Umm WTH how did I go over my MHR

Your true MHR depends on a lot of variables that can't be taken into account with an equation (which I'm assuming is how you determined your MHR, something like 220 - age = MHR). Things like the size of your heart and how efficient it is will also dictate how fast it can go. Also, your HRM might have been reading incorrectly, which can happen under a lot of circumstances.

The calculation on your max HR is just an estimate so it's not really appropriate for everyone. I've found I'm not working as hard as most people are when their heart rate is as high as mine. I can be beating along at 195bpm and easily carry on a conversation because I'm not even winded. I'm not sure exactly what that means, it's just something I've noticed. When I'm running or ellipticaling, I generally keep my HR at 180-195bpm to get a good workout which keeps me breathing normally. When I do sprint intervals to work on my cardiovascular strength, I often get into 205bpm territory. I've learned this is fine for ME (but I also know I shouldn't try to maintain such a high heart rate for more than a few seconds because of the way I feel).

My resting HR is lower than most women, too, at around 52bpm which, from what I understand, indicates I'm in pretty decent cardiovascular shape (when I was really out of shape, it ran around 88-90bpm).

I feel like the best indicator for my max heart rate is how I feel when my heart rate reaches a certain point. When I start to get winded and feel a knot in my stomach, I know I need to slow it down.

Thanks everyone for the information! I'm definitely gonna watch out for that from now on I had no idea that I could go over my max heart rate! This is a very good thing to know.

Actually you cannot really exceed your true max heart rate or increase it. All it means is that your estimate for maxHR is too low and your HRM's estimate of calories will be too high. It appears like your maxHR goes up if you only look at maxHR achievable but you need to be in very good physical shape to get near your true maxHR. So as your fitness improves, the close to your true maxHR you can get.

I am wondering if my MHR will change now that I have had corrective heart surgery. I have not been brave enough to run since I was released from care for full exercise.

I had a hole in my heart which they fixed. We shall see.

I remember telling my MD of 25 years that I got pain in my jaw when my HR hit 175. His response was "Why would you want to get your HR up that high???"

"Cuz I can!" was my reply.

He advised me it is good to mix it up, but not at all neccessary (sp) to work so hard to attain maximum health benefits.

I still do intervals, but at a lower level. If I am ever able to run again I will NOT allow my heart rate to get above the 80%. But that is just me!

Keep up the good work!