Running: Protect Your Adrenal Function

As the last entry discussed, the adrenal glands are subject to stress during training. This is perfectly acceptable if you have healthy adrenal status. But if you have some level of adrenal fatigue, you must be prepared to train wisely. If the idea of "adrenal fatigue" sounds a little strange to you, we should describe it more accurately as "hypothalamic-pituitary-adrenal axis dysfunction." This is the biological system that regulates adrenal activity and is commonly referred to as the HPA axis.

HPA dysfunction is common and is related to multiple symptoms.

1. Chronic fatigue. Psychosomatics 2008 Sep-Oct;49(5):450.
2. Irritable Bowel Syndrome. Neurogastroenterology & Motility 2009 Feb;21(2):149-59. Epub 2008 Aug 5.
3. Altered immune function. Journal of Neuroimmunology 2002 Dec;133(1-2):1-19.
4. Depression Psychological Medicine 2009 Apr 1:1-4.

If you already have some level of HPA dysfunction, then aggressive training may actually harm your health. This doesn't mean that you shouldn't run at all. Interestingly, low intensity exercise reduces burden on the adrenal glands. Journal of Endocrinological Investigations 2008 Jul;31(7):587-91.

Because HPA dysfunction is not a "disease" per se, there are no accurate numbers for how many Americans are affected but adrenal health is relatively simple to assess. It involves a simple saliva test that many functional laboratories (i.g. Diagnos-techs, Metametrix, Genova Diagnostics) perform.

If you have experienced a drop in performance, slower race times, slower recovery, gastrointestinal discomfort or fatigue, you may be overtrained. More on overtraining next time.