The Line Between Listening and Obsessing
A journey into the quantified self 🔢
I got into triathlon the way many people do in their early twenties.
With confidence. With ego. With just enough fitness to be dangerous.
I didn’t ease into it. I dove headfirst.
I signed up for races before I understood training. I stacked workouts because I felt strong. I played hours of pickup basketball post-training sessions. I assumed soreness was just the cost of admission. Rest felt optional. Recovery felt like something older, slower people needed.
I had grown up athletic. I could suffer. I could grind. And I genuinely believed that was enough.
It wasn’t.
Within months, I hit a wall so hard I couldn’t get off the couch.
When I finally got up, workouts that used to feel manageable felt heavy from the first step. My legs had no pop. My heart rate spiked doing things that should’ve been easy. Sleep didn’t fix it. Motivation didn’t fix it. Doubling down definitely didn’t fix it.
I didn’t know the term yet, but it was classic overtraining. Not dramatic burnout. Just a quiet, grinding mismatch between stress and recovery.
And the most confusing part was this:
I was doing more and getting worse.
When effort stopped working
Up until then, I trained on feel.
Hard days were hard because I decided they were. Easy days were whatever I didn’t feel like pushing. There was no structure. No guardrails. Just effort and identity.
That approach works… until it doesn’t.
And when it stopped working, I did what many confused endurance athletes do.
I went looking for answers.
That’s when I found Team in Training, Ed Zerkle, and The Triathlete’s Training Bible.
I signed up to do my first coached program and became an inquisitive student of the game. I was ready to learn!
Heart rate zones weren’t framed as suggestions. They were physiology. They were thresholds.
For the first time, someone and something explained why my “just push harder” strategy had failed.
Learning that my heart had limits before my mind did
The early lesson was humbling.
My aerobic system didn’t care that I was 24. My mitochondria didn’t care that I was motivated. My nervous system didn’t care that I wanted to train more.
The science was blunt.
Endurance performance hinges on thresholds. The aerobic threshold marks the intensity at which fat oxidation and aerobic metabolism dominate. The lactate or anaerobic threshold marks the point at which clearance can’t keep up with production, and fatigue accelerates. In simple terms:
Our body has two important lines when you exercise.
The first line is the easy line.
Below this line, your body can keep going for a long time. It primarily uses fat for energy, and you can breathe and talk pretty comfortably.
The second line is the hard line.
Once you go past it, your body starts making waste faster than it can clean it up. Your breathing gets heavy, your legs feel tired, and you can’t keep that pace for long.
Endurance training is about knowing where those lines are and spending time on the right side of them.
Train too far above those thresholds too often, and adaptation stalls. Hormonal stress rises. Autonomic balance shifts. Performance drops.
This isn’t theory. Decades of exercise physiology research have shown strong relationships among threshold markers, endurance performance, pacing strategy, and training sustainability.
And there I was, living above threshold because it felt productive. No pain, no gain. Right?
So I learned heart rate.
Not in a casual way. In a please save me from myself way.
I tested aerobic threshold. I learned why Zone 2 felt embarrassingly slow. I learned that most of my “training” had actually been gray-zone thrashing.
When numbers became a superpower
Once heart rate clicked, everything followed.
On the bike, heart rate paired with power. Power told me what I was producing. Heart rate told me what it cost. Together, they instantly exposed pacing errors.
On the run, my heart rate kept me from going out too hot. It forced me to be patient early so I could finish strong.
In the pool, it helped explain why, on some days, the same pace felt smooth, and on others, like drowning.
And it worked.
I got faster while training smarter. I recovered better. I stopped living on the edge of fatigue. My confidence returned, this time grounded in physiology instead of bravado.
Heart rate zones gave me something I desperately needed:
Permission. Permission to go easy without guilt. Permission to rest without fear. Permission to trust something other than willpower.
That’s the moment the seed was planted.
Because once numbers save you from yourself, it’s easy to believe:
More numbers will save you even more.
From structure to surveillance
Here’s where it gets tricky.
At first, quantification felt like freedom. But slowly, almost invisibly, it became something else.
I didn’t just train with data.
I started judging days by data.
A workout wasn’t good unless the numbers looked good.
Recovery wasn’t real unless my metrics agreed.
Easy days started to feel suspicious.
I chased precision. I chased optimization. I chased marginal gains long past the point where they mattered.
And the irony?
The more trained I became, the more I obsessed. Because when the gains get smaller, the data feels louder.
This is the pivot point most people miss.
Awareness quietly turns into control. Control quietly turns into obsession.
2019: Entering the modern quantified self
In 2019, I got a Whoop. The Oura Ring would soon follow.
I wasn’t naive. I knew my history. I knew how easily I could slip.
But wearables had evolved. This wasn’t just heart rate anymore. This was the story behind the story:
HRV. Resting heart rate. Sleep stages. Recovery scores.
And there is real science here.
Heart rate variability reflects the balance of the autonomic nervous system. Lower HRV is often associated with stress, fatigue, and illness. HRV-guided training has been studied in controlled trials, with some evidence showing improved aerobic fitness when training load adapts to physiological readiness rather than fixed plans.
So the promise was compelling:
What if my body could tell me when to push and when to back off, in a way my ego couldn’t override?
That question is dangerous if you already like control.
Six years of learning and relapsing
The last six years have been eye-opening for one reason:
Even when you know the trap, you can still step into it.
There were seasons where wearables helped me:
I saw how alcohol wrecked my sleep even when I “felt fine”
I stopped pretending short sleep was sustainable in a stress-filled life
I noticed signals before I consciously admitted I was stressed
And there were seasons where wearables made things worse:
checking recovery scores like a report card
feeling anxious when a score told me I underperformed or was not recovering
letting a device override my lived experience
In fact, there’s growing concern in clinical literature about wearables contributing to health anxiety in some users. Increased monitoring can increase worry, not reassurance.
Sleep research even coined a term for this: orthosomnia. Patients with objectively normal sleep developed insomnia because they became preoccupied with achieving “perfect” tracker sleep.
I recognized that pattern immediately.
Not because I wasn’t getting sleep in my worst seasons. But I felt very anxious and on edge about my metrics, especially my sleep numbers.
When rest becomes a performance, your nervous system stops feeling safe.
Accuracy isn’t the real issue
People love to argue about accuracy.
Are wrist-based sensors perfect? No. Are they “good enough” most of the time? Probably.
But that’s not the real question.
The real question is this:
What does this data do to your relationship with your body?
Because measurement is neutral. Meaning is not.
Data becomes dangerous when it stops informing and starts judging.
Where I’ve landed now
I still use data. I still think it can teach you.
And I believe the quantified self is a tightrope:
On one side:
awareness
pattern recognition
smarter decisions
On the other:
compulsive checking
anxiety
consumerism dressed up as self-care
The line isn’t intellectual. It’s emotional.
I can feel when I cross it.
My simplest test is this:
If the data makes me more present in my life, it’s helping. If the data makes me suspicious of my life, it’s hurting.
When I catch myself slipping, these are the rules I fall back on:
No immediate morning score-checking
Feel first. Data second.Trends over days
One bad night means nothing. Patterns matter.One variable at a time
Change sleep, caffeine, or training. Not all three.Data doesn’t veto intuition
If I feel good and the score is low, I don’t outsource my agency.Periodic off-ramps
Sometimes the healthiest move is taking the device off.
It’s the same lesson endurance sports taught me years ago:
The goal is adaptation, not domination.
The win isn’t a better HRV or a higher recovery score.
The win is being the kind of person who can use tools without being owned by them.
That’s the athletic part. That’s the aware part. And I’m still learning it.
