Saturday 13 April 2013

a week is a long time in ice swimming

 I don't know if you are like me and apt to commit to a bold course of action without knowing what it really entails. Call it tempting providence. 

I'm not sure why providence has to be quite so mischievous, or what it has against me. Each time I do it, it draws me into a process that stretches me out of shape. The stakes seem to escalate as soon as I open my mouth, or a wild idea has occurred to me. 

I usually come out of it glad that I did it.

This winter, ice swimming has been a bit like that. 

When I decided I would train outside for the whole winter, the water temperature dropped by 4 degrees in as many days.

Rather than eat my words, I thought I'd test the truth of them. On Dec 19th I swam my first Ice Mile, 1,708m at 4C in the lido.

In the back of my mind I had a  fantasy about swimming 7 ice miles in 7 days. However, that first one took the wind out of my sails and for a few days I could hardly bring myself even to look at the cold water.

Recovery and getting your core temperature up as quickly and safely as possible afterwards are crucial for a couple of reasons. The first is because when you get in cold water, there is a constant process of heat transfer from your body to the water and vice versa (this is known as the Zeroth Law of Thermodynamics... yawn). The third law is important too, because it is about heat added to a system and how that affects the rate of heat loss in the form of entropy. If you get cold enough, your whole system shuts down and you die.

To learn more about how the laws of thermodynamics impact OW swimming and particularly cold water swimming, please grab hold of me at a party or function and we can bore the daylights out of each other. Or type "Laws of Thermodynamics" into any search engine and bore yourself in the comfort of your own home.

 I'll talk more later about a couple of little things you can do, that do make a difference.

The second reason is that when you get into cold water, the blood is squeezed from the extremities into the core, starting with the smallest and most distant, such as toes and fingers, then wrists ankles knees arms thighs and finally the head.

This is the body's attempt to conserve more heat for longer. This vasoconstriction causes the blood pressure to rise. Getting out afterwards and the subsequent drop in blood pressure is the riskiest time for the heart.

First up is postural hypotension, going from a prone to an erect position. As suggestive as that sounds, sadly I am only referring to standing up after the swim.

A brief sit down slows the drop and reduces dizziness.

Having a hot shower after a cold swim causes cold blood to rush back into the core and the pressure to go down sharply as the blood vessels expand at the extremities. Lifeguards at the Lido say this is the time when people most commonly pass out. I stopped having a shower straight after very cold swims months ago and it has made a massive difference to the ease and speed of my recovery.

Roughly 15 minutes after you finish swimming you experience the 'afterdrop'. This is when the cold blood naturally finds its way back into the core and you start to feel really cold inside. And the shivering reflex is initiated. If you have any sense, by now you are wearing a woolly hat and have as many layers of dry natural fibres on as possible and are gently walking to warm up from the inside out.

I wish my friend Philip Hodges, who (sometimes) loves cold water and, as far as I know, always loves things statistical and/ or graphical could take all the figures I wrote down this winter and make them into a really brilliant chart or graph and plot some trends or something. Save me boring you even more than I have already.
 
Part of the reason I haven't asked him to or fed him the raw data is that I imagine he would bemoan my failure to record wind speed and air temperatures and say something like, "John, I could make you a graph or diagram, but quite frankly mate, it would be inconclusive at best, and at worst, a load of bollocks."

For three weeks the temperature went up to 7 and 8C. I pushed my distances up and was swimming over 2.5k each day by the end of that period.

On Sunday, Jan14th I swam my second ice mile, 2,074m at 5C. The next day I swam 1,952m at 4C. Emboldened by my success, (some would say getting really cocky) I made another one of those rash decisions I mentioned before.

I thought (out loud to a few friends) that I would swim 7 ice miles in 7 days (after all I had already done two, how hard could it be?). It was as if I had slapped nature around the face with a frosty gauntlet.

And nature responded in kind. The next day it was 3.5C in the water, I swam 1.830m. The wind switched to easterly and it was -6C that night. I scraped 1,637m at 3C and it was the most chilling and hardest so far with the heavy frost and biting 10mph wind.

The recovery and after drop was totally brutal that day. If I had been looking for my limit earlier in the season, that day I felt as though I had found it. I knew I needed something extra if I was going to do it another 3 days running.

Next morning the water was down to 2C. I wore two woolly hats, two pairs of wool socks, two pairs of merino wool thermals, tracksuit trousers, long sleeved thermal top, t shirt, cashmere jumper, thick lambs wool jumper, a hoody and a goose down jacket. I jogged 4 or 5 laps around the lido before I got changed.

The pool area was dry when I got in, by the time I completed 28 lengths/ 1,708m, there were two or three inches of snow covering everything. It was a magical experience I won't forget for a while. The snow took my mind off the cold and the pre swim warm up had enabled me to swim further than the day before and at a lower temperature. I got dressed and ran around the pool to warm up.

Saturday was a low 2C. A photographer asked if he could take pictures for an article in a French magazine. To see him crouching or lying in the snow at one end of the pool for my entire 28 length swim kept me amused. I tried to pull my grimmest and most heroic face as I surfaced to make my turns. Note to ice swimmers- ego trips can and do keep you warmer. As if that wasn't enough, an audience had gathered that day in the entrance to the changing rooms to cheer me home.

All this was in a stark contrast to Sunday. I was totally alone in the lido. No press. No people to impress. I didn't look at the thermometer on the way in. Just warmed up, got changed and got in. Nothing could have convinced me to swim more than the 27 lengths that made up the mile to pick up my towel and flip flops from where I'd left them when I got in.  Greg the lifeguard told me the water was 1C as I left.

7 ice miles in 7 days.... it's as easy as that.

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