The Runn Smart Treadmill Sensor is a clever device that turns any treadmill into a smart treadmill with speed, cadence and incline.
What Is Runn?
Smart treadmills are certainly a luxury piece of equipment yet as Zwift becomes an ever more important training tool for many triathletes, being able to run on the platform is an alluring proposition. For those who already own a ‘dumb’ treadmill or can’t justify the expense of a smart treadmill, there’s the Runn treadmill sensor.
A lightweight unit that sits at the side of your treadmill’s running belt, the Runn tracks speed, cadence and incline. Speed is calculated using optical sensors which track the time it takes for the included silver belt stickers to pass from one side of the Runn to the other. Meanwhile, an accelerometer measures cadence, by registering each footfall, as well as incline.
All this data is then transmitted by ANT+ or Bluetooth Low Energy (BLE) to Zwift, other apps or smart watches – where the device is registered as a foot pod.
Runn Setup and Calibration
The Runn comes with a simple plastic bracket, which is secured to the side of the treadmill by the included 3M tape. The bracket’s ribbed design allows you set the required height and depth from the belt to get the best readings.
Though the interface between the Runn and its bracket feels quite loose, the unit has stayed in place throughout over 350km of testing – with the exception of when we’ve accidentally nudged it with an errant stride. In this case, the lack of a strong grip means the Runn moves out of alignment rather than snapping off, so it’s a thoughtful design that works really well.
Once you’ve done the physical setup and charged the Runn via micro USB – we just kept it plugged in whenever using the treadmill – you’ve got a couple of options regarding calibration.
The Runn’s speed is pre-calibrated in the factory, so it should give accurate readings out the box. This is likely to be a little different from the speed on your treadmill’s display as treadmill accuracy can vary wildly.
If you’re determined to have your Runn match your treadmill, you can use North Pole Engineering’s Configurez app, which is available for iOS and Android. In the app, you can reset factory settings, update firmware (always a good idea) and calibrate speed and incline independently. The latter is useful as it’s unlikely your Runn will be perfectly level on your treadmill. While gradient’s yet to be fully utilised by training apps including Zwift, this future-proofing gives a little extra peace of mind.
Using Runn In Zwift
When you’re happy with your setup, the next step is simple – log into Zwift, click the run tab and select the Runn as your preferred device for speed and cadence.
Once in Watopia, we found our pace in Zwift wavers slightly – a little up, a little down. The figures in the Configurez app fluctuate in the same way, so it appear that this is simply the Runn reflecting our treadmill’s ever-so-slightly wandering speed as opposed to an issue in Zwift.
In fact, ‘issue’ is overstating it – throughout testing, speed has stayed within a tolerance of 0.1km/h so there’s zero effect on training.
There’s only a lag of a second or two between changing speeds on the treadmill controls and this being reflected on Zwift as the treadmill accelerates. Cadence was spot-on too, giving essential second-by-second for keeping running form in check.
There have been occasional stutters during which our avatar was reduced to an inexplicable walk for a moment before returning to full speed – though it’s always hard to know if this is a Runn, Zwift, ANT+ or WiFi issue. Bluetooth seems to be more stable from this point of view. Whatever the case, it’s been a rare occurrence that’s only been frequent enough in one session to irritate us into throwing in the towel.
On the whole, though, running with the Runn has been a great experience. Setup is simple and it’s easy to use, consistent and stays within a commendable accuracy tolerance. It gives all the benefits of a footpod without having the bother of switching a device from shoe to shoe – ideal for those who like change-up their shoes regularly and particularly good for multiple users sharing a treadmill.
On top of that, the Runn represents exceptional value, giving smart treadmill features to any existing hardware without a colossal price tag.