Stress - Response
The primary purpose of running is usually to have fun and to add value to our lives in some way. When we talk about specific workout designs, we’re usually talking about performance, which is improvement in capacities (body/physiology) and abilities (craft/skills).
When we think about designing a workout to improve performance at a future date, we need to appreciate that the improvements in capacities manifest following relevant adaptations in how cells function in terms of structure, metabolism, maintenance of homeostasis, and communication with other cells. These adaptations occur at the cellular level but have complementary, synergistic, and even emergent benefits for performance beyond the cellular level, to include the organ, organ systems, and organism (whole body). In this way, workouts - a term I use to encompass all planned and structured exercise - are tools for stimulating those changes.
There's a great deal we still don’t understand about how the act of running drives changes to our physiology. The traditional notion of the clinical stress-response (General Adaptation Syndrome) is unlikely to be accurate in the way that it’s long been co-opted by the sports world. Rather, we’re now gaining a much greater appreciation for the nuances of context. The physiological and psychological state within which we perform our workouts appears to have a very large affect on the features - and outcomes - of the stress response that dictate our recovery and adaptation patterns.
In the traditional concept of clinical stress-response, the idea was that we stress a function or capacity to near it’s limits and there will be a stereotypical response. That stereotypical response, by definition, would be the same every time in the classical model. This concept was first proposed by Hans Selye. As I understand it, his work was never meant to apply as broadly and into other fields as it has been adopted. He was studying major and fundamental stress-response patterns such as fear or trauma and the resulting adrenaline or inflammatory responses, for example. He was not studying stress-response patterns associated with daily activities and improvements but rather the fundamental patterns intrinsic to survival. It’s not a stretch then to propose that there is no true historical origin of the most commonly held beliefs in exercise training that assume a reliable and specific adaptation to a specific workout - do this workout and get that result - is too simplistic. The basic principles that underly the majority of exercise training plans owe their origins to a theory of pathological stress-response patterns, which may not be reliable across the spectrum of sports. We now appreciate more than ever that response patterns to insults that threaten health such as disease and trauma are very different from the responses to stresses that promote health.
When we exercise, the stress we impose does not require survival responses. It’s true that some facets of the same processes may be engaged - e.g., specific features of inflammation - but it’s a misunderstanding to think of these very complex systems functioning similarly in health damaging and health promoting contexts. Because physical exercise does not threaten our immediate survival, our body's responses to workouts did not evolve the power to activate stereotyped survival mechanisms regardless of the subtle conditions of our internal environment. For example, regardless of whether you're happy or sad and whether it’s morning or midday or evening, you will have a massive surge of adrenaline if you're in a car crash. Your body's hormonal state, cellular circadian rhythms, metabolic substrate availability, core temperature, hydration level, and myriad other variables will have little or no effect on that adrenaline surge. Now let’s imagine that you did not get in a car crash but rather made it to the trailhead and had a nice workout. All of those internal factors that didn’t matter for your body’s response to the car crash do impact how your body experiences the stresses of your workout, which modulates both the stimulus the workout provides and the eventual adaptations to your workouts. In effect, no two workouts are viewed by the body identically even if they appear identical on paper. Sometimes the differences are small and negligible. Other times, the differences may be as big a factor - or even larger - than the actual workout stimulus. If you’ve been sick with the flu for three days, you’re underfed and dehydrated, you barely slept last night…do you think the stimulus and responses to a 45-minute run at a given pace will be the same as it would if you were happy and healthy? Of course not.
So, we must always bear in mind the physiological environment within which we impose a workout so that we can produce the desired stress and, hopefully, reap the benefits of the desired adaptations, which also require attention to our behaviors such as sleep and nutrition during the recovery and adaptive period of hours to days after the workout.
You can put these modern concepts into action by following some basic steps.
Make a note about each planned workout that describes the intended stress or stimulus of the workout.
Make notes each day about how you are feeling and your overall sense of energy, motivation, and happiness.
Consider the notes about how you feel in light of the stresses in your life and make note of those, especially in the categories of: sleep, hydration, nutrition, sickness or injury, workouts, social/family and work life, to identify patterns and causes.
Review the plan for the coming days along with the associated note on each workouts intended stress or stimulus, and make adjustments to the factors in step 3 or to the planned workout that are consistent with getting the intended stress. The adjustments might be more or fewer intervals, longer or short durations, more or less elevation change, altering your diet, drinking more water, spending extra time with family the evening before a long run, asking a friend to join you on a run, telling your friends you want to run by yourself this Friday, or taking a nap…that’s one most of us could do more often.
Notice that I didn’t recommend using any technology or devices to inform you of physiological values that might reflect your bodies internal environment. There are two reasons for this. First, the environment I’m talking about has thousands of variables and the inclusion of any 1, 2, 3, or even 10 into your process is going to introduce excessive bias. With deliberate attention and practice, your brain is the ultimate integrative sensor that will give you the most reliable and valid quantifications you need. Second, few (perhaps none) of the measurable, non-clinical variables have definitive validity in practice for athletes.
Appreciate that many of your actions and thoughts play significant roles in your long term abilities as a runner. The actual runs you go on are just one factor and they must work with all the other factors, not in spite of them. Those other factors set the physiological and psychological environment within which your cells and organs are stressed by workouts and thereby modulate the actual stresses you create during that run and in the period of recovery and adaptation after it. Your body doesn’t experience a 6-minute interval the same on any two days because you are not identical on any two days.
This is some of the reason I end every episode of SOUP by reminding you that how you eat, sleep, think, and move all play a role in helping you become your ultra best.