When using any type of cardio equipment, you should start off slow because there is always the chance (a good chance) that you would end up overexerting yourself. I don't use a bike and I do have a treadmill, still, what was mention still applies. When I started off doing my HIIT, I have actually started doing intervals that never exceeded 5 min (10 min will never really produce the best results, if any) but that was how I started off. Once I was
used to that amount of time, I added only 2 mins. I continued this cycle until I reached 20 min, and by then I was doing at least 20 min of HIIT every 6 days and the results were quite nice. (you will not lose more than 2 pounds of weight a week or in other words, muscle,
if you have a proper basis for your nutritonal needs)
My words of wisdome: Start off slow & low (intensity)