Well, they would if you're a complete loon or you display masochistic tendencies.
Next Saturday (20th December) marks the date for this year's aptly-named Mad Midwinter Swim at Brockwell Lido, near Brixton. Organisers want to see 100 intrepid men and women give the chilly dip a go this year. All you need? Your speedos and, er, a hat.
The lido is officially this Londonista's favourite in our fair city (recently modernised; in one of London's greatest and least-known parks; fab atmosphere; ace in the Summer). And yet the thought of dive-bombing into water predicted to be even cooler than last year's bone-freezing, 'acorn-making' 3.2 degrees celsius fills us with nothing but dread.
In fact, it's still almost as soul-sapping as being made to watch the full length of the video for what is officially the most dreadful pop single in history. We spotted what looks very much like Brockwell lido in the background. Even remixing the whole thing to within an inch of its life only helps a bit...
Details of the swim at brockwell-lido.com.
Brockwell Lido pic in warmer time of year from ladelentes' flickrstream