Okay, you learned that in elemantary school.
98.6 - 52= 46.6 degrees difference. You think you want feel that?
The normal body reacts to cold by shunting blood to the vital organs and away from the limbs and extremeties. Your extremeties become hypoxic(lack of o2) and lose strength. You wont be able to swim distances that in normal conditions would be a cinch for you. It makes righting your body a feat of greatness, and getting back on it any tougher. Keep in mind the fact that once your core temp stops dropping, unconciousness follows quickly. People live being submersed because respiratory and cardiac function are depressed, the body shuts down, and sometimes can be brought back without any deficits. Not any fun though.
Do what you can to Prepare.
Sail safe and warm,
David Mosley
www.seacats.org