Hello! So I did my first week 4 run yesterday and managed to keep going for the full two lots of 5 minutes. I can't help feel I'm running too slow, feel I probably power walk faster! I know loads of posts say to keep it slow but how slow is too slow? I've got a fit bit and heart rate is always in cardio and peak for most of the run so I'm guessing that's a sign in going fast enough?