In the workouts I am doing Zwift tells me to ride at 90-100 rpm, however I notice that I am regularly exceeding this, sometimes going up to 110rpm. Is this too fast? Is there any difference in the training if your cadence is much faster than that recommended in the workouts (FYI I’m 6 week FTP builder training plan)?
People will tell you lots of different things about cadence. But the bottom line is you should spin at a speed that is comfortable to you.
If you find 110 comfortable (and I assume that’s what you’re getting at) stick with that. The only time you should try and stick to a lower cadence in a session is when that is the aim of that workout - for example specific low cadence work with high resistance, or in warmups where 100+ is often employed.