+/- increase or decrease intensity during workout

The + / - button allows you to change the intensity of the workout on the fly without stopping.

This is on a PC with the Windows edition.

On a Mac, the +/- buttons don’t do anything. 

So where is it ? 

Simple question, but I can’t find the answer.

Thanks.

Olivier.

You can always use the Zwift Mobile Link app. But if you are not able to use that the + and - should work on a Mac:

https://support.zwift.com/hc/en-us/articles/208467596-Using-Workout-Mode