Electrolyte Balance-Science Study

Study on Fluids and Electrolyte Balance: “Hyponatremia in Ultramarathoners”

By Joseph N. Chorley, M.D., Principal Investigator, Lisa S. Bliss, M.D., Medical Director and 2004 Badwater Finisher, and Jeffrey S. Lynn, PhD.

Many 2005 entrants were invited to participate in a research study that will help to define the fluid and electrolyte balance of extraordinary athletes in extreme environments like the Badwater Ultramarathon. The researchers were especially interested in studying hyponatremia (low blood sodium). Two research groups were utilized for this study:

  • Group 1: Questionnaire and blood and urine measurements BEFORE and AFTER the race only
  • Group 2: Same as group 1, but also have a questionnaire and blood draw at Stove Pipe Wells (42 mi) and Panamint Springs (75 mi)

The crews for participants in both groups were asked to record information about their runners’ food and fluid intake during the race.

Initial results were presented by Dr. Joe Chorley at the Endurance Special Interest Group at the ACSM Conference in June 2006.

“Myocardial Stress During and After Ultra-Endurance Running in Extreme Heat”

Leithäuser Renate M1, Doppelmayr Hildegard2, Doppelmayr Michael3, Finkernagel Holger4, von Duvillard Serge P5, Roth Heinz J6, Beneke Ralph1.

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A research study focusing on heart rate responses during ultra-endurance events took place during the 2005 race.

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