With the fitting idea you’ve been given by Irider, the difference between fitness cycling and, well the other kind will be how far, you go, how fast you go, and hard you push the pedals. The fit, either self done or done by an expert, will mainly affect how much you can do before discomfort sets in. That trial and error will give you experience to evaluate your situation and your next steps.

I also like what Kontact suggests. I think through those same conventions when I have a fitting problem on one of my bikes.