Hi I have a question that I cannot find any answers to anywhere in Zwift.
On the left of the zwift screen whilst training, there is a guide as to what part of the training session you have scheduled you have completed. If you have hit all the numbers you get a yellow star. BUT at the bottom, there is a 100% plus-minus control I have attached a screen shot with the section circled. Can anyone at Zwift tell me what this does and where the instructions relating to it are please?