For some time, the standard way to get your avatar to move in Zwift Run has been to wear a footpod: a small device attached to your shoe which transmits various metrics including speed and cadence to Zwift. But it’s not the only way to get your in-game self moving! In this article, we’ll take a look at the growing popularity of Smart Treadmills and consider the advantages or disadvantages of this and other connection methods.
Footpods have been around for many years. In outdoor running, they were originally used to accurately measure a runner’s steps per minute or cadence. They are also useful for measuring distance covered when a runner is out of contact with a GPS signal, perhaps in a tunnel or heavily wooded area.
The older footpods use ANT+ technology and were very basic units. More recently Bluetooth footpods have emerged, packing all sorts of measurement components inside. Accelerometers, barometers, gyroscopes and magnetometers all combine to provide myriad running metrics such as ground contact time, vertical oscillation, running ‘power’ and accurate distance measurement that is arguably as good as GPS.
Using a Footpod in Zwift
You can use any kind of footpod to run on Zwift, including (of course) the Zwift RunPod. Depending on what device is being used, the Zwift app will read data from an ANT+ or Bluetooth signal and use it to provide speed and cadence in game.
If you are using a modern computer (Mac or PC) running the latest operating system, then you can use a Bluetooth or an ANT+ footpod with a USB ANT+ receiver. If you are using a mobile device or AppleTV you can also use Bluetooth or ANT+ but you will need a bridging device to convert the ANT+ signal to Bluetooth.
The main advantage of using a footpod is portability. You can take your footpod anywhere! If you are a frequent traveler you can happily take your footpod to the hotel gym, log in to your account and be running in no time.
If you don’t have a treadmill at home, having a footpod (and smartphone or iPad) will allow you to use your local gym to run on Zwift as long as there is an Internet connection.
In addition, you don’t need to buy a footpod for every member of your family who runs on Zwift. Because Zwift stores the calibration setting for a footpod in your personal settings rather than on the footpod itself, you can swap it between shoes and know that when you log in, your own personal calibration with be retained.
The main issues with footpods concern consistency and accuracy. Many people complain that when they use a footpod, their speed in the Zwift app does not match the speed on their treadmill display. Frustratingly the speed on Zwift is usually slower than the treadmill.
If you are in a workout where there are set speeds at which you are required to run, this can be annoying, because you will often find yourself running faster on the treadmill just to keep pace with the workout.
Furthermore, the speed is not consistent. Although your treadmill might be set at a constant speed, the display in Zwift will vary considerably while you run, often jumping above and then below the set speed.
There are a variety of reasons for this. First, your leg is not a machine, so your speed will vary slightly on every stride. Second, and most significant, is that your treadmill works in a specific way which may trick your footpod.
Your treadmill is powered by a motor. Depending on how powerful the motor is, some treadmills will see a significant slow down of the belt when your foot impacts on each stride. To counter this, the belt will speed up slightly when you are fully in the air.
So on average, the treadmill is indeed moving at the pace it is displaying. However, the footpod only measures the slowing down of speed when impacting the belt. It does not measure the speeding up of the belt when you are in the air.
Arguably this is a more accurate measure of the ‘speed’ at which you are running. But it does mean that the speed displayed on your treadmill will be different from that registered by the Zwift app.
A smart treadmill is one that can send and receive a Bluetooth signal. This means it can send speed and sometimes cadence data direct to Zwift, without the need for a footpod.
It is also possible for Zwift to send instructions to the treadmill. So for example, Zwift could automatically increase or decrease the incline of your treadmill in line with the elevation profile in game. (This has yet to be implemented in Zwift, but it remains technically possible.)
The major advantage is the consistency of the speed reading. The speed displayed in Zwift will always match exactly the speed displayed on your treadmill. Now, whether this speed is an accurate measure of how fast you are actually running is another matter, but it is very satisfying to see the two match up.
The other significant advantage is fewer points of failure. Fewer pieces of tech to get in the way of your run. If you have a smart treadmill which also measures cadence, you will have no need to use a footpod at all. Therefore, less kit to fiddle with before you run and fewer things to go wrong.
As alluded to earlier, this beautifully matching display may be very satisfying psychologically. However, the issue of the belt slowing down on impact still remains. Furthermore, if I change the speed of my treadmill from say 10kph to 15kph during an interval session, the speed displayed changes immediately on the treadmill and on Zwift. However, it takes the belt and motor significantly longer to react and get ‘up to speed’. So while it may appear that I am running at 15kph, in reality I won’t reach that speed for a few seconds.
Of course cost is the other major disadvantage at present. Prices are coming down, and will continue to drop, but a good smart treadmill is a significant investment. However, if you are a regular treadmill runner and user of Zwift, it may well be a ‘smart’ investment.
Other ways to connect
There are a few other ways to get your speed into Zwift. These methods are not officially supported by Zwift, but have been reported to work by the Zwift Run community:
- Headphones: some makes of earphones, such as the Jabra Elite, contain an accelerometer and will transmit a Bluetooth signal which can be used as a speed source.
- Chest Strap: some people use the TickrX heart rate strap which also has an accelerometer to measure and transmit speed to Zwift.
- Treadtracker: unfortunately the Treadtracker has been discontinued but may still be available to purchase used. It is a device that measures the speed of the belt on your treadmill using a small wheel placed under the treadmill, touching the belt. The measured speed is then sent to Zwift via Bluetooth.
- Treadmill Smart Speed (TSS) app: there are a couple of apps developed by Zwift users that allow you to manually input the speed of your treadmill on one device and have it transfer via Bluetooth to your Zwift device.
Of course, there are pros and cons to each of these alternatives. Accelerometers in shoes, headphones, and chest straps can be frustratingly inconsistent with frequent dropouts, lost connections, and erratic speeds. The Treadtracker was always difficult to purchase and is now discontinued, and the various apps all have to be manually operated.
This is an ever-changing area of interest. Smart treadmills seem to be an industry focus at the moment, and as Zwift Run grows prices are sure to continue falling, making these units ever more accessible to Zwifters.
However, there are developments moving away from smart treadmills which might provide a more cost-effective answer to the challenge of getting a satisfactory measure of your speed on the treadmill into Zwift. Keep your eyes and ears on the Zwift Runners Facebook page and we’ll see you on Watopia!