Prescriptive power for training sessions

I would like the ability to set a prescribed power output for the “riders choice” training rides (or create a new category) for use with my ergo capable trainer.

As an example, you should be able to dial in 200w and have Zwift and the trainer keep you at 200w using trainer resistance. It would be nice to have the prescribed power setting adjustable while you are in session so that you can adjust based on fatigue or to suite exactly what it is you are trying to achieve per session. 

That is exactly what I was looking for in the new Workout mode…!

Depending on what trainer you have chances are there will be an app which can do that for you.

How would such an “app” integrate with Zwift? Does the actual mobile app for Zwift on iOS, which has some ominous “BLE Sensors” settings, give us a hint?

There is no need for any additional app. This should just be a feature within the settings of Zwift - preferably part of an interactive on screen menu which additionally can be controlled via the existing Zwift app.

The capability exists already within smart trainers and its how Zwift already controls resistance. Zwift simply need to give us an interface into that capability. 

I see what you are saying Kai. I may be able to disable Zwifts control of my trainers resistance and then use the Wahoo app to set a resistance. I’m going to give that a crack right now.

My feature request remains though as I would like to see this integrated into Zwift. 

I do agree that it should be integrated. Just saying that firstly, you don’t have to wait for that to happen as chances are you can do that today with a big of reconfiguration and downloading an app. And secondly I wouldn’t expect it to be a priority given that doing it with an external app is feasible.

The app required depends entirely on what trainer you have. For a kickr then the Wahoo app, there’s the Tacx Training app for Tacx trainers.

I haven’t tried the riders choice ones yet, does that not control power at all and instead just leaves it free?

For a set erg mode wattage, you could try doing one of the long endurance rides (like in the your first century plans).  You can temporarily use the slider to adjust your FTP so that the workout is at whatever wattage you like.

Also, on the upcoming features list is the workout creator which sounds like it will let you do whatever you want.

Confirmed you can disable resistance in Zwift and then dial in whatever wattage you want to train at from the Wahoo app on your phone. It works perfectly.  

I was expecting the same from the riders choice, especially since there is an option “ERG Mode”. But I tested it twice and it simply followed the terrain, resistance-wise…

Zwift has said that a workout builder is in the works.  When that is done one option would be to create an ERG workout at 200w and use that.

You can already do that, by choosing free ride and changing your FTP. The question is in relation to being able to change the level of the ERG mode while you are riding. Which is where the trainer apps come in.

In my experience free ride does not work like that. Free ride still responds to the terrain of the map to control resistance contrary to the description of what free ride states.

No matter, you can achieve what I was after as I have mentioned above. 

Jason, how did you disable resistance while still being able to watch yourself in the Zwift environment?

Hi Mate,


Go into Zwift settings and there is a slider bar named something along the lines of “trainer resistance level”. Set that to zero, or off (can’t quite remember)

Now open the Wahoo Fitness app on your phone and navigate to the third screen, select “erg” and then set the Kickr target power to whatever wattage you want.

Start pedaling and you are away. You can adjust your wattage at any point by using the app.

Jason, your instructions worked perfectly, thanks!  I can now adjust my wattage with Wahoo while riding in Swift.