Stress and epigenetics

I've written previously on the concept of epigenetics, the study of gene expression.  We know that for all intents and purposes, your genes do not change.  However, the little signals that tell your body when to express those genes (epigenetic signals) can be altered.  Food certainly has a powerful role in this although we do not understand all the details.  A recent paper also demonstrates that chronic stress will alter epigenetic markers.

Researchers at the Johns Hopkins School of Medicine found that the markers on genes were different after mice were exposed to stress hormones.  They believe that this may have a significant role in the development of  mood disorders.  Notably, the changes were found to be long lasting.  The epigenetic changes were presents for weeks even after the hormones had been removed from their environment.  In other words, these are potentially long lasting epigenetic changes.

 

"These behaviors, which were probably advantageous earlier in evolution, aren't as useful today with modern stressors that we can't fight or flee, such as work deadlines, Potash adds. Consequently, chronic stress might instead lead to depression or other mood disorders triggered by epigenetic changes."

I spend a lot of time talking about the benefits of eating good food.  But total health requires a life style adaptation as well.  Some people believe they thrive when under pressure; we even take pride in it.  Nobody can argue that some individuals genuinely do well under chronic stress. However, we must understand that your performance (at your job, school etc.) does not necessarily correlate with your well-being.  Chronic stress comes with a price.  Much of it has been well described (HPA dysfunction, hypercortisolemia etc.) We now have evidence that even your DNA expression may be altered by stress.

Running: Overtraining- Prevention 2

Eat good food, sleep well and hydrate well. These are no-brainers when it comes to prevention of overtraining syndrome. A good multivitamin & fish oil are also good additions (this is true even for non-runners). But one important nutritional supplement seems to be especially significant; phosphatidylserine.

Let's look at some of the evidence supporting the use of phosphatidylserine.
" The findings suggest that phosphatidylserine (PS) is an effective supplement for combating exercise-induced stress and preventing the physiological deterioration that can accompany too much exercise. PS supplementation promotes a desired hormonal status for athletes by blunting increases in cortisol levels." Journal of the International Society of Sports Nutrition 2008 Jul 28;5:11.

"This is the first study to report improved exercise capacity following phosphatidylserine supplementation. These findings suggest that phosphatidylserine might possess potential ergogenic properties." Medicine and Science in Sports and Exercise 2006 Jan;38(1):64-71

"...chronic oral administration of phosphatidylserine may counteract stress-induced activation of the hypothalamo-pituitary-adrenal axis in man." European Journal of Clinical Pharmacology 1992 April; 42 (4):385-388
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In the world of sports nutrition, there are many supplements and research studies that show benefits of various agents in improving sugar metabolism, energy production, fat breakdown, other variables that can aid performance (creatine, carnitine, ribose to name a few). Phosphatidylserine is worth consideration because of its ability to regulate hormones shifts by stabilizing the HPA axis.

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.