You have asked a question that could cause you dire consequences.

I think that you should spend some time educating yourself and have an informed discussion with your physician.

If you don't like my answer, then you get a free bump and I hope that you get more responses.

Rob,

Everyone has a unique electrolyte concentration in their sweat. Which means you could be losing significantly more electrolytes than you are replacing - even when temperatures are mild.

You can undergo a sweat test to determine the amount of sodium/electrolytes you are using and then have a plan created to replace them more effectively/efficiently.

Our company specializes in testing endurance athletes in various areas of nutrition and performance. Check out our website and feel free to contact us with any questions.

Team Four3
http://www.teamfour3.com

1. I doubt that your sweat rate / composition has changed, so in that regard, your body has not made "physical" changes to make you more susceptible. However, I could certainly see a "central governor" (if you believe in such a system) being less sensitive and allowing yourself to become dehydrated (ie less warning signs). In this case you may need more conscious effort to follow a pre-determined schedule instead of relying on "thirst" or "feel".

2. Determine sweat rate and composition in a variety of situations such that you can have a strong estimate of what you output is on race-day. From there, do math. Feel free to be in touch with me at that point as I've worked out calculations for maintaining osmolality in the blood within normal ranges based on sweat rate / composition and various re-hydrating strategies.

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I talk a lot - Give it a listen: http://www.fasttalklabs.com/category/fast-talk
I also give Training Advice via http://www.ForeverEndurance.com

The above poster has eschewed traditional employment and is currently undertaking the ill-conceived task of launching his own hardgoods company. Statements are not made on behalf of nor reflective of anything in any manner... unless they're good, then they count.
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