched, I kept warm, the big disadvantage was that I was getting very dehydrated. By the end of lap 8 (17.6 miles) I ran out of water. I had 4 more laps to go which at the pace that I was going would take me over 3 hours to complete. I kept going. By this time the course was nothing but soft deep snow and every step with my 5 pound boots a real struggle. By the end of loop 9 (19.8 miles) I could feel the blisters on my feet, pain in every step. I went into the tent and asked for some water from my fellow runners and I get a sip here and there, but not wanting to take too much as everyone has a limited supply. 3 laps to go…. On lap 10 (22 miles) I get stopped by one of the guards patrolling the area for polar bear saying that my face was becoming too white and needed to be covered. I was sweating so much that the only relief that I had was in the form of cold to my face, but with the bitter cold it was causing it to burn. It felt ironic that I am in the north pole and feeling like I would pass out from the heat, but I could not open my jacket as it would mean that cold air would set in and my sweat would freeze. Lap number 11 (24.2 miles) was a real blur, I really struggled here, it almost felt like I was going backwards and the lap would never end. Since there were only 48 runners, in parts of the course you would look around and see nothing but snow and ice, I felt helpless. Somehow, I managed to finish the lap, one more to go. On the last lap I get some energy out of nowhere, I think it was a combination of thinking about my family and all their support, knowing that I only had one more push before raising the Argentina flag across the finish line and realizing that even though I could have quit multiple times I kept on going. End of lap 12 (26.2 miles), total and utter elation.