The Dehyrdation Myth & Running.

Nearly half of runners drink too much water. Are you one of them?

There’s no question that water consumption is critically important – and obviously necessary for survival. And, in fact, many of us don’t consume the recommended amount of H2O. But a recent study by Loyola University Health Systems found that nearly half of recreational runners might be drinking too much water during races.

Consider, for a minute, our early ancestors. When chasing or hunting down a meal, our ancestors didn’t encounter tables with small cups of water marking each mile – as a modern marathoner might. There wasn’t time to stop and get a drink; the hunt was on, and so the body evolved to run distances without hydration.

According to the Loyola study, which was published in the June, 2011, issue of the British Journal of Sports Medicine, “Many athletes hold unscientific views regarding the benefits of different hydration practices.”

Drinking too much fluid while running can lead to a potentially fatal condition called hyponatremia. When runners consume too much fluid, the sodium content of the body’s blood can drop to dangerously low levels. In fact, the study’s co-author, Lara Dugas, PhD, references 20 recent documented or suspected deaths from hyponatremia. It’s not theoretical; it happens.

To avoid hyponatremia, experts recommend that runners only drink when your body craves it. While marketers have warned us about the dangers of dehydration, runners need to find the appropriate balance. Dugas concludes:

We have been trained to believe that dehydration is a complication of endurance exercise. But in fact, the normal physiological response to exercise is to lose a small amount of fluid. Runners should expect to lose several pounds during runs, and not be alarmed.

Bottom line: Listen to your body and only drink when it is signaling thirst.

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  1. I think I should inform you that you’ve spelled “dehydration” wrong in the headline. Sorry, but spelling errors bother me.

  2. Maybe Davey has hyr (higher) dation (the act of giving something) on his mind.

  3. Just add some salt in the water and you won’t suffer hyponatremia 😉

  4. christopher says:

    the foto could be Davey-but thats not the point at alway too much water slows you up.and everyone knows too much water will bloat you big time.drink water-absolutely-but in absolute safe increments-im by no means an expert-after all DW-is the teacher-we are mere students-you defer his experience to him-as i do-you -you will get somewhere in life-DW-is a PT-you follow his direction-as i have-now and the future-you will be stoked-ive proven to myself and others-what can be done-i work out every day-threadmill-is my ticket-and everything-i mean everything falls in place-and it indeed does-im getting DWs-opinion-he literally makes me the total man-ive taken his advice-i just wouldnt be the man now without him.results are paying off-you wouldnt beleive what i looked one year ago-to what i looke like now.i am one success to what i looked like one year ago.ive 38 lbs/17kg to go-you blogbuddies plus DW-I AM GOING ON-thanks to you.

  5. Davey I can tell you from my exp. That drinking to much water is Bad when running. 6wks ago I had hyponatremia fainted and broke my jaw in three places,Kidneys failed, and blood pressure dropped down to 75. was in icu for 2days and Hosp.for 3 days while they pumped liquid into my body. They told me that this was do to the very fact that I was drinking to much water which was flushing out whatever electrolyte I had left in my body and a High blood pressure med I was taking making me even more dehydrated. Every thing is almost back to normal. S othe lesson I took from this is less water and more Drinks with electrolyte.

  6. I only do shorter running, somewhere between 5-10k every run usually 3 to 4 times a week.I really do not really feel the need to drink while running. I usually just have a glass of water before my run. If I drink more my stomach feels bad while on my first few miles. Only if it is really warm outside have I ever felt the need to stop and take a sip of water from a fountain on my route. Other than that it makes me feel sick even after my run I cannot drink for at least 20 minutes without feeling sick