Cold water swimming really does make you feel happy, brain studies show

Bathing in cold water triggers specific changes in the brain that cause people to feel more upbeat and alert, according to a new study.

MRI scans taken shortly after cold water immersion reveal changes in the connectivity between the parts of the brain that process emotions.

A team of researchers from Bournemouth University tracked the changes taking place in different parts of the brain in 33 volunteers who were immersed in a pool of water of 20C for five minutes. During this time, an ECG and respiratory equipment measured their bodies’ physiological responses.

Participants were then given a second fMRI scan so the team could look for any changes in their brains’ activity.

Dr Ala Yankouskaya, a senior lecturer in psychology at Bournemouth University who led the study, said: “All tiny parts of brain are connected to each other in a certain pattern when we carry out activities in our day to day lives, so the brain works as a whole.

“After our participants went in the cold water, we saw the physiological effects – such as shivering and heavy breathing. The MRI scans then showed us how the brain rewires its connectivity to help the person cope with the shock.”

Comparing the scans showed that changes had occurred between the medial prefontal cortex and the paretial cortex – two parts of the brain that control emotions, help humans to stay alert and make decisions.

Dr Yankouskaya continued: “So when the participants told us that they felt more alert, excited and generally better after their cold bath, we expected to see changes to the connectivity between those parts. And that is exactly what we found.”

Health experts have long recommended the benefits of cold water immersion, but no previous research has examined its impact on the brain. Exposure to extremely cold water can raise levels of endorphins and improve circulation and cognitive function, according to various studies.

The team are now planning to use their findings to understand more about the wiring and interactions between parts of the brain for people with mental health conditions.

“The medial prefrontal cortex and parietal cortex have different wiring when people have conditions such as depression and anxiety,” Dr Yankouskaya explained.

“Learning how cold water can rewire these parts of the brain could help us understand why the connectivity is so different for people with these conditions, and hopefully, in the long-term, lead to alternative treatments.”

The study was published on Monday in the journal Biology.