The science behind Boxing Day and New Year dips which keep people coming back

The Christmas period is a time of giving – whether that’s buying gifts for your nearest and dearest, or donating or volunteering for charity.But far from chucking spare change into the nearest Salvation Army donation tin or spending some time at the local food bank, some people choose to fling themselves into the freezing cold sea.Boxing Day and New Year’s Day dips are growing in popularity, with more and more people – often clad in Santa hats, reindeer antlers or snowman