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When did you last see a polar bear? On a trip to a zoo， perhaps? If you had attended a winteractivity in New York a few years ago， you would have seen a whole polar bear club． These" PolarBears" are people who meet frequently in winter to swim in freezing cold water． That day， the airtemperature was 3oC， and the water temperature was a bit higher． The members of the Polar BearClub at Coney Island， New York are usually about the age of 60． Members must satisfy two require-．~

ments． First， they must get along well with everyone else in the group． This is very important becausethere are so many different kinds of people in the club． Polar Bears must also agree to swim outdoorsat least twice a month from November through February．

Doctors do not agree about the medical effects of cold-water swimming． Some are worried aboutthe dangers of a condition in which the body" s temperature drops so low that finally the theart stops．Other doctors， however， point out that there is more danger of a heart attack during summer swimmingbecause the difference between the air temperature and water temperature is much greater in surmner thanin winter．

The Polar Bears themselves are satisfied with the benefits （or advantages）of cold-water swim-ming． They say that their favorite form. of exercise is very good for the circulatory system（循环系统）because it forces the blood to move fast to keep the body warm． Cold-water swimmers usually turnbright red after a few minutes in the water． A person who turns blue probably has a very poor circula-tory system and should not try cold-water swimming．

The main benefits （ or advantages） of cold-water swimming are probably mental． The Polar Bearslove to swim year-round; they find it fun and relaxing． As one 70-year-old woman says，" When I gointo the water， I pour my troubles into the ocean and let them float away． "

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