Swimming Question of the Week - October 14, 2008

...for me the comfortable temperature of water for swimming is 25 degree celsius....but more importantly it will be nice if the ambient is more than 28 degree celsius....

-jagadish

Don't know about the too hot issue! It's a problem I'd like to have.

As for temp, I'm a Master's Open Water swimmer for the past 2 1/2 years here in Ireland.
Triathletes can wear a wetsuit if the temp is below 18 C (65 F).

I'm fairly light (under 12 stone, about 74 kg) for Open Water so I suffer from cold.

At 15 deg I can train for about 3 to 5 hours. At 14 that drops to 2 to 2 1/2 hours. At 13 it's down to an hour to an hour & a 1/2.
At 12 it's about an hour. At 11.5 it'll be 45 mins.

For checking I monitor my fingers. The times above are the times when my fingers are starting to spread or maybe just the little finger has "gone".
Yesterday I did 55 minutes at 12.5 and the little finger was gone (couldn't be closed). Warm up was fine, (dressed quickly), plenty of clothes and the heater in the car, took me about an hour and a half to get fully back to normal. Water was dead calm, sun in sky, no wind, meant my temp didn't drop rapidly after I got out of the water going back to the car AND I wasn't shivering. (You've got 4 to 5 mintues to get dressed if it's cold water and windy before your hands stop working and the shakes start.
All this is affected by sun in the sky (haven't had much of that here for the past 2 summers), the wind, and the sea conditions.

You could train longer once you're familiar with the experience and are used to cold, but I usually train to the point where the hand is just starting to go. If I train longer (and do more in the spring/early summer) I will get the Shivers after I get out. We're talking the real shivers here now, not goosebumps. The uncontrollable body-shakes, with the jaw clamping shut
Training at 14 degrees C and then moving to 16C in Dover this summer was a huge change.

For example I did an 8 mile tide assisted last year in Oct without wetsuit that took me 3 hours.
at 12 to 12 1/2 deg C. My fingers were spreading at 1 hour, I had warm drinks about every 45 minutes, but I was Mildly Hypothermic for 15 minutes after the finish. With help I was able to get dressed but I don't remember anything for those 15 mins. Lots of layers and warm drink to warm up. At 15 deg C this year I did a 5 hour swim in comfort with no warm drinks during the swim and no shivering after.

16C felt like the warm shower I have when I get home from sea training here, so for me and most swimmers here, 18d C and up means never having to worry about cold so you could swim up to your training goals, (6 to 12 hours).
Some people here are more resilient than me without extra weight, but if you want to do better in cold water, extra weight and plenty of cold water habituation/acclimatization help.
This winter I plan to keep swimming in the sea once a week as long as I can, even if they are only short dips. Water here (south coast) gets down to about 9 C (48F). At that I estimate 10 minutes, if I can do it.

So the long and the short of it for me is;
18C is heaven
16 is great
15 is good
14 is fine
13 C is cool
12 is cold
11 is colder
10 is too cold.

When I was growing up in St. Andrews, on the East Coast of Scotland, in the 1930s - there were no indoor swimming pools around, so we swam - in the summer - in the North Sea. My school had its own (outdoor/tidal) pool, and they let us swim when the water had been checked at 60F for three days: after that we swam every week, whatever the temperature dropped down to. At the local (outdoor/tidal) public pool, the temperature was almost always recorded on the information board as 52F - but we knew that often it was really 48F - the pool guys thought that no one would swim if they put that on their board! I think I once swam at 42F - but even the most dedicated swimmers could only stay in for a short time at that temperature.
No way could I do that today - I'm now 78 years old! - though I'm sure people do still swim at those temperatures in Scotland and other cooler places. And I still love swimming - now in indoor pools in London! Elizabeth