Assuming that there are no physical problems, I like running the best. As far as the 10 min or 3 laps thing.... Is that all? As far as the biking, it's easier on a beginner to split sessions instead of going all out. Really, you should try 30-45min 3-6 days a week. If you find that you can't stay going for the whole time, you are going too hard. Drop the intensity to a steady pace you can maintain.
