Great sense of achievement in running for 20 mins non-stop but max heart rate went to 190 and average was 157. Should I be worried? Having never really been able to run before I`m trying to get to 3 miles in 27 mins before I'm 52 which is 4 weeks away. Loving the programme but was really apprehensive before today but I surprised myself. I'm tracking my progress(?) in a spreadsheet and before today trends were improving ie expending less calories per mile. I run on a treadmill with an incline of 2 so am hoping I will cope with the great outdoors once I've finished.