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Get Naked to Stay Hydrated


Doug Casa is one of the nation’s leading experts when it comes to sports hydration, having written hundreds of papers and delivered countless talks on the subject. Casa can talk at length about the science and research behind hydration, but says the best advice he can give is quite simple:

Get naked.

Casa, a professor of kinesiology at the University of Connecticut who also directs the school’s Korey Stringer Institute, is not advocating streaking. Instead, he advises athletes to weigh themselves nude before and after training sessions to get an idea of how much water they should be drinking.

The difference in weight, minus the amount of liquid consumed during training, goes a long way toward determining an athlete’s fluid needs. USA Track & Field recommends athletes consume 1 liter of fluid for every liter lost during a race, but some athletes require more, especially during longer training sessions.

“The best thing you can do is come up with an individual hydration plan,” says Casa, a victim of heatstroke himself while running as a teenager.

The Korey Stringer Institute, which is partnered with the NFL and Gatorade, was founded in 2010 and named after the Minnesota Vikings offensive tackle who died in 2001 from complications of heatstroke. KSI’s mission is to educate athletes on how to avoid heat-related illnesses, especially heatstroke. In recent months, KSI staff has researched hydration with elite Ironman triathletes from the Timex Multisport team. This spring, KSI will work with the New York Giants. Football players and triathletes often train under intense heat. Regardless of your sport or climate, a proper hydration plan is important for optimal performance and avoiding heat-related illness. Casa recommends the following:

1. Practice How You Play

Athletes know the importance of not introducing anything new on game day, whether it’s equipment or nutrition. But they often give little thought to their hydration plans, whether the plan includes just water or a combination of water and sports drinks. “What you drink during training should be the same as what you drink during a game or race,” Casa says. “Not just the amount or rate of fluid consumed, but also the type of fluid, flavor, and the amount of sodium.”

2. Check for Color

Urine should be clear or at least no darker than pale lemonade. If it looks like apple juice, it’s time to drink more. This applies to pre-workout and for everyday life.

3. Drink Often

Casa says most athletes need to drink more during a training session and competition—and definitely more frequently. “It’s often a case of not drinking often enough,” he says. “So many times football players get one longer break to drink during practice. That’s not a good strategy. You’d rather have more frequent shorter breaks. The same is true with endurance athletes.”

How is hydration tied to performance? For every 1 percent of body mass lost, your heart beat increases 5 beats per minute and your core temperature increases a half degree Fahrenheit. “The more body mass lost, the more your performance is downgraded and we start to see potential health risks,” Casa says.

As a general rule, start drinking water as soon as you wake up and aim to drink about half an ounce to an ounce of water per pound of bodyweight throughout the day. So if you weigh 180 pounds, aim for 90 to 180 ounces of water daily. For more tips to stay hydrated, visit CorePerformance.com/Hydration.

About The Author

Pete Williams – Pete Williams is a contributing writer for CorePerformance.com and the co-author of the Core Performance book series.

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Tags: Hydration, Sports Performance, Energy, Health