and..... I f%@ked the translation up and don't know the correct name in Dutch >_<
basically your body goes on lock down before you die and as a result no water will be able to get into your longs and as your heartbeat goes slower and all your muscles stop with being able to do anything you use less energy together with the fact that this only happens when its cold enough for water to freeze means you can stay under water for a very long time without too much damage to your body.
You are basically in coma before you die from drowning. Safes a lot of pain from water getting in your lungs and you can stay underwater longer but need special treatment to get out because your brain will not get enough oxygen and the only thing that keeps you from getting brain damage is the fact that your body is cold.
To get out of it your body needs to warm up but then you get brain damage and as a result it needs to go in a special way, warm blood with enough oxygen needs to be pumped into your body and the cold blood out.
get it or don't get it