Cold Acclimatization

It may not seem a whole great deal but since late September the sea temperature has fallen steadily from 18°C to exactly 12.0°C whilst standing in the shallows of St Mary’s Bay today.  Six degrees, what is 6 degrees?  Well if you are in the open sea 6 degrees is the difference between swimming a mile and a half over about an hour and arriving back at the beach still feeling functional and cutting that to just a mile and 40 minutes and beginning to shiver uncontrollably as you get dried and dressed.  This is of course wearing nothing more than swimwear and a pair of goggles.

Irrespective of the wisdom of swimming any distance when the sea is only 12C the question is nevertheless ‘what can be done to prepare for swimming under such conditions?’ because I will keep swimming and it will get colder yet.

Clearly keep swimming and track the seasonal change in water temperature is a good place to start.  This may debatably induce physiological changes but it certainly induces mental changes and a preparedness that ‘it will be cold but I am expecting that’.

There is a further school of thought that advocates cold showers, 10 minutes a day.  I have always been skeptical about that.  How can 10 minutes a day in a cold shower compensate for the remaining 23 hours wrapped up in clothes etc. keeping warm?  That just doesn’t stack up surely you are acclimatizing to being warm.

For this to work surely you want to take the stereotypical postman approach and go around all day and in all weathers in a short sleeved shirt and shorts or skirt, it’s your choice.

The swim today from the beach in St Mary’s Bay out to Durl Rock in the lee shelter of Berry Head was close to idyllic.  For the most part the sea was flat calm with a lazy oily quality and only occasionally was it ruffled by the slight breeze.  And the sun poured down.

Wild Swimming
Wild Swimming

Close to high tide and the current flow was northwards in the open sea, but where it met the headland some flow was turned back into the bay.  Whilst this left me swimming into the current initially it did mean that the water sweeping in from the open sea was crystal clear almost to the surf line.  Of course at some point I reached the area where the current was being turned aside and here things get strange.  One moment I was swimming into the current, the next it was behind me and yet within 50m it had turned against me again and then it was pushing sideways at me and I could feel my legs swinging away to one side leaving me to swim crabwise towards the rock.  The first time I swam this way perhaps 8 years ago I was somewhat panicked by this sudden reversal as on that occasion it left me swimming head into a current as I neared the beach without seeming to be able to reach it.  Now I simply accept it and swim on.

Durl Rock stood proud against the blue sky but with a slightly bigger swell sloshing white water over the lower rocks.  On a very big spring tide almost the whole rock submerges hence the need to leave a pinnacle standing at the outer marker as an impromptu beacon.  Today the rock is submerged in gulls and as I finally reach a hand to slap the rock: ‘I was here!’, an oyster catcher breaks ranks and in an instant the sky is filled with a cloud of birds that return to wheel and scream above me.  I have evidently broken their reverie as they dog me on my return swim and now with the slight breeze behind me I push on at the fastest pace I can keep up.

The last 100m in to the beach brings with it a little tension.  As I set off a seal was bobbing away down the far end of the beach.  I am cautious of seals especially when the water is not too clear and now close to the beach there is more sand stirred in.  Seals bite, well they bite me, and once here one drew quite a dribble of blood from my ankle.  The seal may have moved on or may still be out of sight at the far end of the beach hidden in the glare of the sunshine, but I am soon wading through the slight surf with all my limbs still attached.

Wild Swimming
Wild Swimming

One mile almost to the inch and 40 minutes almost to the second (which is not too bad making allowance for bird watching and photo opportunities) and I am not feeling the least bit chilly, maybe I am acclimatizing.  However, the sun is off the beach now and the thermometer hovers at just 8C in the shade and is not making allowance for wind chill and there is quite a lot of that.  Acclimatized I may be but before I finally lift my bag onto my back I am shivering quite dramatically and very much look forward to the warming stomp down the beach and Jacob’s Ladder of steps to climb to get back to the car.

 

Wild Swimming Map: Devon & Cornwall

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Knowing When to Retreat (as climbers call it)

As I stood in the kitchen sipping coffee and watching the sunrise this morning it slowly dawned on me that I should have headed to the river on the way in to work. Instead I had fixed it in my head yesterday that I’d go the full distance around St Mary’s Bay in the sunshine at lunchtime.

Sunshine there was and it was warm and there was plenty of it with only a light if wickedly chill breeze exactly as forecast, a perfect swim day. The sea however had other ideas.

It should have been quite calm under the headland but instead it was a washing machine, not on full maximum spin, but on more of a ‘synthetics’ setting. However, after 20 minutes, which should have got me the full 1/2 mile out to the rock when in fact I had covered only half that distance, it was quite clear that this was not the day I had planned.

And after another 20 minutes spent getting back to the surf line I definitely knew I’d had a good workout even if I’d got nowhere.

Wild Swimming
Wild Swimming

 

Wild Swimming Map: Devon & Cornwall

Hats, Boots and Gloves

I read a post by someone the other day that said something to the effect of ‘it’s a really rough beach, all pebbles, and footwear is essential’.  Which is odd, as I swim at that same beach a lot and whilst it is pebbles they are all smooth.  When it comes to what is seen as necessary kit then some of it is highly personal and is about boosting self-confidence.

Thoughts at this time of year with the temperature falling turn inevitably to winter essentials.  I have never felt the need for any sort of footwear irrespective of temperature, duration or conditions underfoot (though on that score I have cut my feet so many times I think they are now mostly past it).

I do sometimes wear gloves but that’s not about temperature it is because of a long standing problem from broken bones in my hand which from time to time comes back to haunt me and means something like picking up a coffee cup is quite painful (I keep straws handy just in case) and the repeated push of water on my hand can be very painful, the gloves just give support, though actually, as today, strapping my thumb to my forefinger with a hair band does just as well if not better.

I will swim on as the temperature drops, managing about 30 minutes at 7-8°C before reaching for the wetsuit, but around our bit of coast that is about where the temperature bottoms out.  And I will continue to swim shorter times, much shorter times, without the wetsuit in the river which can get down to zero C.

Nevertheless it is personal preference but if you feel footwear and/or gloves and/or woolly hat and/or anything works for you then it works for you there is no universal right or wrong.

Wild Swimming Map: Devon & Cornwall

All Kinds of Crazy

For reasons that are not entirely clear to me I decided it would be a top idea to swim out to Thatcher Rock this morning.  It was a top idea, but with every kind of weather from full on sunshine to pelting rain and howling wind and a full rainbow.  By the time I’d circled the bay, been to the rock and got back I’d done nearly a mile.

Wild Swimming
Wild Swimming

 

 

Wild Swimming Map: Devon & Cornwall

When the Newness Wears off Goggles

I always, always take my goggles sea swimming (well unless it is just a little dip) because any number of times I have set off in flat calm water only to get where there is more current or wind or chop and trying to swim on with every wave filling my eyes with sea water is very wearing.  Whilst I try to look after my goggles it is inevitable that many hours and many miles of being in use will wear the newness off, most especially the anti-fog coating.  Trying to swim whilst not being able to see through fog or dazzling sunlight may if anything be worse than having salt water in the eyes.  No, actually on reflection it’s not.

The anti-fog coating will wear off no matter how carefully the goggles are cared for, but that does not then mean they are written off.

The solution of last minute desperation is to spit on the goggles then rinse, but generally spit is not in the least bit bacteria free and as a rule you probably wouldn’t spit in your eye.  It really is the last resort.

Now, you can buy, at a relatively huge cost, sprays which restore the anti-fog, but only for a single swim.

There is however a cheap and 100% effective alternative: baby shampoo.  One brand is Johnson’s No More Tears which is worth mentioning by name simply because it does exactly what it says on the label (or doesn’t do?  I’m confused, but it does not me cry anyway).  Just wipe the tiniest smear over the inside of the goggles with a fingertip and that’s it.  Don’t rinse, there is no need, the clue is in the name!

The principal is simple.  Scratches in the goggles allow tiny beads of water to ‘nucleate’ and so the goggles mist up.  The shampoo coats the imperfections and any water vapour dissolves into the soap leaving a perfect and most crucially, see through film.

After swimming, wash, dry and re-apply.  A branded spray may be as much as £5 / 20ml and is gone in no time.  Baby shampoo is £0.80 / 200ml and a single bottle will last a lifetime.  Unless of course you also use it to wash your hair (guilty as charged) but that is never going to work with anti-fog spray.

 

Wild Swimming Map: Devon & Cornwall

Cold Water Swimming

A good Article on Hypothermia appeared in my reading list recently.  The single most important point in this article is that hypothermia takes time a message I have been pushing for years.  However, time and again alarmist and misleading information is put about by reputable organizations up to and including the RNLI that suggests hypothermia can set in or kill you in just a few minutes.

As the article explains there is a gasp reflex (cold shock reflex) from sudden immersion in cold water (walk into a cold shower if you want to try this) and clearly if your face is underwater that can be almost instantly fatal.

Hypothermia takes time, though the exact time will vary with water temperature, alcohol consumption, natural body insulation, and simply how warm you are to start with.  Nevertheless as the article points out, long before full hypothermia sets in ability becomes impaired so that you may well be unable to make even a short swim back to safety.

Perhaps the most relevant part for cold water swimmers concerns the description of the ‘recovery’ stage.  It is all very well to say “wrap up, do not move, get warm”, but that is a luxury swimmers do not have.  Arriving back on river bank or beach the imperative is to get warm as quickly as possible because the immediate problem is ‘afterdrop’.

After the exertion of swimming for a few moments all seems well, but removed from the water the response of the body is to once more circulate blood from the core back to the extremities that have been experiencing reduced blood flow in order to retain heat in the core.  Now of course cold blood is circulating back into the core and the shivering and discomfort of afterdrop sets in.  There is perhaps barely time from exiting the water until shivering becomes so severe that it becomes a challenge to tie shoe laces.

This is the point at which following the advice in the article one would sit still, drink warm tea and wait the shivers out.  Some people do indeed go in for wrapping up in a swimming robe and/or hugging a hot water bottle or get in their car with the heater going.  My problem with the latter is that all the layers just put on are as effective at keeping warmth out as warmth in.  Besides recovering from the shivers can take an hour and who has that long to sit and warm up?  Whilst driving with the shivers would I imagine be as dangerous as driving whilst drunk.

Therefore there is little choice left in the matter; if sitting still is not an option then getting moving is not a choice it is the only option.  It is my preferred option.  I am not suggesting attempting a half marathon, not wearing all those clothes anyway, but a good stomp certainly gets the warming up process started.

Wild Swimming
Wild Swimming

For local swimmers here in Devon this is a timely discussion.  The temperature of the river water is down almost 5°C on just two weeks ago; 8.5°C yesterday afternoon in the sunshine but only 7.5°C this morning after the frost.  The sea temperature has also started to drop, though it has stayed unseasonably ‘warm’ through October it is now sliding down past 15°C and will probably reach 5-6°C by mid-February.  Meanwhile the river can get to minus figures.  People will keep on swimming though so it is important to separate fact from fiction and focus on the real dangers and not hypothermia which is simply a word most people recognize but few seem to understand.

Wild Swimming
Wild Swimming

 

 

Wild Swimming Map: Devon & Cornwall

The Non-Zero-Sum Game

There was frost on the car windscreen this morning, the first of the season, but otherwise it was a perfect clear sky morning without any breeze.  Honestly though after yesterday when it took several hours for me to warm through after swimming, why am I doing this again?

I must have been especially quiet getting changed on the river bank; where the water flowed by with barely a ripple and steamed with mist (Still Pool living up to its name again), because as I stepped into the water the otter that was sat 10 feet away on the bank obviously got its first hint that I was there. All I saw was the brown shape and sinuous tail sliding quickly into the water and then the trail of bubbles breaking the surface as it swam across the pool: classic!  Like a total amateur though I watched the bubble trail thinking it will have to come up soon, but of course it was swimming well ahead of the bubbles so I didn’t see it again.

Wild Swimming
Wild Swimming

Until now my aim has been whenever possible to do three times up and back which, depending on the flow of the river gives a distance of between 175m to 205m each way (402m = ¼ mile).  If the flow is less the distance is further as it is possible to start from the edge of the downstream shallows and get right up into the top end shallows.  However, as the flow increases the shallows flow too fast to swim but though the distance diminishes the effort to swim upstream increases to a tipping point where the river becomes and endless pool and distance is no longer an issue as swim as hard as you like you will go nowhere.

Clearly if the flow is slight and the water is warm (we are talking July) then I could swim up but float back and that would be a zero-sum game where all the added effort put in swimming against the current is wiped out by the free ride back making it equivalent to swimming in still water.  However at the endless pool end of the spectrum it is self evidently a non-zero-sum game as clearly if I go nowhere there is no free ride back to detract from the effort of swimming just to ‘stand’ still.  But then what about the points in between?

What I have determined from longer sea swims is that my pace is consistently 40m to 44m/ minute.  In the endless pool non-zero-sum game scenario in the river the pace is clearly zero meters / minute.  Let’s assume then that in the river I could swim at the same pace as in the open sea equivalent to the average of the above figures ie 42m / minute.  The assumption is however wrong on at least two grounds which are firstly with shallows and eddies it is not possible to get a steady pace as strokes get missed and secondly head on to a current stifles the stroke making it less efficient.  Consequently I will take the 40m / minute figure as my maximum river pace.

In the zero-sum scenario (swim up, float back) it stands to reason that over a given distance my pace should equate to 40m / minute.  Anything less than that moves me further into the non-zero-sum scenario to a maximum value where the pace is zero meters / minute.

Actually though what I have found is that even in summer the pace is around 35m / minute and today when the river flow is somewhere between summer and endless pool my pace is about 28m / minute.  Furthermore I estimate that when the river is flowing at the maximum rate where it is possible to actually swim upstream that pace drops to 25m / minute and I exit the water feeling very worked out.

Why, you are wondering, is there such a big gap between zero and 25m / minute?  It’s a fair point and in a perfect situation it should be a continuum, but the river flows faster and slower along the course depending on shallows or deeper water and where I set off to swim from the current is swiftest and so at all points between zero and 25 I simply cannot start swimming.  What I need is a uniform channel with variable flow, maybe some sort of pool perhaps?

And this is what keeps my mind off the fact that I am swimming in 8°C water at 7:30 in the morning where it feels as though my fingers and toes have fallen off.