In last week’s post I spoke about the importance of finding a good stress balance as the first step in building a strong foundation for our nutrition and fitness goals. You learned last week that stress is neither good nor bad, and that we need to find the right balance of stress for us to thrive, grow, and be healthy.
If you have been reading my content for any period of time you know that I think understanding what is happening in our bodies can help us make connections to how our environment is impacting us. Stress is not that different from any other environmental influencer in that it influences lots of different processes in our bodies. Let’s take a look at what changes happen in our bodies as we experience various different degrees of stress.
Our response to stress all begins in the brain. When some kind of event takes place, that event is perceived by your body’s sensory receptors such as hearing, eyesight, smell, touch…etc. The information received by your sensory receptors is then interpreted by your brain. Your brain’s response to those inputs then will dictate whether you have a stress response or not.
This is a very important concept to understand when it comes to stress…it is YOUR interpretation of the event that dictates whether you have a stress response.
If you come across a snake on your hike but you are not scared of them, you may stop and just walk around the snake and keep on moving as if it was a cute puppy.
However, if you have an extreme fear of snakes, you might stop and run in the other direction!
This is an extreme example of different responses to the same event but it illustrates the point nicely.
The good news is that since your brain is the one interpreting the information and determining whether the event is stressful or not means you may be able to change your response over time…more on this later.
If your brain determines the event is stressful how does our body respond?
Let’s return to our snake example.
If you are very afraid of snakes and your brain perceives it as a stress then your body is going to want to do one of two things
In other words it’s going to prepare you to fight and defend yourself from the snake or it’s going to prepare you to run away and escape. In either case they both cause very similar things to happen in your body.
It starts with the brain sending a message to the pituitary gland at the base of the brain causing it to release a hormone called ACTH. ACTH is picked up by the adrenal glands and causes them to release two other hormones called cortisol and adrenaline. You have probably heard of cortisol and adrenaline before These two hormones are what causes you to feel alert, excited, and a sudden surge in energy.
The reason these hormones make you feel that way is because of the effects adrenaline and cortisol have on different parts of your body…they are priming your body to fight or run away.
When these two hormones enter your bloodstream your breathing rate, your heart rate, and your blood pressure will all increase. In addition the liver will start to convert stored glycogen into glucose so that it can be used for fuel by your muscles.
All of these things make sure you have the necessary oxygen and nutrients needed by your muscles to contract quickly and powerfully for the forthcoming fight or escape attempt.
In addition your body is going to stop spending energy on non-critical functions. Your body will for example stop the digestive processes in order to prioritize energy and nutrients for the threat at hand.
In addition your senses will become heightened focusing on the stressful situation at hand. In this case your vision will become focused on the snake to make sure you know exactly what the animal is doing. This same thing can happen to your hearing, where you only focus on any auditory information coming from the stressor. You might not notice things that are happening around you when this happens.
The acute stress, like seeing a snake, and the subsequent flight or fight response from the body is not a bad thing. In fact it is life saving in some cases. The effects of the stressor are generally over quickly and we can return to baseline. As long as these acute stressors occur few and far between, we can usually handle them.
Chronic stress, stress of a lesser intensity but persists for a long period of time, is a much greater problem. Chronic stress also activates our flight or fight response but to a lesser degree. The difference is that chronic stress never allows us to return to baseline.
As we can see in the diagram below, the constant activation of our stress response system can lead to a host of health problems. I would love to elaborate on how all of these health problems can stem from chronic stress, but each one could be its own post. The (very) simplified explanation though is that the physiological changes we discussed above from an acute stressor stay activated all the time. In the short term those physiological changes are life saving, however you know things like a high heart rate, high blood pressure, elevated glucose, poor digestion are all bad things if they are chronic. Chronic stress turns all these things on, but never gives us a chance to shut them off.
In addition chronic stress tends to create a vicious cycle or a better term would be a negative feedback loop.
The chronic stress itself not only can lead to disease states, but it also leads to poor lifestyle behaviors. This is another reason why chronic stress is worse than acute stress. Again, acute stress is over relatively quickly and we return to our baseline. Chronic stress persists and so we try to find ways to alleviate the stress.
What do I mean by this?
Stress makes us uncomfortable and we don’t like being uncomfortable, so we find ways to make ourselves comfortable again, we are seeking a way to return to baseline..
Have you ever heard of stress eating?
I am sure you have, and I am sure everyone has fallen victim to it before….I know I have.
Food provides us comfort…particularly highly processed foods. When we are stressed we are more likely to eat foods that might make us feel better in the moment but probably are not good for us long term and do nothing to address the reason for the underlying chronic stress .
To add more insult to injury, the food we consume when we are trying to comfort ourselves can further exacerbate problems already caused by chronic stress. As you can see above one of the negative impacts of stress can be digestive issues. Now layer on top of that a solid dose of processed foods, do you think that helps their digestion?
Now the worsening digestive issues are adding to our chronic stress.
This cycle continues over and over again.
Another lifestyle factor impacted by stress is sleep. When we are stressed about the latest devastating news, the person on social media who is trolling you, the piles of work that are accumulating, your dwindling savings account, how do you think you are going to sleep?
Not so good!
Again the negative feedback loop is present here as well. Now you are stressing about the poor sleep you are getting!
In terms of physical activity, acute stress can be a positive thing. Think of a set of all out sprints. This is a highly stressful event that is over quickly but can result in a host of positive outcomes. Chronic stress on the other hand can have the opposite effect on our physical activity. When we are chronically stressed we are spending our energy elsewhere. Our body is always in a heightened state and it’s working hard to deal with the perceived threat. This means we are going to have less energy to spend on physical activity, whether that be going for a walk or a formal workout .
By understanding how stress changes our bodies, behaviors, and lifestyle I hope you can now begin to see why if you have poor stress management practices your fitness and nutrition goals will suffer.
With this understanding of how stress is impacting us we can now have a discussion about what we can do to improve our ability to deal with stress and even find ways to handle more stress when life demands it. The next blog post in this series will address how to do just that. If you would like to be notified when the next blog post is ready, sign up for my newsletter using the form below. Whenever I publish new content I will email you a link so you can stay up to date with all the actionable information I put out to help you achieve your goals!
- (2021, May 29). The Use of Self-Help Strategies in Obesity Treatment. A Narrative …. Retrieved June 8, 2022, from https://link.springer.com/article/10.1007/s13679-021-00443-z ↑
- (n.d.). The Effects of Stress on Physical Activity and Exercise – PMC – NCBI. Retrieved June 8, 2022, from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3894304/ ↑