Hot Weather Hydration — Proceed With Caution!

Book cover - Waterlogged, by Timothy Noakes
Tim Noakes’s book offers advice on our true hydration, electrolyte replacement, and carbohydrate requirements.

Halfway through the American River 50, I noticed wet squiggles on the trail.

Could this be the honored pee of Sean Crom?

Trail runners, particularly elites like Crom (he won AR50 that year), develop the skill of letting fly without stopping or slowing down, while artfully not besprinkling themselves. Hence the giggle-worthy squiggles on the trail.

I imagine some proprietous soul being offended by Crom’s peregrinating porta-potty target-practice.

In fact, there were lots of squiggles on the trail. Yet there’s solid evidence that it might be a good idea if we cooled our jets.

That is, if we drank (and peed) less.

During a recent visit to Stumptuous, a leading strength-training site for women, I discovered a very informative, entertaining 38-minute interview with legendary running physiologist Timothy Noakes, MD on the perils of overhydration.

Krista Scott-Dixon
Stumptuous owner Krista Scott-Dixon is a smart cookie, a PhD who formerly taught at York University. Her interview with Tim Noakes is wonderful.

The current dogma tells us we can never drink enough. But Noakes,  the author of Lore of Running, has amassed overwhelming evidence that drinking till our bladders burst is wrong.

A good way to spot a flawed scientific dogma is to pay attention to the folks who defy it with success.

  • After the Holyoke Marathon in 1963, legendary marathoner Ted Corbitt  compared notes with the other race leaders on the factors that enabled them to survive the terrible temperature, which soared above 103 degrees. (The race became known as the Holyoke Massacre.)

It seems the runners who weren’t troubled by the heat had two things in common: they ate a low-salt diet, and they didn’t gorge on fluids. (To be fair, nobody drank much in those days.)

  • The Bushmen of the Kalahari Desert perform amazing athletic feats in a part of the world where temperatures are high and there’s very little water.

The Bushmen count themselves lucky if they can sip tiny amounts of water from the sand with a straw. Yet they routinely cover 30 to 50 miles in a day while running antelope to exhaustion.

  • In the mid-1990s, I ran for a year in a small training group led by Carl Ellsworth, a regional age-group champion. Carl ran sub-3:00 at age 63. Three years straight, he won the 60-65 division of the NorCal AAU race series.

And, guess what, Carl never drank during marathons.

Having been schooled in the drink-up dogma, I worried aloud that Carl might be hurting himself. But he only smiled and said, in his quiet, courteous way, “Well, I’m only out there three hours.”

water bottle with X
Use with caution.

The old dogma says we should drink until our pee is clear.


The old dogma says we should drink at least 1.3 liters per hour.


The old dogma says we should replace all of the fluids we lose while running,  during the run.


The old dogma says we should force down the scientifically correct amount of fluids even if we aren’t thirsty.


Sheesh, where will it end? First the high priests of exercise backtrack on the 80-year doctrine that lactic acid “causes fatigue.”

Then they announce that minimalist shoes don’t really make us faster.

Now it’s water, which was once good for us but can actually make us die.

What’s next? Will the lab guys tell us to stay in bed and avoid life, which, after all, can be quite dangerous?

Or will we stop praying, gap-mouthed, to the lab priests with their PhDs and start listening to our own bodies?

In the interview, Noakes lays out the sad story of the sports-drink industry, which played a huge role in spreading “Thirst Quencher” propaganda, while ignoring and even suppressing contradictory evidence.

The folks at Hammer Nutrition have always argued for moderation in fueling and hydration. Yet the hydration guide on their website claims that losing 11% of body weight as fluids in a race will inevitably result in death.

In the real world, the picture is quite different. Noakes points out that Haile Gebrselassie lost 12% of his body weight while running a 2:03.59 world record at Berlin in 2008, yet he ran faster at the finish than at the start, and he felt fine.

The moral of the story? Listen to the interview. Read Noakes’s Waterlogged. And follow your thirst.


Here’s an amusing send-up of the running drinks industry. The video targets runners and weighlifters. It’s spot-on.

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