Please educate me...

I got a Polar F6 Heart/Fitness Monitor for Xmas, and have been wearing it to all my classes. But here's my question:

I seem to spend most of my time at the top of my heart rate (my max is 180), and sometimes a little over. According to my watch, my time at moderate is pretty low, and at hard is very high. No matter what kind of class I take (Kickboxing, Weight Lifting, Arc) I burn about 450 calories (give or take). I'm at the low end of what they estimate you should burn.  Some classes I feel like I worked harder than others. But, I always feel good; I don't feel like I'm at my max. I'm breathing hard, but not uncomfortably so (does that make sense?). I can still talk and stuff. I've got a good sweat, I feel good after.

A lady about 15 years older than me, and probably 20 lbs lighter burns 200 more calories than me, stays on average around 165 bpm, and is working as hard as me. I know this is a little of comparing apples to oranges, but here's my question:

Am I working too hard? Do I throw by jabs and hooks too hard? Am I getting too into it? I'm just having fun, but I feel like the I'd burn more calories just going for a walk around the block! Is it possible my body is just happy operating like that? Or could I be burning more if I calmed down a bit?

While my clothes fit better, I'm not really losing my fat. My diet is good, though every day I try to be better. But, I'm beginning to feel like my exercise isn't helping as much as it should. I go every day. I feel like I should be looking better for all my effort! Thanks!

First, I'd recommend that you re-read your owners manual to be sure you have you HRM set up correctly.  Second, going easier is not go to burn more calories, going harder will burn more calories.  And third, you might want to read this article about HRMs and zone training.

OK, thanks....I'm going to read the article right now.

Others at my gym with whom I've discussed this have all said to make sure my settings are right...I'm going to do it again this weekend, but I've doublechecked everything and it seems right. Like I said, I'll re-do it anyway.

Great article...I will try one of those Sub-Max tests too. The article's "Best Fit formula" lined right up w/my rate found from the age predicted test.

Thanks.

You are on the right track!  Everybody's HR is different.  Those formulas that just use age and weight don't work.  I just calculated mine with one somebody claimed to be the "best", and it was 10 beats lower than the maximum I've seen actually running in a race.

I don't like that sub-max test either.  It really depends on how fast/hard you walk.  I prefer the lactate threshold tests used by endurance athletes (runners, triathletes).    Those are a little harder though because you would need to run for thirty minutes to get that one. 

Here is an interesting article on how to determine your MAX HR in five minutes, provided you have a good hill :-)

http://www.marathon-training-schedule.com/max imum-heart-rate.html