A fellow asked, in a Facebook post following my review of the RUNN, “Anyone use this on any of the Curved Manual Treadmills?” Today I’m writing for the 8 people worldwide who’re actually interested in this question (because I said I would), and I thought I’d answer a few other questions, such as, how accurate it this device?

I took the RUNN sensor off my Woodway and placed it on a Trueform Runner, which is a curved, manual (and quite popular) mid-priced treadmill with a segmented belt, like the Woodway. But let’s back up, and I’ll remind folks what the RUNN sensor is and why it's an important device.

A company called North Pole Engineering produced a sensor that you could attach to your treadmill and it would measure the distance traveled and send a Bluetooth signal to (for example) Zwift. This is a big deal, because a lot of treadmills don’t send BLE signals and you can’t run on a platform like Zwift without that signal sent. This sensor became widely available in January (or before, but I became aware of it in January). The folks on our Reader Forum have been discussing it.

So I got one, stuck it on my Woodway, and whammo, great, a BLE signal. I wrote about it. Since that time, a couple of things have happened. One is, North Pole Engineering came out with a firmware update. You’ll find it on the App Store and Google Play, and it’s called Configurez.

Second, I not only tested to see if this device worked on the Trueform, events conspired to cause me to wonder how accurate it is, and how well it comports to Trueform’s own analytics.

The install was easy. I had my issues with the RUNN on the Woodway, and I mean the physical install. Getting the spacing right. I had to jury-rig it a little bit. I wrote about that in my review of the RUNN.

For the purposes of what I'm writing here, I picked the RUNN up off the deck of my Woodway, stuck it on the deck of my Trueform, and stuck 3 stickers that RUNN provides on the belt of the Trueform. (North Pole gives you a spit-ton of these stickers; you won’t run out). I booted up Zwift, it saw the RUNN and that was it. The entire process may have taken me 5 minutes.

Just to make sure there weren’t any dropouts, and that all was honky-dory, I thought I’d make sure that the mileage logged on Zwift (which is the display of the mileage logged on the RUNN) and the mileage traveled on the Trueform treadmill’s own analytics matched. They didn’t. Oops. Which was off?

King Arthur had Excalibur. Brienne of Tarth had Oathkeeper. I have Truthteller. My measuring wheel. I set all devices to zero and commenced. Here is the result. When Zwift says I’ve traveled exactly one mile Truthteller says I’ve traveled 5,260 feet. This means the RUNN device is pretty darned accurate. Almost certainly more accurate than your treadmill. (Treadmills are notoriously inaccurate.) How close is the RUNN to the wheel? At an 8min/mile pace, the RUNN is less than 2 seconds (1.8 seconds) off of what my measuring wheel says.

Meanwhile when my Trueform says I’ve gone a mile, Truthteller says I've traveled 5680 feet. That means that when I’m running an 8-mile mile the treadmill thinks I'm running an 8:36 seconds mile. You can see, below, I’m given the option in Zwift to either pair with the Trueform’s BLE signal, or the RUNN sensor. I'm pairing to the RUNN!

I’ll be writing more about the Trueform mill, because it’s quite a nice mill in a number of ways. Just, if you buy one, and if they give you an option of either spending less money and not having a BLE connection, or paying a premium for a BLE connection, don’t pay the premium! Just pay $99 for a RUNN and you’ll get an accurate measure.

Finally, I have not updated the firmware on my RUNN yet. I took it off one mill, slapped it on another, and did not calibrate it. This is just how accurate these things are.

So, that answers the question about the RUNN on at least this manual, curved treadmill. Works perfectly.

There are other ways to skin this, if you're looking to get a BLE connection into Zwift. One is to just run with a footpod. But there are multiple ways to get a BLE signal from your mill into Zwift.

Make sure your mill doesn't already emit a BLE signal. If it doesn't, before you get a RUNN realize that North Pole Engineering makes another device called a GEM Retro, and it's a slicker add-on, it's internal, goes inside your mill's console, just, your mill has to have what's called a CSAFE port for the Gem Retro to plug into. It's also $99, like the RUNN, and is the cleaner option. However!

You see how treadmills can be inaccurate? If you get your own version of Truthteller, you can see if your mill is delivering accuracy or not, because the built-in BLE, or the Gem Retro, will only take what you see on your console and deliver it to Zwift. You may still be best off with a RUNN, if accuracy as well as connectivity matters to you.