Visitors to Denmark are often surprised to learn that Danes leave their infants outside to sleep in the cold Nordic air. But it takes living here a little while to discover another peculiarity about Danes’ fondness for the cold: there are a lot of winter swimming clubs – and they have waiting lists.

According to one index, Denmark has 80 official winter swimming clubs, with a total of almost 20,000 registered winter swimmers.

At the Helgoland sea baths, 5km from Copenhagen’s city centre, a winter swimming club called Det Kolde Gys (The Cold Shiver) has been in operation since 1929. Today, it has more than 2,000 members and a waiting list.

Mary-Louise Sørensen, the club’s chairman, has been winter swimming for over a decade.

“I swim around 200 to 300 metres, but I’ve been training for that for quite a few years,” she said. “It’s not something you just do.”

As if swimming in ice cold water in winter were not enough, Sørensen’s preferred swimming hour is 6am – long before the winter sunrise in Denmark.

The natural sea currents at Helgoland make each winter morning swim unique, she said.

“There’s a lot of movement in the water here. So, one day we can have ice all over, the next day it will all be gone, and the following day it will be back again.”

Affordable and affable
A couple of years ago, the City Council opened Koralbadet (The Coral Pool), the third outdoor swimming pool in the city’s harbour. The other two harbour pools are at Kalvebod Brygge and Islands Brygge.

December’s an awfully strange time to open an outdoor pool in Scandinavia, you say? Well, Koralbadet has winter swimming and – luxury of luxuries – a sauna too.

“There’s a new mentality and the politicians were really supportive,” said Ulla-Britta Buch, the chairman of Badekompagniet Sluseholmen, the winter swimming club that convinced the city to build a sauna on Koralbadet and open the pool for winter swimming.

You have to be a member of Badekompagniet Sluseholmen to use Koralbadet in the winter, and there is, of course, a waiting list. But, like Det Kolde Gys, the price is a reasonable 500 kroner per year.

“I think that if this turns out to be a success, the city will be open to even more possibilities. Islands Brygge contacted us, because they want [winter swimming with a sauna] too,” Buch said.

Sørensen has also noticed increased interest in winter swimming.

“It has become more and more popular in the past few years. I think it’s because of the focus on health and the whole environment. Winter swimming is outdoors and it’s really healthy.”

Health benefits
According to Dr Jerk Langer, swimming or even just dipping into icy cold water invigorates the blood circulation, raises the metabolism, and flushes out toxins.

The cold shock also sends adrenalin and endorphins racing through the body, producing a feeling of well-being that lasts up to four hours after a cold plunge.

Langer admits that there isn’t a whole lot of scientific evidence to prove all of the health claims made about winter swimming, but devoted winter swimmers – himself included – swear by it.

A few studies have indicated that winter swimming reduces pain and discomfort among arthritis sufferers and boosts the body’s anti-oxidative protection, which could make it more resilient to environmental stress, disease and ageing.

“I don’t know if winter swimming makes you healthy or if it’s just that healthy people are the ones who winter swim. I guess that’s a chicken and egg thing. But I do know that it makes you a little proud of yourself. It’s become a part of my personality that I never knew I had,” said Berrit Sidse Kvorning, a Badekompagniet Sluseholmen member.

Can’t stop now
A few years ago, a friend who winter swims invited Kvorning to the beach in January and challenged her to dive in. She did and hasn’t stopped since.

“When you dip in it’s a gorgeous shock! It’s simply a celebration of ice cold water.”

Still, Kvorning sometimes needs to remind herself that the water can only get so cold.

“Sea water can never be less than -2°C, otherwise it’s ice. So, if it’s fluid, you know that it’s not colder that -2°. If you remember that, you can go in easily,” she said. “And with the sauna, it’s a piece of cake.”

Partway into an unusually warm winter, swimmers all over Denmark will be hard-pressed to find any ice chunks – and they may not even need that sauna. With water temperatures at Helgoland and Koralbadet still between 3-4 °C, is it too warm to winter swim?

“Noooo, it’s wonderful!” said Buch. “I was just in this morning, and it was so nice.”

Winter swimming resources

Det Kolde Gys
Badekompagniet Sluseholmen
Find a winter swimming club near you