The McNamara Fallacy

"What does not get counted does not count." – The McNamara fallacy.

Recently, an athlete came into the store and mentioned he'd run a marathon. He said it was a "bad day" because his training data indicated he should have run much faster.

I love data. I love the tools that collect it—power meters, heart rate monitors, GPS devices, Oura rings, TrainingPeaks, and the list goes on. Data can be invaluable and often offers great insights. But when we rely on data, we must also be aware of the four steps that lead to committing the McNamara Fallacy:

1. Measure whatever can be easily measured. (Thank you, power meters, heart rate monitors, GPS devices, and TrainingPeaks!)
2. Disregard what cannot be easily measured. (I’m under a lot of personal stress right now...)
3. Presume that what can’t be easily measured isn’t important. (It’s hard to quantify and measure personal stress...)
4. Conclude that what can’t be easily measured doesn’t exist. (Goodbye, personal stress!)

I make a living selling tools that offer insight into fitness and training, and I fully believe they belong in any serious athlete’s arsenal. However, we need to recognize that we often give extra weight to the "hard" data we can collect easily, while we overlook the "soft" data that's difficult to quantify.

"Hard" data, like miles per week, average pace, power, heart rate, or training stress score, are useful but lagging indicators. We rely on them because they’re easy to measure with modern tools.

On the other hand, "soft" data—things like personal stress, morning freshness, and excitement levels—are harder, if not impossible, to measure. Yet these often serve as leading indicators of how a workout or race will unfold.

It’s worth remembering that not long ago, athletes didn’t have access to the incredible tools we have today. What did athletes and coaches rely on back then? Often, just a stopwatch—if that. And, in truth, that’s still not a bad tool. For those of us who are competitive, it’s important to recognize that we don’t race for power, cadence, or heart rate. At the finish line, there’s only one tool that matters: the clock. We race for time, and many athletes would do well to keep that in mind.

Antonio Gonzalez

Tri Town Bicycles

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