Damn you, mammalian diving reflex!

Over the years, I’ve done some triathlons to spare my body from the effects of too much pavement pounding. One of my favorites is the Colby triathlon, which has several advantages: the distances are very manageable, the event is nearby, and the entry fee supports the Nordic ski team. I did this event the very first time it was held back in 2005 and decided to give it another go a few months after knee surgery in 2011 (which didn’t seem crazy at the time, but as I write this, it kind of does). Not surprisingly, my time was slower in 2011 than in 2005, so my goal was to improve in 2012.

The swim has always been the most challenging part of any triathlon for me, so this is where I decided to focus my efforts. I got some tips on my technique from one of my research students on the swim team and did more open-water swims in preparation. I even found a low-key neighborhood triathlon, put on by a couple of Colby alums and their friends, to boost my confidence. (Jorma, a former Colby distance runner, completed this race with a dislocated shoulder a few years back by doing mostly sidestroke, and I figured I could probably at least beat him!) The course parallels the shore, meaning that you can simply stand up if you get tired or freaked out. I was pleased when I successfully freestyled the whole thing instead of having to resort to breaststroke partway through.

Fast forward to race day on Messalonskee Lake, where it was cold and rainy– way too cold to jump in the lake any earlier than absolutely necessary! I waited until the last possible second and then put my face in the water and started to swim. Almost immediately, my lungs contracted, and I was completely breathless, leading to increasing panic. Things got worse from there, and I never got my breathing right. Backstroke seemed like a wise course of action, despite it being little faster than Jorma’s sidestroke! The swim leg was a total disaster, and I felt lucky to have survived.

I have been disappointed with myself ever since for freaking out, but I realized during Cathy’s lecture last week that my body’s reaction to the cold water was not something that I could control. My heart rate slowed to decrease my body’s use of oxygen at a time when I needed just the opposite to occur. After the race, I chatted with some experienced triathletes and heard that they always force themselves to get in the water early and do a significant warm-up swim to acclimate their bodies to the cold water (plus, they pee in their wetsuits). But maybe it would be more effective to learn the Wim Hof method of tapping into my own inner fire for next time!

Feels like the Arctic Ocean!

Feels like the Arctic Ocean!

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2 Responses to Damn you, mammalian diving reflex!

  1. Fearless Leader ugogal says:

    I asked my favorite Colby swimmer about this, and this is what he said:

    I did not watch the Olympics close enough to see everyone dunking before their races. It is not a publicized practice to dunk before a race, though everyone warms up before a race. I get my hands and eyes wet before a race so I can feel the water and so my goggles stay on, Mason used to slash water on himself before a race, but other like to stay dry for a bit of time before a race. It all comes down to personal preference, but I can see where the acclimating idea would come from. On a physics level, water has a different coefficient of heat than just air, so wetting your body before a race will cool it down faster than not wetting it. When you then dive in, the shock may be less.

    That said, there are a bunch of other reasons swimmers may dunk before a race, including but not limited to: making sure the championship suit is snug in all the right places, testing caps and goggles for water leakage, and our favorite…peeing! Most of the time, the temperature acclimation is likely the reason though.

  2. dampbench says:

    You mentioned that triathletes tend to swim around in the water before racing in order to get themselves acclimated to the drastic temperature changes. When watching the Olympics this past summer I noticed that every one of the swimmers takes a dip in the pool before plunging into the water at race time. Do you think they’re employing a similar strategy? I understand that Olympic swimming pools aren’t nearly as cold as Maine lakes in late September, but perhaps even the slightest temperature shocks could have negative effects on performance. Am I even on the right track, or do they all jump in before the race for some other reason?

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