Physical fitness is always important – and even in these dark, cold days of winter, it’s good to keep moving.

This week, one workout stood out in particular – courtesy of Barton Williams, a Chicagoan taking the “cold plunge” to an entirely level.

Barton Williams lives in the same building as CBS 2’s Joe Donlon in Streeterville – and got Donlon himself swimming in Lake Michigan. But unlike Donlon, Williams swims in Lake Michigan in the frigid depths of January – equipped only with a hammer and a rope, and wearing no wet suit.

See CBS Chicago