Sep 29, 2015
My guests today are Dr.
Sam Cheuvront and Dr. Robert Kenefick
- Two of the world’s
leading scientists in hydration and fluid homeostasis
- Going in alphabetical
- My first guest is
Research Physiologist and Team Leader of the Thermal and Mountain
Medicine Division at the US. Army Research Institute of
Environmental Medicine (also known as USARIEM). His research
includes the study of environmental and nutritional factors
influencing human work performance. He is a leader in the fields of
human fluid needs, dehydration assessment, heat stress mitigation,
and exercise thermoregulation. He’s published over 100
-peer-reviewed papers and book chapters. Our first guest is Sam
Cheuvront, PhD, RD
- My second guest is Principal Investigator in the Thermal and
Mountain Medicine Division at USARIEM. He has published over 90
peer-reviewed manuscripts, book chapters AND reviews on fluid
homeostasis and the physiological responses to environmental
stress. He served as the president of the New England Chapter of
the American College of Sports Medicine and received their Honor
Award in 2012. He is also part of the Ultra Clan as an ultra
marathon runner himself. Our second guest is Robert Kenefick,
My guests work for the U.S. Army. So, we must provide the
disclaimer that "The views and/or opinions of Dr.'s Kenefick and
Cheuvront are theirs personally and do not reflect the views or
opinions of the U.S. Army or DoD."
Part 1: BASIC PHYSIOLOGY - FLUID & ELECTROLYTE BALANCE
This episode is the first in a two part series on fluids,
hydration, and electrolyte physiology pertaining to ultra marathon
running. We’re starting with the basics and progressing to specific
In this episode, you'll learn the answers
- What are the major body fluid and compartments and definitions
the major relevant terms (de/eu/hyperhydration,
- What are the mechanisms/routes and quantities of water
- How much water does a person need each day?
- Drinking to thirst - is it sufficient, like you hear commonly?
- How much salt is lost in sweat - only sodium? To what extent
does this change throughout the time-course of an ultra
- What’s in sweat and what are ranges of rates and composition in
- During exercise, the majority of water gained is in the form of
what we drink. But we have heard about getting water also from the
breakdown of stored glycogen. Is this accurate?
- How can we expand our plasma volume?
- When do we need (and not need) an electrolyte-containing drink
either during or after exercise?
- What is needed in an electrolyte drink beyond sodium?
- Hyponatremia; should it be a concern for most ultra marathon
- When does a runner need to consciously add sodium, beyond just
AND MUCH MORE...