By Jeff Rocco, MD


As an active athlete are you feeling tired and rundown?  Are you working harder, but going slower?  Don’t feel like training?  Feeling moody?  Getting sick?  Losing muscle, and storing fat?  If you are experiencing these symptoms, you may have chronic elevated cortisol levels due to overtraining syndrome (OTS).

As the heat goes up this time of year, so do the density and intensity of race schedules.  The stresses of racing and training are building, and many athletes are wondering if they are experiencing OTS.  Chronically elevated cortisol levels may indicate an athlete is experiencing OTS.

Chronically Elevated Cortisol

Cortisol is a powerful hormone that is produced in the adrenal glands positioned on top of your kidneys.  Its primary role is to mobilize your body’s nutritional resources in stressful situations.

In short bursts, elevated cortisol is good because it elevates blood sugar levels to improve brain function and to prepare the body for action.  Cortisol levels typically increase in the early morning hours before waking.  This prepares your brain and your body for waking activities and helps get you out of bed.

Ironically, when this response is prolonged, memory and mental function are impaired (Taverniers 2010).  Cortisol levels increase in response to physiologic and mental stresses.  In conjunction with the release of epinephrine, many people refer to this as the fight or flight response.  Athletes typically experience this feeling on race day.  Cortisol’s role is to mobilize stored carbohydrates, catabolize proteins into glucose, and to mobilize stored fats.  Your body can use these nutrients to deal with the stressor, whether it’s a race or a saber-tooth tiger.

Chronically elevated levels of cortisol have a number of undesirable effects for athletes.

Fat stores go up Elevated cortisol levels lead to a perpetual catabolic state where muscle is broken down, and fat is stored. 

These effects are exacerbated when an athlete is depleted of carbohydrates.  One key reason why training while fasting is not recommended.  Supplying adequate carbohydrates during training protects against elevated cortisol levels.  Carbohydrates provide fuel for an athlete’s body to do work.  Because your brain requires glucose to function, when your body is starved of fuel, it will cannibalize lean muscular tissue to provide glucose for the brain.  The brain can only function on glucose and is not capable of metabolizing fat.  And while muscular tissue can be broken down into glucose, stored fat cannot be converted to glucose.  It would appear to be common sense that your body will experience less stress from training and racing if it has the nutritional building blocks it needs to repair and regenerate.

Suppressed Immune System

Chronically elevated cortisol levels which are associated with overtraining lead to suppressed immune system function and reduced exercise capacity.  Sick, injured and slow is no way to conduct your season.

Hormones Out Of Whack

Decreased levels of testosterone in men, and decreased levels of progesterone and estrogen in women may further impair recovery.  While these hormones are usually thought of as sex hormones, they are also anabolic and critically important to help potentiate recovery.

Chronic stress causes both an increase in cortisol and a decrease in testosterone, estrogen, and progesterone.  This can lead to amenorrhea in women, and stress fractures in both men and women. 


As an athlete, if you find your performance decreasing despite your hard training, perhaps it is because of your hard training that your performance is suffering.  Once you find yourself in this downward spiral, stop and take a deep breath. No, really, deep breathing can help to reduce stress. 


Consider your rest and recovery time as an integral part of your training schedule.

A training schedule that incorporates periodization allows time for the body to rebuild, and for cortisol levels to return to a normal state.  For best results develop a plan to mangage all systemic stress including work, lifestyle, diet and lack of sleep.  Even adding several hours of recovery time between exercise sessions can reduce cortisol responses on double session training days (Ronsen et al., 2002).

Modify Your Nutrition

Reevaluate your diet before, during and after exercise.  Providing your body with a recovery drink immediately following exercise can jumpstart the rebuilding process, and make the most of precious recovery time. 

Adaptogens, and Rhodiola specifically, appear to lower cortisol levels and improve the body’s response to the mental and physical stresses of training.  (Olsson 2009, Parnossian 2009, Zhang 2009)  A recent study investigated the effects of Optygen (which contains Rhodiola) in a group of collegiate distance runners over the course of a season.  As expected the stresses of a competitive season lead to a 36% increase in cortisol levels in the control group, while the runners using Optygen actually demonstrated a 26% decrease in cortisol levels. (Creer 2007)  The stress of training leading to chronically elevated cortisol can also have a negative impact on exercise capacity.  A study investigated the effects of Optygen in collegiate distance runners while preparing for the cross-country racing season.  The Optygen group showed a 42% improvement in time to lactate threshold suggesting that the reduction in cortisol leads improved physiological parameters. (Larson 2007)

Your body needs to be stressed to make performance gains, but it also needs time and proper nutrition to make those gains.  Use of adaptogens along with carbohydrate support and some  scheduling savvy may allow you to train harder with better stress management, better performance and better health. 



Creer A. The effect of commercial herbal-based supplementation on running performance during a competitive season in collegiate distance runners:  a pilot study. 2007

Lane AR, Duke JW, Hackney AC. Influence of dietary carbohydrate intake on the free testosterone: cortisol ratio responses to short-term intensive exercise training. Eur J Appl Physiol. 2010 Apr;108(6):1125-31. Epub 2009 Dec 20. 

Larson, K. Supplementation using a commercial herbal-based product (Optygen) may increase running performance in highly trained collegiate distance runners:  a pilot study. 2007

Olsson EM, von Schéele B, Panossian AG. A randomised, double-blind, placebo-controlled, parallel-group study of the standardised extract shr-5 of the roots of Rhodiola rosea in the treatment of subjects with stress-related fatigue. Planta Med. 2009 Feb;75(2):105-12. Epub 2008 Nov 18. PubMed PMID: 19016404.

Panossian A, Wikman G. Evidence-based efficacy of adaptogens in fatigue, and molecular mechanisms related to their stress-protective activity. Curr Clin Pharmacol. 2009 Sep;4(3):198-219. Epub 2009 Sep 1. Review. PubMed PMID: 19500070. 

Ronsen O, Kjeldsen-Kragh J, Haug E, Bahr R, Pedersen BK. Recovery time affects immunoendocrine responses to a second bout of endurance exercise. Am J Physiol Cell Physiol 2002 Dec;283(6):C1612-20

Taverniers J, Van Ruysseveldt J, Smeets T, von Grumbkow J.Stress. High-intensity stress elicits robust cortisol increases, and impairs working memory and visuo-spatial declarative memory in Special Forces candidates: A field experiment. 2010 Jul;13(4):323-33. 

Zhang ZJ, Tong Y, Zou J, Chen PJ, Yu DH. Dietary supplement with a combination of Rhodiola crenulata and Ginkgo biloba enhances the endurance performance inhealthy volunteers. Chin J Integr Med. 2009 Jun;15(3):177-83. Epub 2009 Jul 2

May 30, 2018 — First Endurance

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