J14 — April 2009 — Runner Science

Intro: Running a marathon can be a grueling effort, even for well-trained athletes. Runners can suffer electrolyte imbalances and even kidney problems. An important factor in all this is hydration. But how much and what should runners drink? Those are questions doctors at Mayo Clinic want to answer. They're studying the effects running has on the human body in hopes of being able to tell runners and other endurance athletes how best to prepare for an event.

RON PORTER IS ABOUT TO RUN HIS 10TH MARATHON.

"IT'S REALLY ABOUT THE CHALLENGE. TO GO OUT AND IMPROVE MYSELF AND IMPROVE MY TIMES."

BUT BEFORE THIS 26.2, HE AND HUNDREDS OF OTHER RUNNERS ARE GIVING THEIR VITAL SIGNS AND A FEW DROPS OF BLOOD TO RESEARCHERS AT MAYO CLINIC.

"WE WANT TO SEE WHAT KIND OF HYDRATION STRATEGY THEY'RE USING.

[SOUND OF STARTING GUN: BOOM!]

AND THEN LOOKING AT WHAT ADVERSE OUTCOMES THEY MIGHT ENCOUNTER AFTER RUNNING THE RACE."

DR. MICHAEL MOHSENI AND HIS TEAM ARE ANALYZING RUNNERS' BLOOD SAMPLES TO FIND OUT HOW HYDRATION, [NATS: "WATER"] WHAT AND HOW MUCH RUNNERS DRINK, AFFECTS SODIUM LEVELS AND KIDNEY FUNCTION. YOU SEE, SODIUM IS AN ELECTROLYTE. IT WORKS WITH OTHER SUBSTANCES TO STABILIZE CELL MEMBRANES AND KEEP YOUR MUSCLES FUNCTIONING PROPERLY. IF YOUR SODIUM LEVEL DROPS TOO LOW FROM TOO MUCH WATER OR EXCESSIVE SWEATING, YOU CAN DEVELOP WHAT'S CALLED HYPONATREMIA. SYMPTOMS INCLUDE NAUSEA, VOMITING, SEIZURES AND IN SEVERE CASES, DEATH. RUNNERS MAY ALSO DEVELOP A DECREASE IN KIDNEY FUNCTION FROM DEHYDRATION. MOHSENI'S RESEARCH WILL REVEAL WHICH RUNNERS MAY BE MORE PRONE TO DEVELOPING THESE PROBLEMS. AND WITH THIS INFORMATION HE HOPES TO MAKE RECOMMENDATIONS AS TO HOW RUNNERS SHOULD PREPARE FOR A RACE IN TERMS OF WHAT AND HOW MUCH THEY DRINK.

"IT'S SIMILAR TO RESEARCH DONE ON SPORTS DRINKS THAT SHOWED RUNNERS WHO DRINK LIQUID FORTIFIED WITH ELECTROLYTES AND ENERGY DO BETTER THAN RUNNERS WHO DRINK WATER ALONE."

RESEARCH THAT WILL HOPEFULLY HELP RUNNERS STAY HEALTHY AND IMPROVE THEIR PERFORMANCE.

FOR MEDICAL EDGE, I'M VIVIEN WILLIAMS.

Anchor tag: Dr. Mohseni says preliminarily his data shows that about 8-percent of marathon runners experience issues with hyponatremia and up to 19-percent have decreased kidney function. The good news here is that most runners recover on their own quickly after a race. But he hopes his research will show how hydration can prevent these issues.

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