Thank you all so much for the replys. I still have to wait a couple more months to get outdoors with my bike (I hate riding in the snow) and try out the 15 min brake because in a spinning lesson that just wouldn't make any sense

I have noticed though that when I take one song easier with lighter pedalling I will "recover" and am then able to drive as hard as beofre if not even harder! So there's like this obstacle and once i'm over it it's all good

I had to read the texts about two three times before I was able to completely understand it since English is not my mothertongue and it was all this scientific stuff. Luckily I study at the moment in English stuff like chemistry and mechanics so this is all very good practise for me in that sense as well I might still read it couple more times just to be on the safe side