Over 400 swimming enthusiasts from Tianjin and Beijing take part in a winter swim in Beichen District of the Tianjin Municipality in north China (© KeystoneUSA-ZUMA/Rex Features)

More than 400 swimmers participated in a winter swim in north China.

A man does push-ups in minus 20 degrees celsius weather to warm himself up before swimming in an icy lake in Shenyang, Liaoning Province, China (© KeystoneUSA-ZUMA/Rex Features)

It's -4 F (-20 C) at this icy lake in Liaoning Province, China.

A winter swimmer moves floating ice at minus 20 degrees celsius in Shenyang, Liaoning Province, China (© KeystoneUSA-ZUMA/Rex Features)

Here's a swimmer moving ice at that same lake.

A brave swimmer takes a dip in the cold waters of the North Sea in the annual Boxing Day dip at Redcar in Cleveland, England. (© London News Pictures/Rex Features)

This woman is enjoying (?) a Boxing Day dip in the cold waters of the North Sea in Cleveland, England.

A swimmer gestures as he gets out of the Vltava river after the annual Christmas winter swimming competition in Prague, Czech Republic (© David W Cerny/Newscom/Reuters)

The Vltava River in Prague is the site of this annual Christmas swimming competition.

With water temperatures of 4 degrees, swimmers take part in the countries oldest Christmas swimming event the 66th Alfred Nikodem Memorial Winter Swim in the Vltava river in Prague, Czech Republic (© Eduard Erben/isifa/Getty Images)

The event in Prague is reputed to be the world's oldest winter swim. This was its 66th year.

Citizens of Split, next to the Adriatic sea in Croatia, enjoy the winter conditions by playing a game called "picigin" (something like volleyball) & skiing around town (© Tom Dubravec/Cropix/SIPA/Rex Features)

A man of questionable intelligence plays a form of water volleyball in Split, Croatia, while a more sensible woman skis.

A woman swims amongst ice in the freezing Nanhu Lake in Changchun, Jilin Province, China where it was minus 22 degrees Celsius (© HAP/Quirky China News/Rex Features)

A woman in Nanhu Lake in Changchun, Jilin Province, China, where it was nearly -8 F (-22 C).

Barmy locals in Harbin, China go for a quick dip in an icy outdoor swimming pool kept just above freezing throughout the winter months (© WENN)

This pool in Harbin, China, is kept just above freezing throughout the winter months.

A man enjoys ice swimming in a freezing mid winter river in Russia (© WENN.com)

What is that Russian man doing? Looks like the butterfly stroke.

A dressed up winter swimmer jumps into the cold water during an ice swimming session in Lanke, north of Berlin, Germany (© Johannes Eisele/AFP/Getty Images)

This jumper's in Lanke, north of Berlin, Germany.

A swimmer prepares a hole in the icy surface of a lake for the traditional ice swimming session in Lanke, north of Berlin, Germany (© Johannes Eisele/AFP/Getty Images)

It wasn't easy finding the water at Lanke.

Russian winter swimming enthusiasts swim before voting for the presidential election in the Russian Siberian city of Novosibirsk (© Ilnar Salakhiev/AP Photo)

These Russian winter swimmers took a dip before voting in the Siberian city of Novosibirsk.

Members of the "Krepysh" winter swimming club rub snow on each other after bathing in the Yenisei River, where the air temperature is about -1 degree Celsius, in Russia's Siberian city of Krasnoyarsk (© Ilya Naymushin/Newscom/Reuters)

These are bikini-clad members of Siberia's "Krepysh" winter swimming club. They rub snow on each other after bathing in the Yenisei River in Krasnoyarsk, Siberia.

Lyubov Valiyeva, a member of the "Cryophil" winter swimming club, plays with the snow by the bank of the Yenisei River in the Siberian city of Krasnoyarsk. The air temperature is -13 F (-25 C).

These 15 pics of winter swims are guaranteed to give you goosebumps

12/29/2012

Once a year, right around this time, perfectly intelligent people who usually try to avoid falling in frozen water do exactly that ... on purpose. All over the world, from Canada to the Netherlands to right here in the good old U.S. of A, people suddenly get the urge to jump into frozen lakes, rivers and oceans. We're not sure what would compel someone to do this, but just in case you ever wanted to get inspired to do a polar bear plunge, here are 15 photos from the past week for you.

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