Friday, March 22, 2013
But is Cortisol really that bad for the body? What is the role of cortisol in the body? What is its effect with resistance training?
As explained in “Where’s the beef? Meathead!” the endocrine system produces cortisol (glucocorticoid hormone) in a similar manner as the production of Amino Acids by the cortex of the adrenal glands (located above the kidneys). After the translation of the RNA messenger from the cholesterol molecule, the pre-hormone is transferred into the endoplasmatic reticulum (structure inside the cell that synthesizes proteins), where cortisol is produced by the Golgi apparatus. It is considered a steroidal hormone because its chemical structure is similar to that of cholesterol just like the sexual hormones. The release of cortisol is controlled by the brain (hypothalamus-pituitary) which triggers its secretion in response to stress providing energy to overcome metabolic disturbances of homeostasis (equilibrium of bodily functions). It is usually released as soon as it is produced and transported by the blood to control the metabolism of proteins, carbs and lipids (fats) to maintain homeostasis.
There have been studies showing that cortisol reduces testosterone levels during exercise, but this is because they present at similar levels and not because there is less testosterone, so cortisol isn’t always the taboo in preventing you from your results. It just might be your periodization, bad eating habits and lack of recovery methods.
Cortisol and Growth Hormone Responses to Exercise at Different Times of Day. Kanaley et al. J. of Clinical Endocrinology and Metabolism. 2001.
Basic Endocrinology. Taylor & Francis. E-library. 2005
How to measure stress in humans. Fernand-Seguin Research Center. 2007.
Relationship between circulating cortisol and testosterone influence of physical exercise. Brownlee, Moore and Hackney, Journal of Sports Science and Medicine. 2005.