So, I finally have a gym membership (though school). Yay! And I have started measuring my heart rate using those machines, and during the most intense part of my work-outs, I measure between 175-180, and the machine tells me that I'm exceeding my maximum heart rate. The Mayo Clinic heart rate calculator tells me that I shouldn't exceed about 158 beats per minute. My resting heart rate is about 75 beats per minute.

Do I really need to worry about this? I try to do high intensity interval training (though I'm not so good at it yet), and during the 30 minutes or so when I'm not warming up or cooling down, I cycle from about 155 - 175. I feel like I need to push myself hard so that I can burn the most calories possible in the amount of time I have to exercise, and honestly, sometimes I don't think I'm pushing myself hard enough.

I'm 34 and in good health generally (except, of course, for the obesity risk factor). Am I okay to continue to ignore what strikes me as just another obstacle in getting rid of this weight?

Oh my numbers are always higher I don't particularly care. I'm sure part of it is due to high blood pressure but the only thing that can help that is to keep losing weight...

Maximum HR is just an estimate. And if you hit YOUR true maximum heartrate, there is NO WAY you wouldn't know. It's a very distinct physical feeling. People testing their MHR have to wear something that records heart rate, rather than just displaying it, because when you hit it, you can't even read a heart rate display.

As long as you don't feel like you're going to pass out, you're good.

Thanks to both of you! I am grateful that I don't have to worry about it - I got enough on my mind! (And it is so GREAT to see you still so successful, Amanda. Gives me lots of hope that I will get there again and stay there!)