Low heart rate at rest, high heart rate at exercise

[velizondo]

I´ve read a question like this before although I am older than the other post.  I am a 33 year old female, about 125 lbs, 5,4.  I´ve been running for 16 years, but have in the last year been paying more attention to my heart rates.  I´m always running at a pace of about 6.5 - 7mi/hour.  I usually run for about 45 to 50 min, 6 to 7 days a week.  I have a resting heart rate of 60, but when I run, my heart rate goes up to 170 towards the end of my run on a flat run, or even the higher 180s if it´s a steep incline.
At 170 I do not feel exerted or tired and can talk pretty good(although a full blown conversation is probably no a good idea).  A recent "fitness test" done at my gym resulted that my max heart rate is 200, but I´m still concerned.  I have always been an athlete and so I am used to pain and going further than what feels comfortable.

I had a complete physical 2 months ago, with a stress test, and the Dr. said I was in perfect health.

Is it possible I have some tachydysrhythmia triggered by exertion that did not show up in such an easy stress test?

[velizondo]

Hey Brooke,

Thanks for your answer.  I talked to my doctor and he asked me to keep my normal routine, but he want me to have a Halter? for one 24 hour period so he can monitor all variations.  He says it might just be that I have a very high heart rate by nature, so I´m waiting to be scheduled to be fitted with this device.

What I really don´t yet get is the association between heart rate and cardiovascular fitness.  I´ve always tought the fitter you are, the slower your heart has to pump to meet your oxygen needs, so the normal thing to expect would be to have a lower heart rate, rather than higher if you do so much aerobic exercise.
I guess as a fitness freak (although it seems I don´t read enough about it) I hate to think that my heart does not behave as it should.

V.

[Brooke_38]

Hello...

According to everything you have posted in your question, including the results of your recent physical which included a stress test, in my opinion you seem to be a really good shape.

If you go by the Target Heart Rate calculator during exercise (220-age) your THR is 187. There is some really good information on this at the American Heart Association...I am pasting the link here, you will have to copy and paste it in order to access the site.

I hope that you find it useful:)

http://www.americanheart.org/presenter.jhtml?identifier=4736