By: Blonde Two

The UK winter outdoor swimming season starts in November and goes on to the end of March. Which is partly why, on November 1st this year, I decided to conduct some (admittedly amateur) research into the impact of cold water swimming on the human body… well on my body, which is human but not the same as anybody else’s. Convinced that outdoor swimming is helping me to stave off some of the more irritating symptoms of being in my 50s, I decided to record the impact of my chilly early morning swims on my mental and physical health.

Of course, research is supposed to be scientific, and a copywriter in Devon who is already convinced of something is unlikely to be as unbiased as say, a scientist who has never swum in cold water. She is also unlikely to be as good at setting up a sensible spreadsheet to record her results. Nonetheless, I have enjoyed the experience and will continue. Here’s what I have found out so far:

I didn’t swim every day…

During November I swam in the sea for 13 out of 17 days. A fair proportion of the non-swimming days were because the sea was too rough but I did notice that I didn’t always make up for lack of exercise on those days.

Outdoor swimming appeared to have more impact on my physical health than my mental health…

I scored my physical and mental health out of ten at the start and end of each day then used these to calculate an ‘effect’ factor.

Physical health average ‘effect’ score

Swimming days – plus 0.8

Non-swimming days – minus 0.4

Mental health average ‘effect’ score

Swimming days – plus 0.7

Non-swimming days – zero

Alternative or additional exercise had an interesting impact…

Despite perhaps not indulging in enough alternative exercise, I noticed that while long walks left me feeling mentally strong, they didn’t have as positive an impact on my physical health (usually my knees).

Other factors had an impact…

  1. When I hadn’t swum for three days I noticed an increase in mental health impact when I returned to the water.
  2. Colder and longer swims appeared to score more highly than shorter, warmer ones.
  3. Swims with at least three other swimmers appeared to score more highly than less social ones.

All those years I spent teaching people to use spreadsheets weren’t wasted…

Well they weren’t wasted on me. Thank goodness there isn’t research around to investigate how many of the hundreds of youngsters I taught to use a spreadsheet have found the information useful since then…


So there you go. Not scientific cold water swimming research by any means but interesting nonetheless. I would be interested to hear from anyone who has done something similar… Or is finding that cold water swimming appears to be exactly what they need to get them through the winter.