dehydration increases cortisol, decreases test response, alters carb metabolism

[Dr Pangloss]

Do yoursef a favor, take fluid and electrolytes in during your workout. Pretty simple stuff.


See below:


J Appl Physiol. 2008 Sep;105(3):816-24. Epub 2008 Jul 10.
Effect of hydration state on resistance exercise-induced endocrine markers of anabolism, catabolism, and metabolism.

Judelson DA (http://www.ncbi.nlm.nih.gov/pubmed?term="Judelson DA"[Author]&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsP anel.Pubmed_RVAbstract), Maresh CM (http://www.ncbi.nlm.nih.gov/pubmed?term="Maresh CM"[Author]&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsP anel.Pubmed_RVAbstract), Yamamoto LM (http://www.ncbi.nlm.nih.gov/pubmed?term="Yamamoto LM"[Author]&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsP anel.Pubmed_RVAbstract), Farrell MJ (http://www.ncbi.nlm.nih.gov/pubmed?term="Farrell MJ"[Author]&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsP anel.Pubmed_RVAbstract), Armstrong LE (http://www.ncbi.nlm.nih.gov/pubmed?term="Armstrong LE"[Author]&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsP anel.Pubmed_RVAbstract), Kraemer WJ (http://www.ncbi.nlm.nih.gov/pubmed?term="Kraemer WJ"[Author]&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsP anel.Pubmed_RVAbstract), Volek JS (http://www.ncbi.nlm.nih.gov/pubmed?term="Volek JS"[Author]&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsP anel.Pubmed_RVAbstract), Spiering BA (http://www.ncbi.nlm.nih.gov/pubmed?term="Spiering BA"[Author]&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsP anel.Pubmed_RVAbstract), Casa DJ (http://www.ncbi.nlm.nih.gov/pubmed?term="Casa DJ"[Author]&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsP anel.Pubmed_RVAbstract), Anderson JM (http://www.ncbi.nlm.nih.gov/pubmed?term="Anderson JM"[Author]&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsP anel.Pubmed_RVAbstract).
Dept. of Kinesiology, California State Univ., Fullerton, CA 92834, USA. [email protected]
Hypohydration (decreased total body water) exacerbates the catabolic hormonal response to endurance exercise with unclear effects on anabolic hormones. Limited research exists that evaluates the effect of hypohydration on endocrine responses to resistance exercise; this work merits attention as the acute postexercise hormonal environment potently modulates resistance training adaptations. The purpose of this study was to examine the effect of hydration state on the endocrine and metabolic responses to resistance exercise. Seven healthy resistance-trained men (age = 23 +/- 4 yr, body mass = 87.8 +/- 6.8 kg, body fat = 11.5 +/- 5.2%) completed three identical resistance exercise bouts in different hydration states: euhydrated (EU), hypohydrated by approximately 2.5% body mass (HY25), and hypohydrated by approximately 5.0% body mass (HY50). Investigators manipulated hydration status via controlled water deprivation and exercise-heat stress. Cortisol, epinephrine, norepinephrine, testosterone, growth hormone, insulin-like growth factor-I, insulin, glucose, lactate, glycerol, and free fatty acids were measured during euhydrated rest, immediately preceding resistance exercise, immediately postexercise, and during 60 min of recovery. Body mass decreased 0.2 +/- 0.4, 2.4 +/- 0.4, and 4.8 +/- 0.4% during EU, HY25, and HY50, respectively, supported by humoral and urinary changes that clearly indicated subjects achieved three distinct hydration states. Hypohydration significantly 1) increased circulating concentrations of cortisol and norepinephrine, 2) attenuated the testosterone response to exercise, and 3) altered carbohydrate and lipid metabolism. These results suggest that hypohydration can modify the hormonal and metabolic response to resistance exercise, influencing the postexercise circulatory milieu.

PMID: 18617629 [PubMed - indexed for MEDLINE]

[FlexMasterSexy]

hat does that mean in practice?

[Dr Pangloss]

hat does that mean in practice?


it means you should stay well-hydrated while you're working out. If you're losing several pounds of water, you will blunt your recovery and muscle gains, as cort levels stay high and test levels stay low.

[Ryan Wacht]

it means you should stay well-hydrated while you're working out. If you're losing several pounds of water, you will blunt your recovery and muscle gains, as cort levels stay high and test levels stay low.

This is so true, I've noticed that my progress completely comes to a halt when I don't drink enough fluids, even if on cycle.

[nitrous]

very cool thanks for posting that

[radrmd216]

Physical stress is a stimulus for the release of cortisol which is a trigger for gluconeogenesis. I guess since gluconeogenesis causes cells to use other forms of energy besides glucose, the result is impaired carbohydrate metabolism.

Dr. P, I remember hearing Scott Connelly say that gluconeogenesis occurs at 80% rate. What other mechanisms cause gluconeogenesis and at what rate does it occur during rest and physical activity.

I'm trying to find out more about gluconeogenesis, since Dr. Connelly is an advocate of a low carb diet and says the body can effectively use other molecules besides glucose for energy metabolism.

[juggernaut]

Interesting stuff. I do question and I get this question a lot from my clients, how much is needed during the day and does it require replenishment after the workout. Does the standard of half your weight in ounces apply?

[Dr Pangloss]

Interesting stuff. I do question and I get this question a lot from my clients, how much is needed during the day and does it require replenishment after the workout. Does the standard of half your weight in ounces apply?


Have them get on the scale before and after the workout. If they're losing more than a pound afterward, they should hydrate more.

[juggernaut]

Thanks doc. Now what about during the day? What's a good ratio to go by? Like I said, I always told people to get in at least half your body weight in ounces. Is that acceptable?