"Whoop" There it is: A Story About Fitness Wearables

The Good, The Bad, and The Kinda Sorta Accurate World of Fitness Wearables

We live in a time when your watch knows more about your life than your mom does. It tells you how long you slept, how hard you worked, and even when it’s time to stand up and stretch. From Garmins to Apple Watches, Oura Rings to Whoops, fitness wearables have become the modern athlete’s favorite accessory. But how much should we actually trust them?

The Good

Let’s start with the fun stuff. These gadgets can be awesome tools for awareness and accountability. They’ll buzz at you when you’ve been sitting too long, cheer you on when you hit your steps, and let you track things like heart rate zones, recovery, and sleep.

For many people, wearables help turn vague goals into real habits. Seeing your heart rate climb during a workout or watching your resting heart rate drop over time can be motivating. They’re like having a coach on your wrist!

The Bad

Fitness wearables don’t actually know you. They’re built on algorithms, averages, and assumptions. That means the data isn’t gospel, it’s more like an educated guess.

If you have ever owned something like this, you may be familiar with this exact scenario. You crush a workout and are active all day, only for your watch to say, “That was an easy day, try pushing harder tomorrow”. Or maybe you’ve woken up feeling great while your ring insists you’re “unrecovered”. These tools can cause you to second-guess your body when you are doing just fine.

About Those Calories…

Ah yes, the watch calorie count. The most loved and misunderstood number in the fitness world.

Here’s the truth: most wearables aren’t great at tracking calorie burn. They use general formulas based on heart rate, weight, and age, but they don’t know your muscle mass, metabolism, or how efficiently you move. Studies show many devices can be off by 20-40%, sometimes more.

So, if your watch says you burned 800 calories during a workout… it might’ve actually been 500. Or 1,000. It’s a ballpark, not a fact.

The (Mostly) Accurate

For the most part, heart-rate data and step counts are fairly reliable, especially for steady movement like running or biking. But once you throw in heavy lifting, rowing, or anything that shakes the sensor, accuracy goes out the window.

Sleep tracking is decent at measuring how long you sleep but not so great at knowing how well you slept. Recovery scores and readiness metrics are interesting, but again, they should support your intuition, not replace it.

The Wrap Up

Instead of obsessing over exact numbers, use those metrics to spot trends. Are you moving more than you did last month? Are your workouts getting more consistent? That’s the stuff that really matters and will move the needle in the long run.

Hart