Reply #7: Here's a bit on that

[muriel_volestrangler]

Most people who attempted such a feat would drown within minutes as the intense cold disabled their muscles. Mr Pugh believes that he can raise his normal body temperature by one degree by concentrating on raising his heart rate.

Tim Noakes, of Cape Town University, an expert on the effects of cold water on the human body, monitored the swim and found that on leaving the water Mr Pugh’s body temperature had dropped to 36.5C. Twenty minutes later it had fallen even further to a dangerously low 35C, but within an hour it had recovered to a normal 37C.
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Mr Pugh holds the record for the world’s most southerly swim, on the edge of the Antarctic ice sheet, and last year became the first person to swim the length of the Thames. He claims to be the only person to have completed a long-distance swim in each of the world’s five oceans.

He has already attracted the nickname “Polar Bear” for his cold-water swimming. He trained for his latest feat by eating five meals a day for three months and putting on 24 lb. Mr Pugh reached the Geographic North Pole by hitching a lift on an icebreaking ship sailing out of Murmansk in northern Russia.

http://www.timesonline.co.uk/tol/news/uk/article2080612.ece