Posted: April 12, 2006

Athletics: Gatorade Sports Science Institute Issues Hydration Recommendations for Boston Marathon Runners

Guidelines to Help Participants Prevent Both Dehydration and Hyponatremia in This Year's Race

To help runners have a safe and successful performance at the 110th Boston Marathon, the Gatorade Sports Science Institute (GSSI) has developed hydration recommendations to aid runners in managing the risk for both dehydration (the loss of body fluid) and hyponatremia (low blood sodium levels due to excessive drinking and inadequate sodium intake). These recommendations have been distributed to all Boston Marathon participants in preparation for this year's race.

"The health and safety of all participants in the Boston Marathon has always been our priority," said Chris Troyanos, ATC, medical coordinator for the Boston Marathon. "Dehydration and hyponatremia are both serious concerns, and we believe that these hydration recommendations will provide important guidance to runners to help them reduce the risk of these conditions on race day. It's essential that runners keep hydration top of mind, and make sure to drink enough to prevent dehydration, but avoid overdrinking."

The recommendations developed by GSSI focus on the importance for runners to gauge their own fluid needs, rather than drinking according to thirst or following a specific rule of thumb for fluid intake. An effective hydration strategy combines adequate fluid and electrolyte intake -- not too much, not too little. According to the hydration recommendations, runners can gauge their individual needs by weighing before and after training runs to understand if they typically lose or gain weight. Based on this information, they can adapt their fluid intake accordingly to minimize their losses or gains.

For the vast majority of runners, dehydration, not hyponatremia, will be the key challenge. However, runners should be cautioned that hyponatremia during marathons is the result of aggressive over-drinking of any beverage -- actually drinking so much that substantial weight is gained before, during, or after the event -- and under those circumstances, runners should cease drinking immediately.

The GSSI hydration recommendations also highlight the importance of ingesting sodium during a marathon, especially for heavy sweaters and salty sweaters. Research shows that consuming sports drinks during a marathon helps runners replace some of the sodium lost in sweat and that will help assure proper hydration -- reducing the risk of both dehydration and hyponatremia. Also, newly published research in the British Journal of Sports Medicine (40:98-105, 2006) concludes that sodium-containing sports drinks will delay the development of hyponatremia compared to consuming just plain water (for those who do not over-drink any type of fluid).

"The two most important things runners can do to protect themselves from hydration-related problems is to drink according to their individual fluid needs and make sure to consume adequate sodium," said Dr. Bob Murray, director of the Gatorade Sports Science Institute.

Research conducted by GSSI with endurance athletes has shown that during long-distance training and competitions, such as preparing for or competing in a marathon, sweat and sodium losses can be substantial. To help offset these losses, athletes should increase their sodium intake throughout the day and during training and racing. The GSSI research led to the development of the specialized Gatorade Endurance Formula which was introduced last year. Gatorade Endurance Formula contains approximately twice the amount of sodium (200 mg/per 8 oz) of Gatorade Thirst Quencher to help meet the needs of athletes during prolonged exercise. For the first time ever, the Boston Marathon will be providing Gatorade Endurance Formula on course at this year's race. An estimated 30,336 gallons -- or over 647,000 servings -- of Gatorade Endurance Formula will be served at the race.

To learn more about Gatorade Endurance Formula and their hydration needs, runners can visit www.itsonthecourse.com.

The Gatorade Sports Science Institute is a research and educational facility dedicated to enhancing the performance and well-being of athletes. A team of sport scientists conducts research in sports nutrition, exercise science, fluid replacement and temperature regulation. Each year, hundreds of athletes are tested at the GSSI facility, which is equipped with state-of-the-art scientific equipment, to study the effects of nutrition on exercise and performance. More information is available online at GSSIWeb.com.

Source: Gatorade

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