It started as a summer ritual. After my morning workout I would get into the pool for a cool down swim. During the hot months, when the pool was far from freezing and I was boiling, getting in and staying in was easy. I’d happily spend 20-30 minutes swimming laps. As the weather cooled and with it the pool, those swims got shorter; but by then it had become a habit. Getting into the pool during a week of relentless rain and on chilly mornings suddenly didn’t seem impossible, and so I continued. It is now mid-April, the water is icy, and for the first time since I can remember, I am still swimming… or polar plunging as I now call it.
While Winter is certainly not here, the temperatures have gone down especially in the morning, which now has that distinct wintery chill. The pool, unheated and largely shaded has become decidedly icier and icier. While it may not be Whim Hoff levels of cold, I’ve always been a fair-weather swimmer who needed warm weather and sunny days to get into the pool. To still be swimming feels like an accomplishment and is most definitely cold-water swimming.
I am becoming a cold-water swimmer. I have found the magic of immersing yourself in water. It makes you gasp, your bones hurt and gives you head freeze. It might sound less than enticing, but I must share its wonders.
Getting in is the hardest part, it is cold and uncomfortable and oftentimes reminds me of how I felt during a Cryotherapy session last year. Once you’re in, you actually need to start swimming and those first two laps are the worst. You’re cold, your skin burns, and your body has tensed up which makes moving slow. But if you push past that and completely immerse yourself, ice headache and all, it becomes magical. Your body adapts to the cold, everything else falls away and your mind clears. The cold begins to feel good; and the movement peaceful, calm and refreshing.
In his book The Stress Code, Richard Sutton explains the stress reducing effects of swimming. Swimming activates the Vagus Nerve and reduces activity of the stress axis through a survival response called ‘the dive reflex’. When you swim underwater for more than 10-15 seconds those post-session stress reduction effects are amplified (not to mention swimming underwater for as long as you can hold your breath is exhausting, invigorating and blissfully quiet). This is because no matter what biological state you are in, when you submerge yourself in water, the brain’s first response is to stop breathing and slow down your biological processes.
Initially, however, he explains, submergence in water triggers a flight or fight reaction. It slightly raises arterial pressure as blood and lung oxygen stores are preferentially redistributed to the heart and the brain. What follows this reaction is a strong vagal presence and corresponding calming of your biological state through two mechanisms: baroreflex activation from the rise in blood pressure and chemical receptor stimulation that occurs as oxygen levels decline during the latter part of a breath hold. Studies have shown that swimming underwater can reduce heart rate by more than 50%.
When you swim in cold water, vagal activity is further amplified. The reason, Sutton explains, is that cold water contact in and around the forehead, eye and mouth is a strong stimulus for the fifth cranial nerve, the Trigeminal Nerve, which activates the Vagus Nerve. The aerobic nature of swimming, combined with the rhythmic breathing that accompanies this activity adds an additional dimension to the stress-reduction equation. The more you stimulate the Vagus Nerve (be it with breath work, swimming or cold water face immersion) the greater your resilience will be during emotionally and physically stressful events and being able to manage chronic stress.
Nike master trainer Joe Holder explains that when you are immersed in cold water, your body reacts like you’re lost at sea (fight or flight). Controlled, safe doses of that biological panic response can have real benefits. ‘They can reset things so that your survival instinct isn’t as likely to be triggered when you don’t want it to be. It teaches you to work through discomfort and handle small daily stressors better.’
Aside from the stress management and resiliency benefits of cold-water swimming, there are a host of other health benefits. Cold water swimming is linked to pain relief, improved moods, longevity, improved sleep, reduced inflammation as well as helping with anxiety and depression.
Swimming also strengthens your lungs. As explained by David Tanner, Phd, ‘You breathe in quickly and deeply, and then let the air trickle out. Because your head is underwater when you swim, these breathing adjustments are vital, and they may improve the strength of your respiratory muscles. This kind of breathing keeps the lung alveoli—the millions of little balloon-like structures that inflate and deflate as you breathe—from collapsing and sticking together.’
You can choose to swim in a heated pool, and still yield the benefits of swimming. Or opt for a 60 second ice cold shower to yield the benefits of cold-water face immersion. But if you can, combine the two so you not only get the benefits of swimming, but also of cold-water immersion.
For me combining the two makes it more enjoyable. I have never been able to willingly endure a cold shower. The closest I’ve gotten to the practice of starting your day with an ice-cold shower is enduring those painful seconds before the water heats up to my preferred temperature of scalding hot. Showers should be hot; but as I am learning, swims can be ice cold and leave you invigorated. They’ve become my favorite way to end a workout and start the day and without doubt have made me calmer… But maybe speak to me in June when winter is in full swing to see if I’m still singing the same tune.
Zissy is the co-founder of Nutreats. She likes to make things, do things and wear things.