how important is heartbeat pm and age .

i am 59 years old and when running at 7.5 k /hr on a tread mill with an elevation of 1.5 my pulse can 144-152 hbpm . i am not out of breath and feel quite comfortable . My resting blood pressureis 120/75 and pulse 55-60 on average . do I need to worry about my pulse rate whilst running. Any feed back will be appreciated.

[Oldgirl Graduate]

I would think thats about right. I watch mine quite closely as I have an irregular heartbeat. Mine can go up as high as 185bpm especially when going up hill. My resting pulse is about the same as yours, I am older too. What is not good is if your heart rate does not return to normal once you slow down your exercise whatever it is you've been doing.

[Hidden]

You sound fine, but I am not your GP, so I would talk to her about it.