Question about heartrate during intervals.....

[win1jam]

I just wore my Polar monitor for the first time today and did Imax 2. I noticed that during the interval blasts (particularly toward the end of the blasts)...that my heartrate would go as high as 90-95% of my heartrate range...once, it even went to 98% (interval 9, lol). A friend of mine thinks it's bad for my heartrate to go that high...and that it could be releasing cortisol. Does anyone know at what heartrate cortisol is released? And is there a particular heartrate that I definitely shouldn't go above (95%?).

thanks in advance!

Jamie

 

[kathryn]

I think heart rate zones are not that accurate unless you've had a stress test or something by a doctor that will show you exactly what your heart rate zones are. Otherwise, there are several forumula to figure APPROXIMATE heartrate zones. Some of them have a different formula for men and women.

I would take the info on your heart rate monitor with a grain of salt, ad paire it with "how do you feel." As in the old "perceived exertion" chart. On a scale of 1 (complete lack of effort) to 10 (all-out, couldn't do any more), where do you feel you are when your monitor says you are at 98% (about to keel over, if it is accurate).

I don't know if cortisol production is that related to heartrate. It IS related to stress, which can come at any heartrate. (Even worrying about your hear rate might cause some people enough stress to release cortisol, LOL!). And from some info I've seen, cortisol is not all bad.