Massive shout out to Dave Mayo of Synergy Health and Wellness for contributing his time and genius to further developing strategies of wellness for all members of The Movement Program at Steelworks CrossFit. Below you will find Dave’s work on what stress is and just how nasty it is at preventing you from really big squats, explosive second pulls on the snatch, and just plain good living. The author also provides some really simple, but effective strategies for dealing with stress.
Let’s talk about stress, baby!
Stress is something that every person on the planet has heard of but few people understand. If I were to list the 2 most important things every person should understand about health, stress would be one of them along with epigenetics. Stress is so fundamental to life that every animal on the planet has a system to deal with it. In humans and all vertebrates, the stress response is handled by the HPA (Hypothalamus, Pituitary, Adrenal) axis. Before we go in to depth on the HPA axis, let’s define stress and what it does.
What is stress and how is it dealt with?
Stress is defined as an organism’s response to an environmental condition or stimulus (1). When an organism is presented with a change in environment that requires a response, the HPA axis is activated to prepare the organism for that condition. Probably the most familiar image would be of someone walking through the woods stumbling on to a tiger. When this person sees the tiger, the Hypothalamus begins secreting CRH (Corticotropin Releasing Hormone) and vasopressin which stimulate the pituitary to secrete ACTH (Adrenocorticotropic hormone). ACTH then makes it’s way to the adrenal glands to signal them to start producing cortisol, one of your primary stress hormones. Cortisol is a glucocorticoid, meaning its primary role is to help increase blood glucose by causing the liver to release it’s stored glycogen. Cortisol then feeds back on the hypothalamus, slowing down it’s secretion of CRH and vasopression, which slows secretion of ACTH from the pituitary, which slows down secretion of cortisol. While this is good information, it’s not the part about stress that most people should pay attention to, it’s the effects of chronic stimulation of the stress response that it important.
So what does the stress response do?
The entire purpose of the stress response is to partition resources so that you are better equipped to deal with stress when it comes along. This is done via the autonomic nervous system. The autonomic nervous system is the master processor of all of your automatic processes such as breathing, heart rate, blood pressure, digestion, immune system function, etc. The autonomic nervous system has 2 branches, the sympathetic and parasympathetic, seen below.
Taken from: http://users.rcn.com/jkimball.ma.ultranet/BiologyPages/A/autonomic.gif
Looking at the functions of each branch of the autonomic nervous system, you may see a pattern. The sympathetic nervous system is also referred to as fight or flight and is what activation of the HPA axis is all about. By increasing heart rate and blood pressure while diverting blood flow from the organs of digestion to the muscles, you are partitioning your resources to get the hell out of there or kill whatever you come in to contact with. Once you have accomplished that task, the parasympathetic nervous system comes in and shifts you towards what is known as rest and digest. This helps you recover from the stressor that you were just exposed to. This is how the stress response evolved, and this is how the stress response works best: a short exposure to stress followed by recovery from that stress. The problem is, this isn’t how our current environment works.
Physiological or psychological stress: It’s all the same
Your stress response occurs in exactly the same way whether your stress is from seeing a lion or your stress is from wondering how you will make your next mortgage payment. The amygdala, a portion of your brain responsible for emotional responses, has a direct connection to your hypothalamus and can activate the HPA axis in quick order. While the stress is handled in the exact same way, the effects of both are not the same. In the flee from the tiger scenario you are exposed to a stressor, you exert a ton of energy and force to get away, and then the stress is resolved one way another. Hopefully you made it out alive, but if you died the stress is resolved, regardless.
In the second scenario, you exert no force and the stress is there for as long as it takes for you to figure out how to pay the mortgage. This is normally a much longer exposure to stress and if you experience it one month you will probably experience it the next. Chronic stress eventually impairs your ability to recover from stress because you are constantly in a more sympathetic state (More sympathetic nervous system activity) which impairs your ability to recover from this stress. In addition, since you are activating the sympathetic nervous system more you are activating the parasympathetic nervous system less, meaning you won’t recover because you are not going in to rest and digest mode enough to do so. This also has a major impact on digestion which can cause problems with nutrient absorption and possibly induce irritable bowel syndrome. The link between stress and IBS is fairly well established in the research.
Chronic stress and the immune system
As you go further down the hole of chronic stress, your immune system becomes suppressed because in a state of stress immunity isn’t necessary, that’s handled with rest and digest. Probably the best explanation I have heard about this effect is from Bruce Lipton in his book The Biology of Belief. In it, he describes the HPA axis as a way of partitioning resources where the stress response is in charge of dealing with invaders in the external environment while the immune response is responsible for dealing with invaders in our internal environment. You can’t be better suited to deal with both at the same time, so when you are better suited to one you are automatically less well suited to deal with the other. This is actually a fairly well established fact. When a transplant patient receives his or her new organ, they are given glucocorticoids to suppress their immune system and prevent it from attacking the new organ. Anyone who has ever received a cortisone shot knows the anti-inflammatory effects of this wonder drug. Hydrocortisone is synthetic cortisol and used to suppress inflammation that occurs as a part of the immune response.
Stress is cumulative, deal accordingly
All of your stress in life is cumulative. Whether it’s stress from your missed mortgage payment or training stress from exercise, it has a cumulative toll on your body and should be managed. If you are having a lot of stress from school or work, you more than likely need to cut back your gym time or running mileage. Managing stress begins with good eating and sleeping habits. A poor diet can induce more stress on your body and sleep is how the body recovers from stress. As such, getting less than the required amount of sleep will increase stress. This has been shown empirically in numerous clinical research studies with higher cortisol levels in people who don’t get enough sleep.
Another good stress management tool is mindfulness. Mindfulness meditation is a good way to begin practicing mindfulness and studies have shown reduced brain activity in the amygdala both during meditation and when not meditating in people who underwent an 8 week mindfulness meditation program (2). This appears to work by improving information processing in the brain, redirecting information away from the amygdala and toward the neocortex, the part of the brain responsible for conscious thought and rational thinking.
Being aware of stress and managing it is crucial to optimal health. Whether your stress is mental or physical, your body deals with it in the same way. Too much stress can wreak havoc on your body by negatively impacting digestion, immunity, and quality of life. Getting good sleep, eating right, and practicing mindfulness are all great ways to help keep stress levels under control. It is also important to vary training intensity and volume based on how stressful your life is at the current moment.
Dave Mayo www.synergyhw.blogspot.com