My heart rate goes above 170 when jogging at 6.0 with 1.5% incline on the treadmill. Seems high and way above my "target zone" If I went just by my target zone, I would have to walk the entire time. I don't feel too stressed when I am running, but feel like I need to slow down. If I do sprint, I am sure it would be off the charts. I have been jogging for about 2 months now ever other day and was hoping it would maybe go down. Also, this is interval training. Walk for lap, jog for 2 walk a lap, jog a mile, walk a lap, jog a half mile, walk a lap job a lap. So a total 2.25 miles and running 1.5 miles. When I walk in between it goes down about about 137-144 which is still over what my target zone is supposed to be. Suggestions?