Dr. Mitch Broser
Are you feeling “stressed”? If you aren’t, it’s likely you have been at some point in the last few months. Stress can be good or bad – it can stimulate growth or drive degradation. We hear things like “Chronic stress causes elevated cortisol levels which increases your risk of many health conditions” and “meditation can help reduce stress and improve many aspects of health”. Before proceeding to rant about the goods and bads of stress, we need to clarify one little thing…
What the heck is “STRESS”?
Stress is “a state of physiological and behavioral responses to a stressor with the brain being the critical interpreter of what is stressful.”
Stress is not a tangible “thing”. We can’t see stress crossing the street, or running at us head-on as we’re trying to troubleshoot ‘how to sign on to a zoom meeting’ with our boss. We can’t SEE stress. This makes it difficult to quantify, especially since stress is different for everyone!
Stress is a perception created by our brain. A perception is what we believe to be true based on the information we have collected. The state of being stressed is a product of a perturbation in our external or internal environment. An external stress would be like driving through a snowstorm, whereas an internal stressor would be like an infection or elevated glucose levels in a diabetic person. Stress can come at us from all angles, both from within (poor health) and outside (a bad situation). We can experience stress from finances, relationships, work, pandemics and more. We can also deliberately stress ourselves with exercise and diet; stressors that we seek out to improve our health.
At this point, we’ve only muddied the waters to answer the question. So now let’s part the muddy seas and get a clear understanding of what stress is.
Different situations stress us more than others, and some of us have a higher tolerance for stress. The stress we “feel” at any single point in time is a result of how we have experienced stress in the past, and how we have responded to it. Humans are dynamic systems – ever changing and evolving in a partially-predictable way. How we experience and manage stress today is different from how we experienced and managed it yesterday, and how we will experience and manage it tomorrow. There are too many factors to truly understand and predict how humans respond to stress. We can however conclude that we call experience stress differently
So what stresses us out?
What is a Stressor? A stressor creates stress. It pushes the physiological system away from its baseline towards a lower utility state. Utility can refer to purely a biological perspective (health, survivability and reproductive success) or hedonic perspective (seeking a pleasant experience). So we can say that stress can push us away from health and/or happiness. Being RESILIENT refers to how quickly and effectively we can return to the baseline of health and happiness. Someone with PTSD cannot effectively return to baseline due to the acute overload of stress. STABILITY refers to how well we can maintain our current utility (health or happiness) without being pushed away. As living organisms, resilience and stability is ever-changing as we adapt to stresses and evolve. The movement of the system (health and happiness) is not dependent solely on objective measures of the stressor (because we can’t accurately quantify stress) but also on the individuals’ traits of distress proneness and their perception of the stressor. Allostasis refers to “the dynamic control over these variable perturbations (stresses) for maintaining a functional (healthy or happy) state.
Allostatic load refers to the total stress someone is under and their ability to manage it. It is the utility (health and/or happiness) reduction associated with both change in state and with alteration in the attractor basin (baseline level of health/happiness) that affect system (our body’s) responses following future perturbations (stresses). We can think of stress as having a tax on it – it is the cost to the system due to repeatedly returning to baseline; the physiological cost due to chronic stressors.
We need to understand that stress is multidimensional and cumulative. Let’s use the gas-tank analogy. If we have a full tank of gas, we can drive very far! But we can only drive as far as our gas tank will allow us. If we want to drive further, we need to build a bigger gas tank! Now, stress is a gas-guzzler, kind of like when we rev our engine and drive recklessly. We will burn gas much more quickly and less efficiently. If we burn up gas from stress at work, financial stress, limited sleep, poor nutrition, hard physical activity without recovery, etc. then we will have less gas in the tank and hence cannot drive as far. If we keep running our vehicle (ie body) at high RPMs, it will become less resilient and will break down over time. Adequate stress with sufficient recovery will keep our engine running efficiently and smoothly.
How will this change what we do?
Over the long run, we need to manage stress effectively to improve health and longevity. Understanding that we have a limited capacity for stress, we need to consider all forms of stress equal. For example – you want to run a personal best 10k race. If your body feels that you are already under “stress”, then it’s unlikely you will run your fastest race because you are entering the race with only half a gas tank! So how do we know how much gas we have in the tank?
This is very difficult to answer because stress is multidimensional, dynamic and different for everyone! We can’t say exactly how much stress someone is under, because two of the exact same situations at different times will produce a different amount of stress. One scientific method we can use to monitor stress is to measure HEART RATE VARIABILITY (HRV). HRV is how much our heart rate varies. Our heart is controlled by our autonomic nervous system, which is directly influenced by stress. A heart rate with high variability is healthy because it is an indication that our body is able to adapt to varying stress. A heart rate with low variability means our body cannot respond well when stress varies. Measuring our heart rate variability one time will not give us any useful info. We need to measure HRV consistently over time so we can see “trends”. Trends allow us to see patterns and changes over time. These trends will allow us to learn more about our bodies and how it responds to stress. For example, perhaps you notice changes in your heart rate variability when you get poor sleep, or when work stresses you out. Monitoring these trends will give you a much better understanding of how much stress you are under relative to your baseline, and how much more stress you can tolerate without decrements in health.
How do you track stress?
A great app that we recommend is “HRV4Training”. The app uses your phone camera to measure your HRV through your thumb and keeps data so can see changes over time.
A simpler method to monitor trends is journaling. You can keep a simple daily journal about different types of stress and correlate that with exercise performance or self-rated energy level. It is less scientific, but it’s a great way to start finding trends and understanding how full your gas tank is.
We always start our day by writing down one thing that might stress us out and how our best self would deal with this stress. Anticipating stress allows us to prepare for it and minimize the negative effects on our system.
In conclusion, it is important to consider all forms of stress as equal. We need to understand that we have a certain capacity for stress. Not all stress is bad, but there is an optimal amount of stress that creates positive changes in health and happiness.