I am 25 years old, 145lbs and have been trying to get back into shape. While on the treadmill my H.R. is around 180/min which is well over my target H.R. and seems high on the H.R. chart. I'm running at 7.5 MPH for 25 minutes (3 miles+/-) and I feel fine during and after and my resp seems normal too.

I am just wondering if it is safe to be running at such a high H.R. Do I just have a physiologically faster excercising H.R.? Should I reduce speed lower to match my Target even if I feel like I'm under exerting myself?? Thanks for help!!

Have a look at the thread below which is also on this forum page.

"New formula for estimating max HR "

It might offer a liitle insight to your question.

Depends on your current health...

If you haven't already, get your regular check-up done and inform your doctor that you are participating in a regular exercise program. If you have high blood pressure, or some form of heart disease, then you may want to take it easy. However, if you have a clean bill of health and are comfortable at 180 bpm, then by all means continue at that heart rate.

The equation for determining your "suggested" target heart rate zones is:

65% Max Heart Rate = 220 - your age - your resting heart rate x .65 + your resting heart rate

85% Max Heart Rate = 220 - your age - your resting heart rate x .85 + your resting heart rate

* Your resting heartrate is the beats/minute taken in the morning without having gotten out of your bed or woken up to an alarm (In other words, waking up calm and relaxed). This will tell you how hard your heart is working at its most "relaxed" state.

But like I said, if you are comfortable at 180, then continue to use that HR as calorie expenditure will be higher at that heart rate...