A swim in the sea is not just for Christmas ...

Northern Ireland’s coastlines are dotted with swimmers who go out no matter what the weather or temperature.

It is a trend that is growing across the UK, with membership of the Outdoor Swimming Society up from 300 in 2006 to 25,000 in 2016.

Cold water plunges are believed to have health benefits, including strengthening the nervous system.

While some swimmers don wetsuits, a growing number of groups insist on “skins only”, ie swimming suits.

The Donaghadee Chunky Dunkers in Co Down is one of the longest running groups in Northern Ireland. It includes younger and older swimmers, male and female, with a range of abilities who swim every day come rain, hail or snow.

Martin Strain said the group has been going informally for eight years but has grown notably in the last three. He said cold water plunges help members who have mental health issues.

In Bangor, the Brompton Belles and Beaux have a core who swim every day at 8am. Marie-Therese Davis-Hanson started the group in 2017 and said numbers have rocketed.

One of the newest groups is Team Dash and Splash, whose members run along the coast before a plunge at Pickie Beach, Bangor on Sunday morning.

Member and former Olympic swimmer Andrew Bree said it has been a big change from the warm indoor pools of his competitive career.

“The water temperature gets down to around four/five degrees in February and March here,” he said.

“I got injured in 2012 and left the sport not the way I wanted to and I think that affected me, but now I have found that love for the water again.

“It strips the ego, when you get into the cold, there is no room for the past, there is no room for thoughts, you are focused on the present moment.

“My benefit was definitely mental, but there has also been a cardiovascular benefit, I have taken up more running and things I didn’t use to do. I come from a swimming background but I never liked running.

“I think it’s from the cold, you are pumping that blood through the body, I just feel overall really good from it.”

Dash and Splash founder Scott Riley said it started with a Facebook post in October 2017.

“I was going for a run and sea swim anyway, I got really interested in the health benefits of cold water and I was training to become a Wim Hof method instructor at that time which is a breathing and cold training technique for strengthening the nervous system,” he said.

“The first week, 15 people turned up. It has grown and grown ever since. Even in January/February there were 20-30 people turning up each week.

“At our anniversary swim in October we had 70 people taking part.

“There seems to be a push towards more outdoor activity, I think people intuitively know that it’s good for them, and maybe a societal shift where back in the day kids used to go out and get involved in nature, then computers came along and people got more indoor-oriented, but now the pendulum is shifting back and people are realising that getting outdoors makes you happier, healthier and stronger.”