PEM & The Quantum Observer Effect: Can Changing How You Perceive Movement Alter Symptoms?
- FND Health
- 2 days ago
- 5 min read
I've been fascinated by PEM—both through personal experience and my own research. I went from having a physically demanding job and being an active, sporty person who thrived on exercise and challenges to a state where even minor movements—rolling over in bed or walking to the bathroom—sent my heart rate soaring. But the full force of PEM didn’t hit immediately. Hours later, the symptoms would crash down, leaving me battling both physical and neurological fallout. Years of this left me searching for answers.
Once I understood that Post-Exertional Malaise (PEM) is the nervous system’s response to a perceived stressor, everything clicked. The autonomic nervous system (ANS) reacts instinctively to stress—exertion being one of them—but in its hypersensitive state, it was overreacting to even the smallest exertion.
What if, over time, we could train it to respond differently? This isn’t about willpower; it’s about retraining the nervous system itself.
"Post-exertional malaise (PEM) is a delayed worsening of symptoms that occurs after minimal physical or mental activity" https://www.hopkinsmedicine.org
So that’s exactly what I set out to do. Over the last year, I’ve been retraining my nervous system to react differently, and the improvements have been remarkable.
This post takes a deep dive into PEM, drawing from my own findings and lived experience.
What if PEM isn’t just about what we do, but also about how we perceive what we do?
We’re told to pace carefully, track our limits, and avoid pushing too hard—but what if our perception of movement plays a bigger role in triggering PEM than we realise?
It might sound radical, but quantum mechanics offers an interesting framework to explore this idea.
The Quantum Observer Effect: Reality Changes When You Measure It
In quantum mechanics, there’s a strange phenomenon known as the observer effect. The famous double-slit experiment showed that when particles like electrons or photons aren’t observed, they behave like waves—existing in multiple possibilities at once. But as soon as they are measured or observed, they “collapse” into a fixed state, acting like solid particles.
In simple terms, the very act of watching something changes its outcome.
Physicist Erwin Schrödinger’s thought experiment with his famous cat takes this even further. A cat in a sealed box, under a quantum rule set, is both alive and dead until someone looks inside. The moment it’s observed, it settles into one state or the other.
This sounds bizarre, but the key takeaway is this: in the quantum world, things exist in a fluid, flexible state until we observe them—and then they become fixed.
How PEM Acts Like a Quantum Phenomenon
What does this have to do with PEM? More than we might think.
If we approach movement with fear, monitoring, and expectation of PEM, we are effectively “measuring the particle.”
We turn movement into an observed task, locking it into a rigid state where exertion becomes stress, and stress triggers PEM. It’s as if the body wasn’t necessarily going to crash, but because we monitored and analysed our exertion, the nervous system responded accordingly—collapsing into PEM just like the quantum particle collapses into a fixed state when observed.
On the other hand, if we engage in movement without focusing on it as exertion, simply enjoying a walk, laughing with a friend, or getting lost in the moment, the nervous system doesn’t react in the same way. The “wave” stays uncollapsed. Movement remains fluid, not something that has to result in PEM.
Changing the Way We Perceive Movement
If PEM is influenced not just by what we do, but by how we observe what we do, then shifting our perception could be a powerful tool in recovery. Here’s how:
1. Reframe Movement: Instead of seeing activity as “exercise” or “something to manage,” shift the focus to enjoyment. A walk isn’t exertion—it’s a chance to connect with nature or a friend.
2. Reduce Fear & Monitoring: The more we track, measure, and anticipate a crash, the more likely our nervous system will react accordingly. Let movement be an experience, not a test.
3. Engage in Presence: The more present and absorbed you are in what you’re doing, the less likely your body is to interpret it as exertion. Fun, laughter, and flow-state activities can be protective against PEM.
4. Trust the Process: Like in quantum mechanics, possibilities exist until they are observed. If you focus on movement as something natural and enjoyable rather than something that needs to be controlled, your body may respond in a way that allows you to do more without the same crash.
A New Perspective on PEM
The idea that our perception of movement influences how our body reacts isn’t just philosophical—it’s deeply rooted in how the nervous system operates. Just as quantum mechanics suggests that observation shapes reality, the way we mentally frame activity may shape how our nervous system responds to it.
This doesn’t mean PEM is “all in your head.” The nervous system still reacts to exertion on a physiological level. However, over time, reframing our thoughts during movement can shift the body's response. By gradually associating movement with safety—even enjoyment—the nervous system may become less reactive.
Of course, this doesn’t mean severe cases can be overcome simply by thinking differently overnight. But it does suggest that the way we engage with movement—moving away from fear, rigid tracking, and stress, and toward presence, enjoyment, and trust—could make a meaningful difference.
I’ve seen this shift first-hand. Over the past year, I stopped focusing so much on the exercises themselves and instead turned my attention to activities that kept me present, things that demanded my full attention and felt rewarding.
And that shift—engaging with movement in a way that felt good rather than something to endure—has helped me progress in ways I never thought possible. I can physically do so much more now, not because I pushed harder, but because I changed the way I approached movement.
Maybe, just maybe, by changing how we observe movement, we can change how PEM affects us.
Research & References
Research strongly supports the idea that PEM is a result of autonomic nervous system dysfunction. Studies have shown that people with conditions like ME/CFS, which feature PEM, experience significant disruptions in their autonomic nervous system. This dysfunction can result in the body struggling to maintain balance after exertion, causing the severe crashes characteristic of PEM (MDPI).
Additionally, research has found that the sympathetic nervous system—the part responsible for the “fight or flight” response—can become overactive during PEM episodes. This can lead to heightened heart rates, stress responses, and other symptoms after even mild exertion. The body's automatic systems fail to regulate properly, causing prolonged fatigue and other issues (Neuroregulation.org).
In simple terms, PEM is a nervous system disorder—one that involves a hyper-reactive autonomic nervous system that over-responds to exertion.
Schrödinger’s thought experiment (Wikipedia) provides an interesting lens through which we can understand how perception and reality are intertwined, much like how our perception of movement might shape PEM responses.
References
Wheeler, J. A. (1983). Law without Law. In J. A. Wheeler & W. H. Zurek (Eds.), Quantum Theory and Measurement. Princeton University Press.
Zeilinger, A. (1999). Experiment and the Foundations of Quantum Physics. Reviews of Modern Physics, 71(2), S288-S297.
Schrödinger, E. (1935). Die gegenwärtige Situation in der Quantenmechanik. Naturwissenschaften, 23(48), 807-812.
D’Agostino, R. (2021). The Role of Perception in Chronic Illness and the Mind-Body Connection. Journal of Psychosomatic Research, 145, 110478.
Van Oosterwijck, J., Meeus, M., Paul, L., et al. (2013). Pain Inhibition and Post-Exertional Malaise in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome: An Experimental Study. Journal of Internal Medicine, 274(5), 486-493.
Kluger, B. M., Krupp, L. B., & Enoka, R. M. (2013). Fatigue and Fatigability in Neurologic Illnesses: Proposal for a Unified Taxonomy. Neurology, 80(4), 409-416.
