Living by the Flow, Revealed by the Stock — Marathons and Systems Thinking

 

We live by flow, but the world sees us by our stock.

Our daily lives are made up of small actions, like moments of differentiation—the small, incremental shifts we make each day. However, the world judges us based on the accumulation(integration) of those actions. Indeed, the result of integration is what shows up as me: my health, my reputation, my relationships, and my life.

We Act in Flows, but Get Judged by Stocks

In systems thinking, a flow means the rate of change over time, and a stock is the accumulation of those changes.
For example, when we step on a scale, we see our body weight—a stock. But that weight is created by the daily flow of our eating and exercise habits.

Here’s the catch: stocks don’t change instantly.
Even if we start a new habit today, the results don’t show up right away. There is a delay—and not just a simple one. The effects don’t always match the size of the change. Sometimes they’re not even proportional, and at times, the results can seem paradoxical. That’s why systems thinking helps us understand such delayed and nonlinear feedback.



Systems Thinking on the Marathon Course

I experience this every time I run a marathon.
At 20km, 25km, and beyond 30km, I feel the “integrated result” of all the training and energy I’ve spent so far.
Each moment, my heart rate—a flow—changes, and that flow indirectly contributes to the physical condition of my body—a stock. Heart rate is not the direct flow that fills or drains the stock of my physical condition, but it strongly influences the flows, like fatigue, hydration, or muscle stress, that do. The surprising part is that I don’t notice the stock changing right away. When my body starts sending warning signals, it’s often too late.

I used to treat running without stopping like a badge of honor. When I passed runners walking in exhaustion, I felt a quiet mix of sympathy and pride—sorry for them, but secretly pleased that I was still running.

It was like I was caught in a reinforcing loop:


"Trying to keep running" → "Feeling of capability"(+) → "Level of performance"(+) → "Trying to keep running"(+).

But this reinforcing loop, though motivating at first, blinded me to the signals my body was sending. It pushed me toward performance at the cost of sustainability.

To make matters worse, after a race, I saw even experienced runners getting injured—fluid in the knees, acupuncture, and severe fatigue. It made me stop and ask:

“Is this really a healthy system?”

That’s when I made a promise to myself:


Stop chasing time records. Instead, slow down if I need to, and listen carefully to my body—for the sake of lasting health.

The Law of Total Pain— Is It Real?

I used to believe in something I called “the Law of Total Pain”:
No matter how fast or slow you run, the marathon demands a certain level of pain and fatigue. So it was up to each runner to decide:

  • Would you get the pain over with quickly by running fast?
  • Or stretch it out more gently by running slowly?

I chose to run slowly, not just for comfort, but to step away from the obsession with time records.

But after some intense group training for the 2025 Paris Marathon, I found myself more exhausted than expected. That made me ask a deeper question:

"What if the Law of Total Pain isn’t a law of nature, but just a mental model I had accepted?"

Maybe it’s not just about redistributing pain.
Maybe adding a new kind of flow, like recovery, can actually shift how the entire system behaves.

Experts say that taking short breaks can improve the body’s overall efficiency. Brief pauses help flush out lactic acid, slow glycogen depletion, and allow the heart rate to recover. When the heart rate drops during a break, the cardiovascular system works better in the next phase.

Instead of focusing only on the outcome—the stock—we can learn more by paying attention to the flow. Observing how the body responds in the moment gives us new insight and helps us make wiser decisions.

In my case, pausing for two minutes at a water station to catch my breath and lower my heart rate felt like a small choice, but I belive it could turn out to be a high-leverage action that helped my system stay intact and finish strong.

I haven’t applied this in a real race yet, but I’m planning to test the idea in my next marathon. It’s still a hypothesis, and I’ll keep observing whether this flow of recovery truly supports system integrity.

My Condition Is the Result of Integration, but the Essence Is in the Flow

Every moment, we make a decision and take action in the flow of our lives. These moment-by-moment choices shape our lives, but people often overlook them. Instead, they focus only on the outcome, the stock, not the flow that created it.

They ask, “Why are you still like this?” or “Why haven’t you improved?”
They look at the result, not the direction of the flow that created it.

But systems thinking tells us:

“What really matters is the direction of the flow.”

What kind of flow did I choose today?
What stock is that flow building?
And do I understand the delay between the two?

We must ask these fundamental questions to take care of our bodies and lives.

๐Ÿ’ก Conclusion: To Manage Your Stock, Care for Your Flow

We all grow older. Aging is something we’ll all experience, and it shows up as a stock. But that stock is shaped by the quality of our daily flow:

 How we breathe, move, and recover—day by day.

Just like having the courage to pause during a marathon, slowing down sometimes and choosing recovery in life is the real systems thinking strategy for living longer, deeper, and healthier.

So maybe a sustainable life is about sensing the flow, and caring for the stock it creates.


(After Marathon)
Thanks to my planned rest strategy, I was able to complete the full course of the Schneider Electric Paris Marathon 2025 without accumulating too much fatigue. As for my finishing time… well, that’s classified information. ๐Ÿ˜‰
 

Comments

Post a Comment

Popular posts from this blog

Thinking in Systems Guide (1) – Preface

Image
   The Beginning of Systems Thinking: A New Lens on the World Taught by a Slinky "If a factory is torn down but the rationality which produced it is left standing, then that rationality will simply produce another factory." - Robert Pirsig (Here, “rationality” can be understood simply as the reason or purpose behind it.)   Why do we always face the same problems? Have you ever had this experience? You worked hard to solve a problem at work, but before long, a similar issue appeared again in a different form. Or you may have tried to break a bad habit, succeeded for a while, and then suddenly found yourself back at square one. These kinds of repetitions happen because we focus only on the symptoms of the problem. The true cause—the underlying structure —remains untouched. The Slinky Experiment: The First Insight of Systems Thinking Donella Meadows, who taught system dynamics at MIT, often conducted a fascinating classroom experiment. She used nothing more than a Slinky—t...
Read more

The + and - Symbols: Simple Enough for Elementary Students, Yet the World's Most Confusing Concept

Image
Let me talk about the most challenging concept in the world—at least for me. It’s so simple that even elementary school students understand it. But believe me, it gets you when you least expect it. I’m talking about... + and -. And yes, there’s a twist. Actually, there’s a twist to the twist—so buckle up.  In my systems thinking lectures, I typically explain that when cause and effect move in the same direction, we use the + symbol and refer to it as a positive causal relationship. When they move in opposite directions, we use the - symbol and call it a negative causal relationship. I always emphasize firmly that "positive" and "negative" here are purely mathematical concepts—they have nothing to do with good or bad. Elementary School Level   For example, when the birth rate increases, the total population also increases. Since both birth rates and population changes move in the same direction, we write:  Births → Population (+)  Conversely, when the death rate incr...
Read more

[The Electronic Oracle] ③ Assumptions Aren’t "Guesses": A Proposal for Transparent Democracy

Image
  [The Electronic Oracle] ③ Assumptions Aren’t “Guesses”: A Proposal for Transparent Democracy When I teach System Dynamics or computer modeling, I often encounter a word that instinctively annoys both students and practitioners: "Assumption." The dictionary reveals the source of this discomfort. Assumption :  “a thing that is accepted as true or as certain to happen, without proof .” (Oxford Languages) For scientists, the phrase "without proof"  can sound like an insult. So when someone says, “That’s just your assumption,” scientists rush to defend themselves: "No! I have evidence!" In this post, I want to restore the honor of this word. Modeling assumptions are not mere tricks to patch missing data; they are influential political acts that transform secret dictatorships into transparent democracies. This article distinguishes two layers of assumptions: The Assumption as Belief (Type A)   hides in the mind and operates on authority The Model Assumption (T...
Read more