Water Wars: The Dehydration Debate

Does dehydration improve performance? An onslaught of iconoclastic ideas about hydration have broken wide open in triathlon.

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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.”

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But here’s the deal: Racing triathlon is different than running a marathon. Multisport hydration is a problem to be studied regardless of the “drinking by thirst” approach. Drinking by thirst may be relatively simple for the Olympic-distance crowd to implement—although two-time triathlon Olympian Sheila Taormina used very strict hydration protocols while on the ITU circuit because she felt the international travel demands made hydration complicated. She’d drink 96 ounces of water per day, and before a race would drink coffee, a 20-ounce bottle of water and another bottle of Amino Vital, a solution of water and electrolytes. Taormina told me that the high-intensity nature of elite Olympic-distance racing—often in hot weather—spiked rates of dehydration. “Your respiration rate is just so high,” she says. “I really had to learn how to deal with it.”

But the problem of race-day nutrition for the Ironman is a whole other lock to be picked. It’s not two hours on the course, or four hours, but at least eight and as much as 17. If it’s Kona we’re talking about, or races like Louisville for that matter, the weather can be hellish. Combine the conditions with driven triathletes out to win the race, or break 10 hours, or PR, and you have a blend of variables that make for a sort of physiological high-wire act. More than a few end up spewing into the lava fields, or bonking out of the race, or wobbling into the medical tent looking like they’d just returned from an alien spaceship. And beforehand there’s all sorts of advice being pumped your way in terms of how much to consume, how many carbs, protein or no protein, sodium, potassium, solids versus liquids, and the immoveable fact that each of us is at least a little bit different and may have different needs.


“Our whole goal is to make race nutrition simple,” says Brian Shea, president of Performance Best Nutrition, a small consulting company that mostly works with age-group triathletes but also tends to the needs of Ironman elites like Jordan Rapp, Julie Dibens and Rachel Joyce. Shea says he’s been racing triathlon “since before I had a driver’s license.” He originally studied kinesiology and, in marrying his exercise physiology knowledge with his triathlon know-how, friends began asking for his tips on race nutrition. Ultimately it became his career. “My job description, as it’s worked out, is this: ‘I tell people what to eat and drink during an Ironman,’” he says. His job took off after he helped American running great Deena Kastor prepare for the 2004 Olympics, where she took the bronze medal in a very hot marathon in Athens.

Although he studied kinesiology, Shea’s approach does not hang on every word emerging from the sports science world. Rather, he says, it’s about determining what works best for a client regardless of the literature. “Hey, if they’re using Pop-Tarts and it’s working, then we’re going to use Pop-Tarts.”

Shea starts off with a client by figuring out his or her sweat rate. This is usually accomplished with a list of questions where the athlete describes how much he or she sweats when training as opposed to any sort of high-tech testing.

Says Shea, “It comes down to questions like this: When you’re running on a treadmill, are you the guy who sprays everyone in the gym when you run?”

Once he has a ballpark idea of the client’s sweat rate and other notes from his or her training and racing past, he begins to sketch out a nutrition game plan to be tested in training and ultimately in racing. “We usually get things dialed after four to six trials,” he says. As they zero in on an ideal plan, Shea again says that whatever advice might be rendered from sports scientists, the ACSM, Tim Noakes, or others comes down to what makes an individual athlete feel good and perform well.

Shea doesn’t believe sports science is conclusive on subjects like hydration and hyponatremia for a lot of reasons. “A sports drink study might only have 100 subjects. Consider that a typical drug study involves 500,000 subjects.”

He considers his own racing. “I know what Noakes says about hydration and hyponatremia, but I also know how I feel using his plan and it doesn’t work for me. I don’t have a lot of rules. One thing I do get is some trickle-down from what works best for the top pros. Consider that at an eight-hour Ironman pace, they’re pushing the limits of intensity. I can definitely learn from that and use it to help out an age grouper.

When clients first come for his services, they often hit him with that glazed look that suggests they are at their wit’s end when it comes to figuring out what they’re supposed to drink and eat during a long race. “At the end of the day, all I’m looking for is something that works and something that is doable,” Shea says. “That gives the athletes the psychological confidence they need between the ears. And having their nutrition locked down gives them one less thing to worry about during race week.”


It wasn’t until 1988 that Scott Molina followed a protocol somewhat similar to the one Shea markets in his business. In trying to understand why he could race so well at just about everything except long distances in hot weather, he decided to check his sweat rate. “I found I was losing 3 liters of water per hour,” he says. He thought back to his days as a high school runner, logging high-mileage weeks in the sunburned foothills of Northern California on hot summer days, and remembered a certain frequent ordeal. “On hot days running in the hills, I had to stop at the cow troughs and part away the algae and scum from the surface to get a drink of water,” he recalls. “I got the nickname ‘Mucky Sludge.’”

So in the run-up to the 1988 Hawaii Ironman, Molina, aka Mucky Sludge, confronted with a rate of sweat loss that was even higher than he feared, attacked the problem directly both in training and in race strategy.

Molina’s solution became two-fold. First, he blasted himself with nearly two weeks of heat training in and around the desert town of Palm Springs, Calif.

“I averaged 100 miles a day on the bike for 11 days, with the longest ride being 183 miles and another one of 160 miles on a trip around the Salton Sea. Lots of climbing as well up into the mountains. Plenty of hard running in the heat, with some killer mile reps on the grass track that was there.”

The swimming offered no relief. “The pools there are 84–88 degrees in summer and we usually swam between 1 and 3 p.m.”

The second part of Molina’s solution was adjusting his pace with what he knew he could drink. Drinking too much in races would steer him toward hyponatremic states. “I just knew I had to slow down to absorb more. I had done the 20-mile run in the Nice International Triathlon, held in France, in under two hours just a couple weeks before, so I had a pretty good idea that I could run around 2:45–2:50 if it wasn’t too hot. I also knew from my track sessions and harder runs there that I couldn’t absorb very much water when running hard—it just sloshed around a lot in my gut like a washing machine!”

In the 1988 Hawaii Ironman, putting to use the radical exposure to Palm Springs temperatures and an understanding that he needed to calibrate pace with his hydration and sodium needs, Molina put an end to his nightmares in Kona with a 51-minute swim, a 4:36 bike leg and a 3:02 run, winning the 12th edition of the Ironman World Championship.

Everyone keeps searching for some perfect answer for matching hydration and performance, but perhaps Mucky Sludge blazed the path for us long ago. We each have to figure this out for ourselves.

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Nutrition Snapshot

Jordan Rapp’s Ironman Texas nutrition plan

One of sports nutritionist Brian Shea’s elite clients is American professional triathlete Jordan Rapp. Rapp is a brainiac who applies his considerable education—he studied mechanical engineering at Princeton—to the complexities of multisport. This includes nutrition, as Shea discovered. According to Shea, Rapp is not a typical consumer of Personal Best Nutrition’s services—in other words, he asks a lot of questions. “Most just want us to tell them what to do. Jordan wants to know exactly why he’s doing everything.” The following is Shea’s report of the nutrition plan Rapp used to win the 2012 Ironman Texas in 8:10:44.

Breakfast: 2 EnviroKidz Bars, 2 cups So Good Coconut Milk, 2 scoops Ultragen Cappuccino, 1 banana, 2 Laughing Giraffe Vanilla Almond Snackaroons, Half of a Green & Blacks 70% Chocolate Bar, 2 SaltStick capsules, 3 First Endurance MultiV and 4 OptygenHP capsules

Pre-race: 1 bottle of First Endurance with two scoops of EFS energy drink mix plus one scoop of First Endurance PreRace, 1 SaltStick capsule

Bike nutrition: Starting bottle: 3 scoops EFS plus 3 SaltStick capsules, 2 EFS Liquid Shot flasks (Kona Mocha flavor) with 20 ounces of water added to Shiv bladder, Second 26-ounce bottle containing 3 scoops EFS and 3 SaltStick capsules picked up at Special Needs, Approximately 3 bottles of on-course PowerBar Perform, 24 ounces water, 8 SaltStick capsules, 2 First Endurance PreRace capsules

Run nutrition: 1–2 small cups of Powerbar Perform and 1 small cup of Coke taken at every aid station, Zero water consumed on the run

A Hot Day With No Ice

Linsey Corbin’s home-cooked formula for Ironman racing success

In 2012, American Linsey Corbin earned Ironman victories in Austria and Arizona, the former coming in an event with grueling 100-degree temperatures. Corbin says winning in Austria coupled the extreme heat with an aid-station quirk. “In Europe they don’t have ice at the aid stations,” she says.

Corbin says she almost stumbled onto the race nutrition plan charted below back in 2006, a plan she counts on to this day. Confidence in her food and drinking schedule allowed her to channel all of her psychological energy into what was an especially challenging race. “It was a pretty hard day,” she recalls. “It got really hot on the bike. And I knew in the first two miles of the marathon it was going to get bad.” Corbin says that although she was running at a seven-minute-per-mile pace, “each mile felt like it took twice as long.” The pressure increased at a point in the race where a nutrition plan is most tested in an Ironman—with 10K to go, and with Hungary’s Erica Csomor bearing down. “I’m not used to being chased,” Corbin says. “With 10K to go she had turned my two-minute lead into 30 seconds.” Corbin’s mettle and the tuning of her nutrition plan held together as the American—listening to a shout from her husband, Chris Corbin, who said, “I’m done talking to you. Just run!”—relaxed and held on to break the tape for the victory.

Corbin’s Ironman Nutrition Game Plan

Breakfast: Approximately 1,000 calories for breakfast about 2.5 hours before the event (usually a muffin with peanut butter and honey, a small cup of granola or oatmeal, Clif Shot electrolyte drink)

Pre-race: 1 double espresso Clif Shot energy gel

Bike nutrition (Corbin says this varies a little depending on weather conditions): 1 Clif Shot gel every 30 minutes (10 total)—variety of flavors, about 3–4 caffeinated, Approximately 1 bottle of each per hour: water and on-course sports drink, 3 Hammer Endurolytes per hour

Run nutrition: 1 Clif Shot gel every 25 minutes (approximately 7)—mostly caffeinated, Water/ice/on-course sports drink/Coke – approximately 6 ounces every aid station, 3 Hammer Endurolytes per hour

Post-race “libations”: Chocolate milkshake, Big Sky Brewing Moose Drool

Corbin says the biggest “secrets” to her success for nutrition have been:

1. Consistent fueling throughout the day—taking in calories every 20–30 minutes—no matter how she is feeling

2. Proper pacing, which in turn allows for proper digestion

3. Doing nutritional “race simulations” in training to teach her body to digest calories at a tempo/race-pace effort

4. Being flexible with her plan and reacting to how her body is feeling/what it needs in a race environment

T.J. Murphy is a contributing writer to Inside Triathlon and the author of the book Inside The Box.

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