Do you wonder: Is the Stryd foot sensor worth it? It depends on how und where you run, but let me say this upfront: I wanted to love the Stryd foot sensor. I even bought the newer model to replace my old one and ran over 6,000 km with them over the past four years. But I’ve rarely used the Stryd phone or watch app, and now that my go-to alternative which supported the sensor, iSmoothRun, has been abandoned and good alternative apps for Stryd are hard to find, my time with Stryd is coming to an end.

The Apps are just on piece of the puzzle, there are more problems and chances are, Stryd might not be for you. The idea of training with power instead of heart rate sounds great in theory. But in practice? It’s a mixed bag, and there’s a lot that nobody seems willing to admit about its shortcomings. I want to save you from wasting your money by offering my personal opinion here, but back it up with facts where I find it is needed and possible.

And I also want to safe you some time: If you don’t mind giving up your current running app, and you are an advanced runner with great form, run less than 10-15k mostly on flat streets, and are willing to spend $300—which is painfully close to the price of an Apple Watch—then Stryd might be interesting for you, and you might not need to read this.

What Does the Stryd Foot Sensor Do Well?

  • Absolutely absurdly long battery life.
  • Impressive distance tracking at distances bellow 10k using only an accelerometer.
  • Making the power curve popular.

The bad things about Stryd

Is the Stryd Foot Sensor Accurate for Measuring Power? Only If Conditions Are Perfect

Stryd advertises itself as the gold standard for running power metrics. But the truth is, it’s only really accurate under very specific conditions. If you’re running on flat terrain at a decent speed (say, over 10 km/h), the power numbers are fine. But venture off-road, onto trails, sand, or uneven surfaces? The power readings go completely off. You’d think they’d account for the extra effort needed in those conditions, but no, they don’t.

It’s the same story for hills. The measurements on uphills and downhills are so inconsistent they’re basically useless. I’ve seen this discussed a lot on Reddit, where other users confirm the same thing. Power numbers on inclines just don’t reflect the actual effort, which makes Stryd’s claim of being better than heart rate tracking feel like false advertising. Heart rate might lag a bit, but at least it’s not blatantly wrong.

Don’t take my word for it: Scientific Studies have shown that the Stryd foot sensor underestimates power output, particularly during submaximal running, and fails to account for individual efficiency variations, raising concerns about the accuracy of its power metrics for real-world exertion levels. This study suggests that Stryd’s power calculations are based on a gross mechanical efficiency (GME) of 25%, a value suited for elite runners but approximately half the apparent mechanical efficiency (AME) reported by other researchers. This oversimplification likely causes Stryd to systematically underestimate power output, especially in scenarios where individual efficiency varies, such as hills or uneven terrain. It means to you and me maybe not elite-runners: Stryd is not accurate for us.

What Stryd’s Customer Support Reveals About Their Power Metrics

A support case I had with Stryd made something very clear: They know this. Their power metrics are not measuring your true metabolic effort (power) but are instead based on external physical calculations. As the Stryd representative admitted:

“You are correct. We cannot measure true metabolic effort as you could with a VO2 mask. The uphill power is based on physics, not individual efficiency.”

This means Stryd calculates the power needed to move at a certain pace on an incline but completely ignores how efficient or inefficient you are during that effort. They assume your efficiency is, as per the study linked above if I understand it correctly, is that of elite runners. For inclines, the device can’t account for individual differences, meaning the power readings can be wildly misleading. So if you’re using Stryd to guide your effort or track “time in power zones,” you might not be getting an accurate picture of your actual exertion. Essentially, Stryd’s power readings are only as good as their assumptions, and for anything outside ideal conditions, those assumptions fall apart and makes Stryd not worth it.

Stryds power metrics are off in the real world, which makes HearRate the better indicator all the same

Stryd’s promise is simple: power is supposedly a better measure of training effort than heart rate because heart rate varies with factors like caffeine, health, and time of day. The idea is to use physics to bypass that variability. But here’s the catch: it only works if power is measured accurately—and it’s not.

Think about when you care most about effort metrics. Is it on flat terrain? No, it’s during pace changes caused by hills or uneven terrain. Ironically, that’s exactly when Stryd’s metrics fail, making heart rate the more reliable guide within a run. Admittedly, between two runs (as factors like health and caffeine can play a role), even the poor measurement from Stryd may be the better indicator for comparison, but that really only works under perfect conditions.

As someone who runs trails and hilly routes, I gave up on looking at Stryd’s power data during runs years ago. Heart rate not only makes more sense—it feels like the better guide. For a while, I stuck to look at the power curve in the StrydPowercenter, but my Apple Watch combined with HealthFit or Runalyze handles that just as well. With most of Stryd Powercenter’s advanced stats locked behind a paywall, all that’s left is distance tracking, which became irrelevant once I started running longer distances (20k+). For longer distances Stryd is not worth it. See next paragraph.

Is the Stryd Foot Sensor Reliable for Distance Tracking?

For short distances (up to around 10-15 kilometers), Stryd’s distance tracking is pretty spot-on for many runners. But if you’re training for a marathon or ultramarathon, don’t trust it. Over longer distances, the measurements start to drift. For a device relying solely on an accelerometer, such inaccuracies are to be expected. What’s surprising is that Stryd doesn’t allow runners to validate, cross-check, or correct these measurements using GPS data, which is already being gathered by most apps and even Stryd itself. Instead, they insist on sticking exclusively to the accelerometer, ignoring the potential for improvement. A lot of people don’t talk about it, but it’s something I’ve seen echoed online too.

Don’t get me wrong, I have to hand it to Stryd: measuring distance even “just” that precisely using only acceleration is genuinely impressive. That they can be off by multiple kilometers in a marathon isn’t surprising, it’s to be expected. My real issue with Stryd is their lack of honesty—about this limitation, their unwillingness to implement obvious solutions for the distance problem, and more importantly, about the shortcomings of their power measurements.

Does the Stryd Foot Sensor Accurately Measure Wind Power? Gimmick or Game-Changer?

One of Stryd’s big selling points is its ability to measure wind resistance. It sounds like a cool feature, right? But in reality, it’s more of a half-baked gimmick. It captures some of the extra resistance from wind, but it’s not enough to make a meaningful difference in most situations. Honestly, it feels like a checkbox feature they added to stand out, rather than something that actually adds value. As power readings are off anyways this just doesn’t play any role and doesn’t make the Stryd foot sensor worth it.

The Software Ecosystem

Here’s where my frustrations really start to pile up. In my opinion Stryd’s app and platform are just not very good. The Apple Watch interface is subpar. On top of that, they’ve locked most of the analytics behind a subscription paywall making Stryd not worth it. I use Runalyze, which is free and way more powerful, but Stryd doesn’t make it easy to export your data there. You either have to move files manually or use a workaround like HealthFit which in turn loses some of the recorded data during the transfer. Why make it so hard for users?

The worst part? Stryd actively discourages third-party integration. For example, the developer of WorkOutDoors, an excellent Apple Watch app, shared with me how Stryd doesn’t share their data format, making it impossible to capture all metrics and another developer shared on reddit the same experience forcing him to reverse engineer Stryds protocol. Stryd’s attitude here is disappointing —it looks like they’re trying to lock users into their ecosystem, even if it means alienating those of us who prefer better apps.

Reddit Post Locking: A personal anecdote.

Stryd’s gatekeeping extends to their own community. As it became evident In a recent Reddit post where I was asking for alternative Apple Watch apps to use with Stryd. Instead of fostering open discussion, the mods—who seem connected to Stryd—locked the thread, citing what they considered a false statement I made about them removing features for existing users. They explained this as a “pioneer program” being phased out or something, which could be seen as a matter of interpretation. But, let’s give them the benefit of the doubt and say it didn’t happen the way I experienced it. I may have misunderstood something, all I know is the features were gone for me. Still, it’s a minor detail compared to my broader concerns which made up the majority of the thread on reddit. When I pointed this out in a follow-up post, they deleted the post and chose to ban me from the subreddit. That speaks volumes about their general attitude—they don’t want open criticism, and mute critical voices.

If you’re wondering whether a product is worth your investment, look at how the company handles criticism. Do they acknowledge shortcomings and work to improve? Or do they dismiss concerns, mute criticism (like locking discussions or banning users), and double down on their faults? If it’s the latter, I steer clear.

Does the Stryd Foot Sensor Live Up to Its Marketing Hype?

Stryd’s marketing feels off to me. Their ebooks are so over-the-top positive, claiming Stryd is the ultimate solution to all your running problems, that it’s hard to take seriously. When you know the device’s flaws, the bordering on snake-oil tone becomes hard to stomach for me.

Final Verdict: Is the Stryd Foot Sensor Worth It?

Here’s my take: Stryd’s hardware has potential, but it is hindered by its limitations and the company’s lack of transparency and honesty in marketing about those limitations. Therefore in my opinion Stryd is not worth it for most runners given the limitations, features, price, paywall structure and general attitude of the company.

If you don’t mind giving up your current running app, you are an advanced runner with great form, run less than 10-15k mostly on flat streets, and are willing to spend $300 then Stryd might be interesting for you though.

But if any of those things don’t apply, Stryd is not worth it for you, in my opinion. For trail runners, hill lovers, slower paces, or anyone who values flexibility with software, Stryd will leave you frustrated. For just 100$ more, you can get an Apple Watch—it now also tracks power, is one of the best heart rate monitors available, and offers far more versatility. Bundled with other free apps you get the power curve too.

Is the Apple Watch an Alternative for Stryd?

In my preliminary tests, Apple Watch’s power measurements also seem “off,” but likely in a different way. That said, Apple has the resources to pour millions into developing and refining, meaning it will only get better over time and Apple can use far far more powerful computing power in the watch. Stryd, with its smaller company scale, dismissive attitude toward critique and in-foot-pod computation, simply can’t keep up.

I think measuring running power accurately is a challenging task, and I’m quite impressed by how close Stryd gets using just a foot sensor to provide real-time power output. Even if I criticize the company here openly and perhaps harshly, I have a LOT of respect for the engineers at Stryd who have brought the product this far. However, I also believe this technological approach is precisely why Stryd falls short when it comes to accuracy in different scenarios and different runner-efficiencies. In my view, power measurement cannot be fully resolved through mathematical methods, as I believe they are using in the pod, alone. If running power is ever going to be accurately measured in all scenarios, it will require the use of machine learning or artificial intelligence. Similar to what the Apple Watch probably already employs and continues to enhance.

For me, this is my last Stryd device and I don’t recommend buying one.