TreadTracker Treadmill In-Depth Review (And a Treadmill Accuracy Rabbit Hole)

We’re starting off the New Year with something from the old year. I bought the TreadTracker a year ago, and I’m finally getting around to posting about it. Fear not, what’s old is new again. And, for many of you mid-winter, what’s old is still very relevant (since there’s nothing else like it).

The TreadTracker is essentially a Bluetooth Smart footpod that doesn’t require a foot. Instead, it sits below your treadmill and has a smaller roller wheel that tracks your treadmill’s pace and transmits it as a Bluetooth Smart footpod sensor that any app (like Zwift) can pick up and utilize. The main reason to use something like this is that it’s ‘set it and forget it’, or if you have multiple people using a treadmill. Whereas a footpod is certainly more portable (such as while travelling), but some may require calibration and frequent charging. Plus there’s the question of accuracy. But fear not, we’ll get to that.

Oh will we ever! I’ve spent probably 8+ hours today alone on looking into accuracy, and in particular, accuracy of my treadmill and other methods to validate that. It’s now 1:30AM though, and I’ve satisfied the itch that I stumbled upon this morning. So come along on that journey.

Now if you’d like this entire review in one nifty video – then go no further than the play button below:

Else, onwards with the photos and text and plenty of data!

What’s in the box:

The box is pretty straightforward, which I like. Here’s the outside:

Inside, you’ve got the unit protected by some plastic. Take it out and you’ve got the unit, some paper stuffs, and a mini-USB cable for power/charging. Oddly however, you don’t have a USB to power outlet adapter. Given this is something that’s somewhat designed to be plugged in permanently, it seems like a quirky oversight. No worries, I have plenty.

Here’s the manual. It’s pretty straightforward, we’ll talk more about how to use it in a second.

And that’s all there is in the box. Not much more to say here. Let’s get into using it.

The Basics:

This device is silly simple to use, so I’m going to try and keep this efficient. I’ll still probably fail at doing so.

The TreadTracker is designed to be placed below your treadmill such that it snuggles up against the belt, measuring the speed of the belt using the small roller wheel at the top of the TreadTracker.

However, a key part of that snuggling bit is ensuring it can adapt to different treadmill heights, and ensuring that it keeps a tight fit to the belt while doing so. So the entire unit comes ‘locked’ by default, which means that it’s lying flat like this:

However, on the bottom there’s a little lock latch. Once you unlock it, the unit pops up:

It’s on a spring, so if it ‘hits’ your treadmill belt before it reaches its peak – then that’s all fine. If however after the first un-popping it’s still not long enough you can extend it again:

The minimum clearance you need under your treadmill is 7cm, and the max it can handle is 21cm.  Here it is sitting under my treadmill:

On the face of it there’s two lights:

Blue Light: Bluetooth Smart Status light
Other Light: Battery indicator

That battery indicator has three status levels within it:

Green: Battery above 50%
Orange: Battery less than 50%
Red: Battery less than 10%

The unit should be charged with a 1AMP USB plug (most plugs will be close enough to cover this, or slow charge it at worst).


Meanwhile, on the bottom there’s the lock for the arm:

However, there’s also a small plate that extends out and allows the unit to rotate slightly and pivot. This is actually kinda cool and is notable in case there’s any unevenness.

When it comes to placement of the unit, the company recommends the center of the treadmill in their manual:

However, online in their FAQ section it says it doesn’t matter, as long as it makes contact with the belt.  I tried both positions and tested accuracy for both and found no difference.  So for me, I prefer the back because then I can easily see/check the status lights if need be.

Note that you do NOT need to use the RunSocial app at all – ever. Not once. However, if you do download the app, you can actually customize the broadcasted Bluetooth Smart name. This would be useful if you had multiple units and wanted to name them (e.g. ‘Treadmill 1’, ‘Treadmill 2’, etc…)


Most of you will be using TreadTracker with Zwift running (or some other indoor app, I suppose).  To get it configured there you’ll simply open up the run pairing screen and then select the TreadTracker from the list:

And…you’re done.

Seriously, it’s that easy.

Note that Zwift will automatically pair to the cadence channel from the TreadTracker, but in reality the TreadTracker doesn’t transmit cadence (it’s just part of the BLE footpod spec, so TreadTracker conforms to it). Thus, if you have some other thing that’ll transmit running cadence, you’ll want to select that for cadence.

Simply pair to your HR strap if you have one and you’re off and running (literally):

Your pace will be displayed automatically in the app, based on the speed of the belt of your treadmill. In an ideal world, that’d match the actual speed on the treadmill, but that’s an entirely different ball of wax that I’ll cover in the next section.

Reaction time is virtually instant in my experience – super quick. In fact, you can see it’s a slight bit faster than Stryd is, if you overlay the two charts together. Here it is against the treadmill as well. Now, the accuracy isn’t good on this treadmill as I discovered, but you can see at least how quickly it responds in the intervals:

Zwift aside, what’s cool here is that it’s a standard Bluetooth Smart footpod. So it’ll work (in theory) with any Bluetooth Smart footpod capable device. For example, I successfully paired it up to my Garmin Fenix 5 Plus to get pace/distance into that, while that was attached to the treadmill:

Sure, I could have worn the watch and got a rough approximation, but that doesn’t often handle things like dorking with treadmill speed or drinking from a bottle (or wiping sweat) very well.

While I haven’t tested it with other devices/apps, it should also work with both Polar and Suunto watches as well.

In any case, the key message here is that it ‘just works’. There’s almost nothing to do except run on your treadmill and have it transmit pace and thus distance. Again, no cadence however.

Accuracy Testing:

It’s funny, accuracy testing this device should be easy. But in reality, it’s anything but. There’s a surprising number of ways things can differ, and more importantly – a hilarious number of ways it can go horribly wrong.  I’ve taken the assumption that my treadmill may not be accurate. That’s usually a good assumption to make. If you’ve done any amount of treadmill running at gyms and hotels you likely know how different they can be. Even two identical treadmills side by side in a gym are somehow significantly different in pace (and thus distance).

My treadmill is about 3-4 years old, though it doesn’t actually have a ton of mileage on it. Almost all of my running is outdoors, and so my guess is that this treadmill only has about 80 miles on it. Not much (which usually drives the accuracy side of the equation). Before doing these tests, I calibrated the treadmill per the manufacturer’s instructions.

So, I set about trying to validate it, and thus by extension the TreadTracker.

Do to that I’ve got three validation sources. I’m not necessarily claiming that any of these devices is a known ‘good’, but, it’s just four devices to work from.

1) Orange Measuring Wheel (This one): This is specifically designed for measuring courses (orange one)
2) Yellow Distance Tracker: This isn’t so much designed for measuring running courses, but just distance (yellow one)
3) TreadTracker: The thing this entire post is on
4) ProForm 1250 Treadmill: My crappy treadmill

Invariably someone will say ‘Get a Jones Counter bike!’, and sure, that’d be nice. But that also presents the slight challenge of putting it on a treadmill.  I could also leverage other magnet-based sensors as well to measure and place that bike on the treadmill somehow. But I think I’ve got enough sources.

Of course, then there’s the mother of all sources: Math

Ironically, the subject I hated the most in school. And no, I still haven’t had any use for calculus in my life yet.

In order to math this out I had to do some measuring on my treadmill and paint out some lines. I started off with a ‘0’ (zero) marker and then painted a line every 1 meter.

I had no idea how long the belt would be, but turns out my arts and crafts project was short-lived. The belt was exactly three meters long. So I had a ‘0’, ‘1’, and ‘2’ lines. I then put another line on the other side of the treadmill at the ‘0’ marker so I could easily see it and count it.

Then, I simply turned on the treadmill to a lowish speed, 3KPH, so I wouldn’t miss any lines as they went by, and then counted them. I used a random free counter app off the app store:


Because I got bored of counting lines quickly, I decided to simply go for 34 lines. I was going to do 33 rotations, but then I couldn’t get it stopped fast enough, so 34 it was. Or 102 meters worth (each rotation is three meters). While my orange and yellow counters measure in feet/inches, I converted them to meters to keep things sane here. When the marker line went past the marked starting point, I measured the ‘extra’ distance and added it in. And thus, the results:

Math Distance: 102.3 meters (true distance)
TreadTracker via Zwift: 100.0 meters*
Orange Counter: 101.83 meters
Treadmill: 111 meters

Now, there was a slight problem there. Zwift only shows me the distance in increments of 1/10th of a kilometer. For example. .11 kilometers, .12 kilometers, etc… Meaning a gap 10 meters. Too high for what I wanted.

So I found a Garmin Connect IQ app for my watch that would show me straight meters (up to 1-kilometer), so it would show me exactly 101 meters, etc… Perfect. I paired the Fenix 5 Plus up to the TreadTracker as a Bluetooth Smart footpod and then did the test again:

Math Distance: 102.9 meters (true distance)
TreadTracker via watch: 100.0 meters
Orange Counter:
103.0 meters
106 meters

Ok, getting closer.

Now before that, I had done some 1KM in length tests. Except at this point it’d take a lot of waiting and likely screwed up counting to get the marks counted. So instead I went with just these three sources. Here’s round #1 where I slowed to a crawl and then stopped the treadmill at precisely the moment Zwift showed 1.00KM.

TreadTracker via Zwift: 1000 meters
Orange Counter: 1027.4 meters
Treadmill: 1057 meters

And, for fun, I did it again. Both of these tests were done at 10KPH (to reduce chances of belt slippage on the counters which I found starts to happen above those speeds):

TreadTracker via Zwift: 1000 meters
Orange Counter: 1029.8 meters
Yellow Counter: 1024.9 meters
Treadmill: 1056 meters

Ok, so at this point I’d summarize things as follows:

1) The treadmill is definitely off, by roughly 2.5% to 5%, usually reading faster than it is
2) The two roller counters are really darn close to each other
3) The TreadTracker is very close when using Zwift to record (within 1.0-2.0% total distance)
4) The TreadTracker is even closer (within 2.5% matching the counters when using the Garmin watch to record)

So why the slight variance between using a Garmin and Zwift? I suspect it has to do with either dumb luck, or some aspect of how precisely Zwift counts, especially when the unit first starts and stops. Keep in mind we’re talking distance here that are relatively small (1KM tests).

Thus, let’s increase the distance. This time I went with a longer run, a structured workout on Zwift with paces all the way up to 15.6KPH. It looks like this:

Now, there was one failure during this test. After the very last interval during the cool-down Zwift and TreadTracker randomly stopped talking. Zero pace displayed. I ended up rebooting the TreadTracker and that solved it. I haven’t ever seen this before. So there was about 10-20 seconds (at 10KPH) that I was trying to figure out what the heck was going on, and thus the Zwift/TreadTracker and Stryd total would be reduced by 10-20 seconds worth by the time I got everything stopped. Nonetheless, here’s those totals for the fun of it:

Stryd: 7.91KM
TreadTracker: 7.92KM
ProForm: 8.36KM

Here however are the totals if I snip to the point prior to the dropout:

Stryd: 7125.87m
TreadTracker: 7172.31m
ProForm: 7319.29

Here’s how that looks from a pace overlay standpoint in the DCR Analyzer:

And here’s how that looks if I plot distance over time.

Interestingly, one thing I clearly noticed in my faster intervals (thus above about 14.5KPH/9MPH which is 4:10/KM or 6:40/mi), is that the treadmill actually surges faster even though the speed on the treadmill remains the same. I can audibly hear the motor surging, my legs surging, and then the TreadTracker and Stryd footpods surging. Meanwhile, the treadmill itself does the equivalent of ripping a silent but deadly fart in the middle of a packed conference room, without admitting it. It plots the same pace, even though it surges from 14.5KPH up to about 15.1KPH (3:58/KM or 6:23/mi):

So what’s my total accuracy round-up here? I like bulleted lists, they’re simple:

A) My treadmill isn’t super awesome (which, I already knew in general, but this confirms it)
B) The counter wheels bungee corded to my treadmill are surprisingly good at accuracy
C) The TreadTracker is within 1-2% in most cases of math, and seems to respond very quickly to pace changes

I’m looking forward to trying this with the rebranded $29 Zwift (Milestone) Running Pod when I grab it next week. I have an earlier Milestone pod I’ve long used, but I figured I’ll test out the newly rebranded version. I’ve got one I ordered that should show up next week.

Side note: No, I don’t plan on making a habit of reviewing treadmills (and this would not be a review of my treadmill, though I’ve noted many times I dislike it). I might do others if there’s some unique to market treadmill that shows great interest from readers. But for the most part, I don’t terribly enjoy running on treadmills, so it’s gotta be something that’s totally different and thus appealing in some new way.

Another note: All of the charts in these accuracy portions were created using the DCR Analyzer tool.  It allows you to compare power meters/trainers, heart rate, cadence, speed/pace, GPS tracks and plenty more. You can use it as well for your own gadget comparisons, more details here.


In some ways the best question about this is actually more like who’s it for?

For many people, it might be easier to just pick up a footpod and have it always on their shoe. That way if they’re out traveling the world, it’ll give them mostly accurate pace/distance no matter what treadmill they’re on. Certainly a coin-sized footpod is easier to travel with than this nearly shoe sized device.

But footpods aren’t quite as stable as some people think they are. They’re often prone to slight tweaks in pace based on shifts in cadence or even running style/efficiency. Sure, those like Stryd are quite good – but they’re not perfect. Same goes for the Milestone/Zwift pod. Of course, Stryd is $199, and the Zwift pod a mere $29. Obviously Stryd’s pod does power and other things, but most people don’t care about that.

The appeal of the TreadTracker is that it’s set it and forget it, especially for those with more than one person using it. For example, The Girl and I using the treadmill. In this case it just sits there below the treadmill and available for use for whoever jumps on – zero calibration needed. Heck, the name even looks like it’s the treadmill.

Will it make sense for everyone? No, of course not. But I actually like the idea. I’m very much a ‘set it and forget it’ kind of person. I want to jump on and not worry about whether or not my footpod is properly calibrated (or charged). It has a high ‘just works’ factor.

With that – thanks for reading!

DC Rainmaker :

View Comments (99)

  • I have done Similar to Calibrate my Garmin foot pod for when I am forced to use treadmill because of inclement weather. (My tests were at much slower pace.) I used a small magnet siliconed to belt, measured belt length, Hall effect sensor module and an Arduino pro-mini microprocessor communicating by serial connection to my computer. This is very accurate (more so that what treadmill says). I used the distance from my measurements to arrive at Calibration Factors as follows:
    Treadmill Jog CF 110.3
    Treadmill Walk CF 95.7
    Treadmill Interval (Ranging between 5.7 to 7.5 KPH) CF 107.3
    1. A second Garmin footpod and a Myfit pod [Milestone] gave similar results.
    2. I do not let my Garmin Foot pod auto calibrate.

    • Thanks Jonathan! Looking forward to seeing more of the build writeup. Any chance you can post your Python code to your github site from your raspberry pi proof of concept too?

      Still fighting some memory issues on my 8266 "auto treadmill" but hopefully can write something up soon!

    • That's an interesting idea. While I was waiting for the NRF board to show up I was doing some testing with an Arduino an the GY-521 accelerometer/gyro dev board to see if I could I identify foot strikes through vibrations in the treadmill with the setup roughly where I planned on putting the optical sensor. The foot strikes did stand out versus the general noise/vibration that the treadmill produced, so I think it could be done.

      I was kind of hoping to get the best of both worlds. Have my "foot pod" sensor report distance/pace and have the watch fall back to its internal accelerometer for cadence tracking. In the capabilities page of the SDM ANT+ data I report that cadence is not valid but the watch (Garmin Vivoactive 3 Music) never requests the capabilities page and it also doesn't appear to use its own accelerometer (at least for the recorded activity) if a foot pod is present. Interesting enough, it does seem to still be internally counting footsteps as I've gotten the goal message during an activity.

    • How about adding a microphone sensor and using the spike in noise passing a certain threshold from each foot-strike to get cadence?

    • I'm definitely planning a full write-up of all of this and I'll share the code and as much of the compiled binary as the ANT+ agreement lets me. I'm still tweaking the code to work through some slight oddities I'm seeing while masquerading under the ANT+ SDM (foot pod) spec since I don't really know the cadence or strides. Last Sunday was my first long run with it on the treadmill and it's just about there.

      The very short version is that it uses an NRF52840 dongle (around $10 US) and a variable distance optical obstacle detection board (about $1 US) to trigger an interrupt every time a white mark on the belt is seen. I put one paint mark on the belt (originally started as tape but they got spit off every time at various distances). I measured the belt similar to how Ray mentioned above. Knowing the belt length, each time mark is seen I increment the distance by the belt length and recalculate pace using time elapsed between the last seen mark and the current mark. The code started with porting the SDM Tx example in the Nordic SDK to the NRF52840 dongle and it uses the S212 SoftDevice for ANT+.

    • Yes! Please write this up!

      I've been all over the Internet looking for an old nrf24ap to try and get ant+ working with an esp8266 or esp32, but I saw they have some nrf52840 development boards now that can run micropython, which I've been using to get an ultrasonic distance sensor working to automatically adjust my treadmill speed based on my position on the belt (start running faster and farther forward speeds up and vice versa). Hoping to document my process as I finish up. All of the wiring/soldering on my treadmill is completed, and this afternoon I got the software and relays (start/stop/faster/slower/incline up/down) completed but there will be tuning and other issues when I get on the treadmill.

      After speed is working, my plan is to adjust grade based on in-game Zwift grade using the zwift-client Python library. Would love to hook relays up to my cheap $15 three-tiered fan and adjust speed based on hr/power or "cave" temperature/humidity either through ant+ or the values from the zwift-client,to create a poor man's Wahoo Wind...

    • Great idea. Since my response #64 I now send arduino serial data for distance straight to an excell spreadsheet every second with PLX-DAQ. I have trialed both the Garmin and Milestone (Badged as MyFit here in Australia) POD's and confirmed the Milestone follows My measured treadmill pace more reliably. (Attached graph). My next step was to get this onto my Garmin Fenix 3 HR. You have already done this. Would appreciate your build and coding details. Ray might approve of us communicating direct by email. I will ask him.

    • I went with an optical sensor, white paint mark, and an NRF52840 dongle to build a treadmill "footpod" to broadcast distance and pace right to the watch via ANT+.

      Saw similar results to what others described. Unloaded, the treadmill belt moved considerably faster than the displayed speed. Loaded, the belt speed was closer to the display, but still faster.

      Either way, the reported distance and pace is now much closer to what the treadmill says than what the watch's internal accelerometer comes up with.

    • ok this is kind of cool in a completely geeky way. I find that on the TM my garmin foot bod think I am running 45 Sec FASTER per mile... it is great when my coach thinks I just did 10 miles at a 6:30 pace but it isn't real... and the calibrate function of the Fenix doesn't go down in miles... I guess it assumes only up

  • The bullet no 4 under “Ok, so at this point I’d summarize things as follows:” - that the TreadTracker with watch to record is within 0.5 % - does not fully align with the results, unless the 100.0 m for TreadTracker in the second 100m-test (using Garmin watch) should say something other than 100.0 m. (It may also be the case that I misunderstand, but I’ve read that section several times now)

    • Yeah, somehow on that 4th bullet I started a thought and then apparently finished with another one. Fixed it.

  • I'm already looking forward to finding one of these waiting for me under a gym treadmill. Wait, I meant under a Christmas tree. Yeah, Christmas tree.

  • I'm looking forward to your test of the Zwift RunPod since I've not been able to get mine to work. Part of it may be that I'm not really running. I mostly walk in the 3-5 mph range as a cool down after I ride. The RunPod just doesn't want to calibrate at these lower speeds and even if I manage to get it to calibrate at higher speeds it's wildly out of wack with my Landice treadmill and will not show any movement in Zwift until I pick up the pace.

    By contrast, all works just fine with my Wahoo TICKR X. Speeds are much closer and Zwift actually shows some movement even when I'm not moving. That's not right either but it is better than the alternative.

  • “Obviously Stryd’s pod does power and other things, but most people don’t care about that.” — yes, in the same way cyclists don’t care about power 🤔

    Stryd doesn’t “bounce around” in terms of pace, as your own testing above shows. In fact the take-away from this article seems to be how accurate Stryd is.

    • I'm saying similar above - why buy stryd for power, when you can buy runscribe for dual sided power and dual sided gait metrics?
      I honestly don't understand stryd's thinking and they risk being made redundant at that price.

    • I’m referring to the larger population of runners, which overwhelmingly don’t care about running power.

      I’ve argued repeatedly that Stryd is essentially slow-blowing any advantage they have adoption wise by keeping prices so high. It’s only a matter of time before everyone follows Polar and running power becomes commodity.

  • I run on one of those fancy Woodway treadmills. Any idea how the TreadTracker works on Woodways or other treadmills that use slats instead of a smooth belt as a running surface?

  • Many thanks for an interesting article - I use a footpod with Zwift on a number of treadmills at a couple of gyms and have been interested in trying to get a more accurate speed/distance as I can see the limitations of both pod and treadmill. I seem to have come to a separate conclusion to the article based on the same results you have provided and want to, please, check I have understood them correctly?
    - In most of the results it appears the math distance and the Orange counter are near identical (this does not surprise me given those type of Orange counters are usually calibrated at the factory and the tyre on the wheel probably hasn't worn down much since then). Given that, I'll take either of those two measurements are "base" case.
    - If I then take the variation of the TreadTracker from that "base", it is not that much better than your treadmill. The Tread Tracker on the 1000m tests was around 25m less than "base" and the Treadmill around 30m more than "base". Other distances seems to show similar % variations with the Tread tracker 2.5% lower and the treadmill 3% higher.
    - You describe your treadmill as not very good.

    Given the TreadTracker is only about as accurate (okay maybe 0.5% better) than a not very good treadmill, why would I spend $200 on it? I may as well take speed/distance of the treadmill given its roughly the same level of inaccuracy?
    At $200 I would have expected the TreadTracker to have been at least as accurate in distance terms as the Orange Counter, unless I have misunderstood the results? Given that it deviates away suggests it either (i) doesn't maintain as a good contact/tracking of the belt as the orange counter Or (ii) isn't properly calibrated Or (iii) has a software issue reporting the right distance to the recording devices.

    • One other thought on the accuracy of the TreadTracker...given its fairly small wheel, any deviation from being exactly 100% parallel with the belt would give an inaccurate result? ...and notably it would be less than true distance recorded.

  • Another potential source of speed/distance measurement is to strap your bike (or just a front fork) to it with a regular ANT+ speed sensor! As long as you measure the wheel's circumference accurately you should get good figures.

    • No worries David. I confirm the methodology workes well. Allowed me to use the lower priced Footpod with an accurate calibration factor for treadmill walking/Jogging. It is my experience that these units have very limited capacity to cope with changing Gaits at slow paces. This is easily observed by viewing real time Footpod pace with different gaits and constant treadmill speed. This is what first alerted me to the issue.

    • My apologies to David Warren - he was clearly ahead of me with the magnet thought and took it much further.

    • But I'd think that adding an optical or magnetic pickup on the mat would be more accurate and subject to a lower failure rate than a mechanical contact wheel.

    • My guess would be that a properly placed belt magnet might be a better 'known good', whereas a treadmill may be placing a magnet/sensor on another upstream piece (such as a motor that has a smaller circumference) that could be out of alignment (or definitely is, as seen here).

    • How is this any better than the optical/magnetic sensor that is built in to the treadmill?

    • Or how about fixing a magnet to the belt and using an old fashioned magnet activate speed sensor?

  • Hi Ray !
    I bought a treadtracker last year, it lasted a couple of time before not charging. I had a chat with customer service and they sent me a brand new one without asking the old one back.
    I received the second one, used it twice and then the same thing, the unit was not charging. I contacted them again and they reinbused me since they didn't have any to send me back at the moment. The customer service is incredible ! The product ... well I'm a bit dissapointed.

    While I was using it I found it perfect ! Speed was spot on. Only drawback is that since it's bluetooth, I can't send the data to my garmin 935 and my computer with Zwift, I have to choose.

    Someone had the same problems or am I the only one ?

    • Nope.. looks like Bluetooth only and therefore only one client. You would need something to bridge the bluetooth to Ant+

    • Hi snowfree52!
      Did I understand correctly that it is not possible to pair the TreadTracker in parallel with the Garmin 935 and Zwift?
      Basically, it would be possible with Bluetooth.

  • I use a milestone pod and am wondering how the zwift run calibration interacts with the pod calibration? i.e. there's a milestone app that calibrates the pod. If you then do the zwift calibration, which one is being used?

    • I have comfirmed with milestone that their calibration from their App is loaded onto Pod. To reset pod without calibratation take out Battery and reinsert. Do not sync with their app. I have also confirmed with Wahoo that their calibration factor only works within their app. I do not know for zwift as I do not use that App.

    • I believe the calibration is loaded on to the pod. So the most recent calibration is the one being used regardless of the app used. But I could be wrong. :-)

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