However, a startling fact was discovered by the researchers from the University of Iceland: Guðlaugur’s fat is almost like seal fat. It is more solid and two or three times thicker than human fat.
This is very size and speed dependent, but increased viscosity delays separation and can actually reduce drag [1], [2]. In any case, the viscosity difference is not huge and water temperature is normally not precisely controlled for swimming events.
"Most people [...] suffer from vasodilation in extreme cold."
Only when the core is doing well [3], the opposite (vasoconstriction) occurs otherwise.
[1] http://jeb.biologists.org/cgi/content/abstract/204/1/81
[2] http://www3.interscience.wiley.com/journal/120798746/abstrac...
It turns a research group at UMN actually was crazy enough to do the test - it looks like the effects balance for a human swimmer.
http://it.umn.edu/news/inventing/2004_Winter/goingforthegoo....
It's easier to maintain momentum and glide in cold water, whereas swimming in warm water feels like you're swimming in molasses.
Also, as my body heats up, cold water feels more cooling, obviously.
I'm curious what should I do if I fall into cold water: should I really take my clothes off or not? The first option sounds a bit counter intuitive to me.
By the way, how can people swim in jeans or other clothes? I find it very hard, it's like dragging some weights.
They don't provide insulation, and only serve to make you wet and extract heat from you. Just like a wet towel wrapped around a champaign bottle.
Once someone is out the water wet clothing should be removed.
New cold water will seep through much faster than your body can warm it. Even if you gained a fraction of a degree from tightly fitting clothes you'd lose much more than that through lack of mobility.
See: http://en.wikipedia.org/wiki/Wetsuit
". . .a thin layer of trapped water could be tolerated between the suit fabric and the skin, so long as insulation was present in the fabric in the form of trapped bubbles. In this case, the water would quickly reach skin temperature and the air in the fabric would continue to act as the thermal insulation to keep it that way. The suit did not need to be dry to be insulative."
The idea behind their operation is that you have a thin film of warm water around your body, isolated by a waterproof neophrene layer. So there's: The Sea -> neophrene -> Warm water that doesn't freely mix with the sea -> You.
That doesn't work (as deadmansshoes thought) if you're wearing normal clothes instead of a neophrene layer. In that case the water next to your body is constantly being replaced by new & cold water, faster than you can heat it up to provide you with insulation.
Both wetsuit and drysuits depend on there being a layer next to your body that you heat up. With wetsuits this is a layer of water that doesn't get swapped out, with drysuits it's a layer of air + rubber.
The article suggests you won't be able to swim so struggling to take your clothes off seems like very bad advice.
Several layers of clothes, and even a semi-waterproof jacket or anorak will trap water - and air which would help with bouyancy.
A fraction of a degree could be all important - there is a tipping point where a fraction means living or dying.
I'm impressed. That guy must be so fit.
His descriptions are chilling. "When the ship sank from underneath us and we were submerged for the second time we decided [the three of us] to swim. We decided not to help each other which would have been hopeless. We spotted the lighthouse and started swimming towards it. Soon there was only the two of us left calling between us, but soon enough I stopped hearing any calls."
More amazingness: On his way to shore a ship came within 100m of him. He spoke to "múkki" an imagined sailor's friend on the way, told himself jokes and said some prayers. When he came to shore he had to hold onto a rock wall while waiting for the tide to recede. While walking he spotted a bathtub used for lifestock feeding he punched through a layer of ice to get drinking water.