New York Times May 6, 2003 New Advice to Runners: Don't Drink the Water By GINA KOLATA
Every athlete, every fitness enthusiast has heard the advice to drink plenty of water. Drink as much
as you can. Don't wait until you are thirsty. By then it may be too late. You may be seriously
dehydrated, risking dizziness, collapse, even death. "Stay ahead of your thirst," athletes and
would-be athletes are told.
But now USA Track & Field, the national governing body for track and field, long-distance running
and race walking, says that advice is wrong. In what it calls a major revision of its guidelines,
the organization says endurance athletes, who may be consuming huge amounts of water over the course
of a long event, may risk seizures, respiratory failure and even death from drinking too much.
Instead of drinking as much as they can, the new guidelines say, runners should drink when they are
thirsty. People in long races like marathons may want to weigh themselves before and after long
practice runs to see how much they lose from sweating and drink that amount when they race, and no
more. The guidelines are at www.usatf.org.
Dr. David E. Martin, an exercise physiologist at Georgia State University in Atlanta, called the
change revolutionary and overdue. He is a co-author of a new advisory statement on fluid
replacement in marathons written for the International Marathon Medical Directors Association.
It was a supporting statement for the track and field advisory.
Ds. Martin said the old advice was leading to water gorging, with people stopping at every water
stop, downing water cups and so diluting their blood that their sodium levels plummeted, a
condition known as hyponatremia.
The problem occurs in any endurance event that gives people the time to drink and drink and drink.
It emerges among people who hike the Grand Canyon, in those who compete in Ironman Triathlons and,
most notably, in marathons.
Hyponatremia is not a problem for elite marathon runners, Dr. Martin said, because they go too fast
to drink too much. "Running at a five-minutes-per-mile pace," he said, "there's no way you can drink
enough to get hyponatremia."
Those runners, he added, have their own water stations, the elite water stops, where they have their
own sports drinks that they have chosen in advance.
Instead, Dr. Martin said, the problem is with slower runners, who may take as long as nine hours to
run a race. They may be running with groups of friends, raising money for a favorite charity. Or
they may be tourist runners, people who plan vacations around marathons.
"We're worried about this increasingly large group of people, taking courses in how to run a
marathon, going to shoe shops to learn how to run," Dr. Martin said. "What has been told to them is
the party line. Make sure you drink. You can't drink too much. Carry water with you or you will get
dehydrated. Don't worry about heat, just drink more. That's wrong. It's wrong, wrong, wrong."
What about the risks of dehydration, leading to heatstroke as the body temperature soars? Grossly
exaggerated, medical experts say. Most athletes who collapse at the finish line suffer from postural
hypotension, a drop in blood pressure when blood pools in the legs, and not from heatstroke.
Examining information on illnesses in marathons since 1985, Dr. Martin and Dr. Tim Noakes of the
University in Cape Town in South Africa, write in the advisory statement, "It has been difficult to
find any studies in which dehydration has been identified as the sole important causative factor in
even a single case of exercise-related heatstroke."
But they reported that they found 70 cases of severe hyponatremia.
Many start the race overhydrated, having fallen for what Dr. Heinz Valtin, a physiologist at
Dartmouth Medical College, deems a medical myth: that dehydration is always lurking and must be
fended off with more or less constant sipping of water.
In a paper published in November in The American Journal of Physiology, he said he could find no
scientific support for the common advice for healthy adults to drink at least eight glasses of water
a day and that the benefits that have been claimed - weight loss, relief of constipation, less
fatigue, increased alertness and so on - have no foundation in rigorous studies. "In my opinion, the
vast majority of healthy people do not need that much water," he said.
Dt. Martin agreed, saying: "People have been carrying bottles of water with them. Some people
actually get water intoxication syndrome. They feel lethargic from drinking too much. I worry
about the sanity of those people."
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Richard Ney