Experts often have strong opinions about the methods they love. And why wouldn’t they? They’ve seen those methods work time and time again. Their experience gives them confidence—and it should.
But there’s a problem we don’t always see. The same experience that builds confidence can also create blind spots. It’s easy to assume that what worked for one person—or even many people—must work for everyone. And it’s just as easy to assume that something we’ve seen fail won’t work at all.
That’s where confirmation bias sneaks in. It’s the tendency to notice what supports our beliefs while ignoring what doesn’t.
The Heavy Lifter’s Bias
In the fitness world, there’s a corner of the industry that champions heavy resistance training. Trainers in this space swear by progressive overload and argue that heavy lifting is the gold standard for recovery and strength. On the other side, there’s a camp that advocates for stretching, low-load exercises, or even passive interventions. Both sides are passionate about their methods, and both have seen results.
But here’s where the bias comes in: each corner tends to see the cases where the other side didn’t work.
Trainers who emphasize heavy resistance training often encounter clients who have already tried stretching or light exercises without success. These clients arrive frustrated, looking for something more effective. Heavy lifting is introduced, and progress follows. From the trainer’s perspective, it seems clear: heavy resistance training works, while stretching or light exercises don’t.
Meanwhile, trainers who focus on stretching or low-load interventions see the opposite. Their clients come to them after trying heavy lifting and feeling worse—overloaded, burnt out, or even injured. These trainers implement their preferred methods, and their clients improve. To them, it’s equally obvious: stretching and light exercises work, while heavy resistance doesn’t.
The truth? Both sides are shaped by the cases they see, not the ones they don’t.
The Blind Spot
Neither camp sees the full picture. The heavy lifters don’t see the people who recovered with stretching because those people never needed heavy lifting. The light-load advocates don’t see the successes of heavy lifting because those clients never needed stretching. Each side’s clinical experience becomes a spotlight, illuminating only part of the field while leaving the rest in shadow.
It’s like two cooks arguing over the best recipe. One always uses butter, and the other swears by olive oil. Each has happy diners singing their praises, but neither sees the meals that succeed with the other ingredient.
This divide isn’t just about preference—it’s about perspective. Confirmation bias grows when we assume that our spotlight shows the whole story.
The Two Coffee Shops
Imagine two coffee shops in your neighborhood. You love one of them. The coffee is perfect, the baristas are friendly, and the atmosphere is cozy. You’ve had so many great experiences there that you can’t imagine the other place being any good.
But what if someone else feels the same way about the other coffee shop? They’ve never tried yours because they’re so happy with theirs. You both have solid reasons for your opinions, but you’re each missing the chance to see the other side.
It’s not that either of you is wrong. It’s just that your experience has shaped what you believe to be true.
When Different Approaches Work
Now let’s bring this idea into everyday life. Say you and a friend both have trouble staying organized. You swear by writing everything down in a planner. Your friend uses their phone for reminders. Both methods work—for you. But because you’ve never tried your friend’s approach, you assume it wouldn’t work for you—or anyone else.
Your friend feels the same way about your planner. They think it would just gather dust.
The truth? Both approaches can work. But confirmation bias makes it easy to think that the other way won’t.
A Balanced Approach
This is why humility is so important in the fitness world—and in life. Both heavy lifting and stretching have their place. They serve different needs for different people at different times. The challenge is stepping back to recognize that no single method works for everyone.
When the industry divides into camps, it risks turning fitness into a zero-sum game. Instead of learning from each other, we dig in deeper, defending our corner and dismissing the rest. But real progress comes from listening, observing, and acknowledging that there’s more than one path to success.
What Can We Learn?
For trainers, fitness enthusiasts, and everyone else, this divide offers an opportunity for reflection:
- Where do your biases come from? Are your opinions shaped by the successes you’ve seen—or the failures of another method?
- Have you dismissed an approach without fully understanding it? Could the method you’ve avoided have value for someone else—or even for you? I wonder who this would work for?
- How can you embrace a broader view? What would happen if you learned from the other corner instead of arguing against it?
A Little More Humility
Bias is part of being human. But when we recognize it, we can work to overcome it.
The fitness industry doesn’t need more factions. It needs more collaboration. Because when we step out of our corners, we see the full picture—and everyone benefits.
Whether it’s heavy lifting, stretching, or something entirely different, the answer isn’t in proving one side right and the other wrong. It’s in learning from both.
When we remember that our experience is only part of the story, we open ourselves up to learning, growing, and understanding others better.
Because sometimes, the best coffee shop—or the best solution—might be the one we haven’t tried yet..