Water Wars: The Dehydration Debate

  • By T.J. Murphy
  • Published May 10, 2013
  • Updated Jun 17, 2015 at 5:06 PM UTC
Photo: Jon Davis

Does dehydration improve performance? This question and an onslaught of iconoclastic ideas about hydration have broken wide open in triathlon.

This article was originally published in the March/April 2013 issue of Inside Triathlon magazine.

Although he filed away his first two attempts at the Hawaii Ironman as epic disasters, Scott Molina was optimistic about his chance in 1983. The hard-edged, long-haul event seemed remarkably well suited for him. He had grown up in Pittsburg, Calif., where he excelled in cross-country, track and swimming at De La Salle High School. He had an affinity for hard work and high mileage even as a prep, recalling that he spent a lot of his time in class fighting the urge to sleep. In the early 1980s, through a blue-collar work ethic, Molina had begun snatching victories on a steady basis, setting the pace for a career that would yield more than 100 wins. His ascent had earned him a spot on Team JDavid, a professional triathlon team that included established stars like Mark Allen, Scott Tinley and John Howard, and provided bikes, a monthly stipend and trips to big races. Triathlon was beginning to come of age and Molina was rising with it. But it was in 1983 that his weak spot began to glare in a painful way.

“Going into Kona in ’83 I had had a great season, winning just about everything, so I had a good reason to be optimistic about doing well there,” he says.

It was during his two weeks of pre-race training in Kona that cracks in his relationship with the island began to surface. “I remember a few episodes during runs of just stumbling around on the highway not sure where I was. And a few times during long rides I had to pull over to sleep.” He was getting 10 hours of sleep a night and taking two-hour naps during the day, so the spells were mysterious. “I thought I had a virus,” he says.

The race was a disaster. “I had absolutely nothing in that race and ended up dropping out on the bike, completely depressed and vowing to never do that fucking race again.” A week later, Molina was fine, yet it would take him another five years to figure out the sodium-and-water puzzle that was his nemesis in Kona.


Molina’s education in subjects like hydration, electrolytes and hyponatremia came during the decade that witnessed an extension of the 1970s running boom, along with a triathlon boom, and the boom of the sports drink business—an industry that, according to a recent industry analysis by the SymphonyIRI Group, generates nearly $4 billion annually in sales. As described by  doctor, researcher, ultra-runner and prolific author Dr. Tim Noakes, capitalizing on the growth of the emerging endurance world required innovative marketing strategies because at the end of the day the product wasn’t some secret chemical or pharmaceutical creation. Rather, a sports drink is not much more than water, sugar and salt. In his 2012 book, Waterlogged: The Serious Problem of Overhydration in Endurance Sports, Noakes argues that the public has been hypnotized into believing that even minor levels of dehydration are dangerous to both performance and health—beliefs that aren’t supported by the body of research that exists. The information about hydration, Noakes claims, has been compromised by the cozy relationship between sports drink giants and scientists doing the studies. Noakes lays out a case against the institutionalized warning that our sense of thirst is an inadequate measure of how much we should drink and that, in fact, drinking too much is the real problem, not drinking too little. Drinking too much can screw up performance for one thing. And two, it can kill you.

Writes Noakes, “It is disturbing that incorrect advice to the public and the public’s own susceptibility to effective promotional efforts resulted in a novel medical condition that affected thousands of soldiers, hikers, runners, cyclists, and triathletes, causing some to die.”

Waterlogged is an important read for any coach or triathlete because it gives an uncommon critique of the endurance sports research mechanism, a system Noakes has been a part of since the 1960s. He reveals both a back story and an under-story within the subject of hydration and endurance, discussing how humans physically evolved to be effective hunters on the African savannah with the capacity to run long distances in hot weather with nothing more than an ostrich egg as a canteen. He explores the early studies on hydration by Dr. David Costill at Ball State and how in the early days of the marathon, the general rule of thumb was to drink little, if anything. He details the birth and expansion of a sports-drink-sports-science complex, through the different versions of the American College of Sports Medicine guidelines—which, at times, he claims, have been dangerous. In the 1970s, Noakes became an advocate for guzzling liquids during exercise, recommending 30 ounces of fluid per hour and in 1981 writing an essay that basically said to drink as much as you can possibly drink, a protocol counter to how runners of the time ran (they refrained as much as possible from drinking fluids during a race). It was a month after writing the essay, Noakes says, that things changed for him. He received a letter from a runner who almost died during the 56-mile ultra-distance race known as the Comrades Marathon, and an analysis of the problem led him to realize the risks of drinking too much in relationship to hyponatremia.

In the 1990s, Noakes spent time at the Hawaii Ironman, studying the event and working in the medical tent. In 1996, the American College of Sports Medicine had published recommendations on hydration that keyed on disregarding your sense of thirst and to discipline yourself to drink as much as you can. Noakes believes that a spike in hyponatremia problems for endurance athletes followed. After the Hawaii Ironman in 1998, he described the alarm he was experiencing in the med tent. “Lots of bellies sloshing full of liquid,” he said, a clear sign to him that competitors were drinking too much. Certainly the sloshing wasn’t particularly an enjoyable sensation while ticking off the miles of a marathon, and presumably not helpful at all to performance, but Noakes was more concerned about the severe consequences at stake when it comes to hyponatremia.

According to Noakes, a hyponatremia-stricken triathlete probably experiences the following: He or she is chugging 40 ounces of fluid per hour, and the brain interprets the situation as one where dehydration is involved and compensates by secreting an anti-diuretic hormone. Only half of the fluid intake is being sweated away, so hour upon hour the tissues of this Ironman triathlete are swelling up with water. When an excess of 60 to 80 ounces is backlogged, the brain swells within the unforgiving confines of the skull, and oxygen-carrying blood gets shut off to the brain. If you’re lucky you just pass out. If you’re not so lucky, you stop breathing.

Waterlogged is clearly aimed at revealing the insidious patterns of how sports drink companies support research scientists, and in this objective Noakes doesn’t spare himself. He explains that he was swayed by free Nike running shoes to advocate—as he did in his previous book Lore of Running—certain running shoe technologies that in fact had no valid scientific support in the first place. In Waterlogged, he reports the results of a self-examination in corporate influence. “Writing this book has made me more aware of the effects of accepting even the most innocuous gifts from [the] industry. How could a few dozen pairs of shoes over decades possibly influence my thinking? But it did. Because I was (and still am) a Nike guy.”

So there you go. If creating a race hydration plan to pursue a PR wasn’t complicated enough, one of the best sports scientists in the world is warning you to beware of sports science.

In talking with acclaimed coach and author of the Triathlete’s Training Bible, Joe Friel, the only research studies he pays attention to with respect to endurance performance are the ones that look at performance versus dehydration in a race, as opposed to studies performed in the lab on treadmills. One such study was published in 2010 in the British Journal of Sports Medicine. Noakes, as a matter of fact, was one of the eight researchers involved. The study set out to assess the relationship between the change in body weight that occurs in a marathon and performance. Six hundred forty-three finishers of the 2009 Mont Saint-Michel Marathon in France were weighed before and after the race. What the researchers found was counterintuitive to the mantra that says dehydration robs you of performance. They found an inverse relationship between performance and hydration: Those who lost the most weight during the race were the fastest. According to the researchers, the data matched a growing amount of evidence that “the most successful athletes in marathon and ultra-marathon running and triathlon events are frequently those who lose substantially more than 3–4 percent body weight during competition.” The results synced with a claim, reported in Runner’s World and in Noakes’ book, that Ethiopian running legend Haile Gebrselassie lost 10 percent of his meager body weight in his world-record marathon performance.

Reading studies about how the best runners were often the most dehydrated reminded me of the 1996 U.S. Olympic Trials marathon. Bob Kempainen, a medical school student at the time and former standout runner from Dartmouth, was leading the race as the top guys passed the 20-mile mark. With a network TV camera focused squarely on Kempainen’s sinewy frame from the side, viewers began to notice the runner pitch forward and back slightly, and then, in a series of orange explosions, puke out long bursts of sports drink. The lead commentator freaked out a bit, worrying aloud about Kempainen’s health, while color commentator (and Olympic marathon gold medalist) Frank Shorter essentially laughed it off. Indeed, after throwing up the contents of his stomach, Kempainen shifted into a faster gear, pulling away from the field and winningly handily. Later Kempainen would dryly remark, “I certainly felt better after I vomited.”

In the Nov./Dec. 2012 issue of Inside Triathlon, nutrition writer Matt Fitzgerald reported on the wave of research that may help explain what’s going on in a case like Kempainen. Following the classic guidelines of 30–40 ounces of fluid per hour, an amount delivering 60 grams of carbs if it’s a sports drink—as what apparently Kempainen tried to do in vain—may not help you go faster and may backfire. As Fitzgerald translated from the new study, “Such high rates of fueling can cause gastrointestinal discomfort and offer no performance benefit compared to just drinking by thirst.”

Drinking according to thirst—this is the main thrust of the recommendations Noakes now makes, and is the central advice Joe Friel gives to triathletes. Is it possible that triathletes at races like the Hawaii Ironman have been sabotaging their race efforts by trying to keep up with the torrid pace of the guidelines established by the ACSM in 1996 and adopted by dietitians and coaches, and ultimately reported by consumer publications like this one?

One triathlon coach surely agrees that this is the case. Team TBB’s Brett Sutton, the most accomplished triathlon coach in history, once told me about how in his early years of coaching swimmers in Australia through grueling workouts upward of two hours long, there wasn’t so much as a thought of water breaks. No one complained and no one apparently suffered. He had told me this during a Team TBB swim workout in the Philippines, minutes after he had spotted a water bottle on the pool deck where one of his athletes had set it up next to a pair of paddles, hoping to take sips between intervals. Sutton grabbed the bottle and chucked it into a nearby baby pool, telling the athlete, “When they put aid stations out there for you during the Ironman swim, I’ll give it back to you.”

RELATED: Staying Hydrated On Long Runs

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FILED UNDER: InsideTri / Nutrition / Performance Nutrition

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