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Evaluating the Swim

November 20, 2011 By Charlotte Brynn

 I am on the mend, 10 days after the Memphre swim, I have a few light pool swims under my belt and another open water swim, I am feeling stronger every day, I still seem to tire very easily,and  my speed has slowed considerably,  but some good nights sleep is combating that nicely, there is one area still being examined by the docs, my liver enzymes are off the charts high, not normal I am told, ” I would like to take one final blood test, to see if they have lowered  before we refer you to a specialist”, says the doctor. 

In the meantime I have been doing some research of my own on the effects of marathon swimming on the body. I’ve come across some useful reading on electrolytes and also research completed by a physician curious on the effects on the body of a swim of 10 hours or more, he completed a swim himself and then drew blood pre and post swim, he  later completed the tests on a fellow physician and swimmer, the results were interesting indeed……

Here is an exert from his paper:

Swimming in the ICU

By Peter Attia

To study the physiologic impact of marathon swimming I decided to use myself as a guinea pig on during my Catalina swim in 2005.  My friend, Marc Lewis, who is also a doctor, drew my blood for a complete panel of labs 3 hours before I started my swim, and immediately after I finished.   Some of the lab results were ‘expected’, such as my sodium level going from a low-normal (142 mEq/L) to a high-normal (148 mEq/L), as a result of ingesting quite a bit of salt-water.  Some blood tests that measure dehydration – coupled with an immediate pre- and post-swim body weight – suggested I was neither dehydrated or super-hydrated.  However, the lab results that surprised me the most were the counts of my blood cells.  My CBC (complete blood count) was completely normal before the swim.  Immediately after, however, it showed changes compatible with a condition called SIRS, systemic inflammatory response syndrome.  Without getting into the details of SIRS, my white blood cell count and platelet count had risen from normal by 5- and 3-fold, respectively.  These blood results are typically seen in patients with profound infections or traumatic injuries, as a result of an inflammatory cascade in the body leading to margination of blood cells (e.g., certain types of white blood cells, platelets) and leaking capillaries.   Several months later, we repeated the experiment when Marc swam the Catalina Channel.  The results were the similar.  While a sample size of two is hardly worth drawing conclusions from, I am convinced that marathon swimming is stressful enough to induce an ‘inflammatory cascade’ in the body.  When the body is under extreme physical stress (e.g., infection, tissue damage), immune cells in the bloodstream are activated and release chemicals (cytokines), which dilate capillaries (leading to capillary leak), and inciting an inflammatory response throughout the body.

– swimming for 10+ hours is as stressful to the body as having the worst infection, or being hit by a car.  It is actually like being in the ICU.

 Well, I found this very helpful, my blood work was consistent to someone having been hit by a car, add in my water toxicity and we have ME  post swim.  I continue my research, reading articles on Hyponatremia and electrolytes, helpful reading on recommended electrolyte intake during exercise  confirming that my feed mixes were within recommended intakes and mixed correctly, excellent, but how did my body get so out of balance?

 Well I’ll never now for sure but after research, reading and meeting with my crew to talk things through here are our findings:

 Missing feeds early in the swim was a contributing factor

During hours 10-12 my feeds were accidentally diluted, less electrolytes going in

I swallowed some generous mouthfuls of lake water in the early part of the swim

I vomited some feeds up

What did me and my crew learn?

Some lessons on feeding at night and the importance of seeing how much water is added to the Maxim feed cups

Salty foods = good in fresh water swims

Leave some water in the lake

Make sure I finish all my feeds every time

 We also came up with a long list of things that went right, here are just a few…

Our communication was excellent

We were well prepared with our supplies and roles, we each new what we had to do, when things didn’t go to plan we readjusted and carried on, none of us panicked or ” threw our toys out of the cot”

My crew motivated me by lying about how far I had to go, and staying upbeat

We never gave up, I kept going and so did they

We completed the swim WAHOO

 

2 Weeks after the swim, not up to full speed yet, but I'm Bright eyed and bushy tailed

 So with the above  findings in hand, it is almost 2 weeks since the swim, we have one more blood test to retake, ” Doctor, I have a race in 2 days, we don’t have the final test results, are you comfortable with me swimming”, I ask the doctor over the phone, ” well how do you feel”, she asks, ” well, I am feeling much better than I was, I tire easily, I am not back up to full speed, but doing alot better and in good spirits”

 She replied with, ” swim, but just do what you can tolerate”, I thank her, as I hang up the phone I have a smile on my face like a Cheshire cat, ” PERFECT, I’ll swim and just do what I can tolerate”, I get the giggles, I know very well what that means to me, I am going to race full steam ahead WHAT FUN!

How much will I tolerate? I’ll keep you posted

Closing thought: “Better to be pruned to grow than to be cut up to burn”

                                   – John Trapp

Charlotte Brynn, Marathon Swimmer, Channel Swimmer, Ice Swimmer, Exercise Specialist

55 Marathon Swims, 2x International Ice Swimming Association Mile (1st New Zealander)

World Open Water Swimming Association’s (WOWSA) 50 Most Adventurous Open Water Women list – 2014, 2015, 2017, 2019

World Open Water Swimming Association’s (WOWSA) list of top women open water coaches and mentors in the world 2018

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