Understanding Virtual Speed in the SYSTM app

When connecting your sensors, if you're connecting a smart trainer or power meter AND a speed sensor (or your trainer reports speed), you will have the option to choose speed reported from your sensor or to choose Virtual Speed.  Virtual speed is calculated based on your power output and more closely represents outdoor speed than straight speed reported from a speed sensor. 

What Is Virtual Speed?

We have created a formula that uses some simple physics equations to calculate speed from your power data. We use Virtual Speed to calculate the distance for your ride.

How Does The Formula Work?

We are starting with a simple model that calculates speed from power instantaneously. Here is what we use to calculate it:

  • Current Speed - From the sensors you have connected to SYSTM (when applicable)
  • Power Output - From your smart trainer, power meter, or virtual watts setup
  • Rider Weight - From your profile information
  • Bike Weight - 9kg
  • Rolling Resistance - 0.005
  • Head Wind - 0kph
  • Temperature - 0 C
  • Elevation - 0 Meters
  • Position - Hands on the hoods


How Does This Affect Me?

  • If you have a power meter that doesn’t report speed, this means that your rides will now show as having speed and distance in other apps.
  • If you have a power meter, smart trainer, or Virtual Watts trainer, the speed and distance reported in the .fit file to other apps will now use Virtual Speed.


Why Did You Change How Speed And Distance Were Being Calculated?

We added this Virtual Speed formula in an effort to create more consistent speed and distance data no matter which equipment you use.  Some users (with power meters) have never been able to show speed or distance when using The Sufferfest App.  Other users with smart trainers end up with some pretty crazy speed numbers.  It is difficult to go in and address each of these specific situations so instead, we have found a way to level things out a bit.  As we gather more data we will continue to improve the way that this formula works.

Can I Disable Virtual Speed?

You can select speed from a sensor or smart trainer that you have connected to the app as long as you aren't using Virtual Watts.  Virtual Watts users don't have an option to disable Virtual Speed.

How Do I Disable Virtual Speed?

Open the device connections menu and connect your trainer and sensors.

You will notice that Virtual Speed is enabled by default.



Now click the speed icon next to your smart trainer or speed sensor


Now the app will use the speed supplied by your smart trainer or speed sensor instead of Virtual Speed.