Which number is right?

ErrataCorrige
ErrataCorrige Posts: 649 Member
edited September 21 in Fitness and Exercise
Arg! I finally bought an HRM and was super disappointed that my calories burned for my workout was well below what I thought it to be. I did 24 minutes on my elliptical, doing a random difficulty program. My machine says I burned 275 calories. MPF says 252. But I was really surprised when my HRM said I only burned 180!

I am using a Polar FT7, which, from what I have read, is pretty reliable.

Has anyone else experienced this? Is my HRM right? Have I been underestimating my calories burned for the last four months?!?

Replies

  • LuckyLeprechaun
    LuckyLeprechaun Posts: 6,296 Member
    yes, most likely you have been. The good news is...now you have a HRM which makes your estimates closer and that's something to smile about!

    the calories in food are estimates. They can't state with absolute accuracy what every single piece of food is worth.
    the calories burned on your HRM are estimates. They can't calculate with absolute accuracy what your body burned that particular day.
    do your best and it will all work out beautifully.......:flowerforyou:
  • Your HRM will be the most accurate. Mine is always WAY lower than the site says.
  • jrich1
    jrich1 Posts: 2,408 Member
    Go with the HRM, its the only thing hooked up to you that can measure how how you are working. That sounds about right, my wife usually burns about 350-400 in 45min.
  • ErrataCorrige
    ErrataCorrige Posts: 649 Member
    Ugh, guess I better go get back on. :)
  • My HRM is way lower than the machines too. I was sad at first, but it is what it is.
  • I know that Brenda has one as well and she swears by it. Its also a polar. I want to get one!
  • Azdak
    Azdak Posts: 8,281 Member
    HRMs --even the good ones--are not direct measuring tools, nor can they operate at an optimum level by themselves. You have to set them up properly. That means maximum heart rate and VO2 max need to be as accurate as possible.

    If your HRmax is higher than the "200-age" number, the HRM will OVERestimate your calories.

    If your VO2max is higher than the preprogrammed number that comes w/the HRM, it will UNDERestimate your calories.

    It's a mistake to pull an HRM out of the box, strap it on and then start using the data to plan your workouts or eating plan.

    Do the fitness test included with the FT7--it's kind of goofy, but it can be helpful for a lot of people.

    Look at some of the calculated "zone" target HRs, and then compare those numbers to your feelings of perceived exertion when you are working out. If the HRM says you are working at, say 85% of HRmax, and you feel you are just cruising, then your true HRmax is probably higher than what is programmed into your HRM.

  • Do the fitness test included with the FT7--it's kind of goofy, but it can be helpful for a lot of people.

    How do you do the fitness test on the FT7? I own one as well, and I looked through the manual and googled it as well, but it seems that only the FT40 and higher models are including this fitness test feature.. Please share =)
  • lethwin
    lethwin Posts: 18 Member
    Thanks for the info Azdek. I've been wondering if my HRM is over-estimating. I got it a few weeks ago and expected it to show lower calories burned than the machines(since that is what I see most people commenting on). I found, to my surprise, that it was reporting much higher numbers. I have a HRmax of 185 (I base this off a treadmill stress test I did a few weeks ago which took me as far as I could go) which is higher than 200-age(42). I do have the HRM programmed with this max hr, but I dont have a way to program in a VOmax(much less try to figure out what mine is). Its kind of a bummer. I bought the HRM so I could get more accurate calorie burned readings and its seems it was a waste of money. I've been doing the zone training, so at least its good for making sure your in the correct zones and they seem to be accurate with regards to level of effort. I guess for now I'll just take the calorie number as a grain of salt and make sure I dont eat up all the calories the HRM is telling me I burned.
  • PJilly
    PJilly Posts: 21,991 Member
    I didn't have an HRM when I started here. I used MFP's estimates, and I happily lost a pound a week that way. Then I got an HRM, and like you, the estimates it gave me were considerably lower. I used those for a while, but I was miserable and hungry. Then I got the bright idea to put the HRM in a drawer and go back to what was working for me before I got it. The lesson for me is that if I choose a method and am consistent with it, as well as consistent with tracking my food, it's pretty easy to tell after a few weeks if adjustments need to be made, either up or down.
  • Azdak
    Azdak Posts: 8,281 Member
    OK, it would seem I was mistaken. I apologize. When questions come up about specific Polar models, I look up the user manuals online to check for the specific features they have. I thought I had read the FT7 and had also read that it had all of the features of the F6.

    It appears that my memory was faulty and the FT7 appears to lack not only the Fitness Test, but the ability to manually enter VO2max as well.

    Without any way to differentiate individuals by fitness level, I am at somewhat of a loss to explain how they calculate calories. Anyhow, my apologies to everyone.
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