HRM calories burned seem huge!

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k1979k
k1979k Posts: 94
in Fitness and Exercise
I have just invested in a Polar FT4 HRM. I wore it for the first time tonight, after setting it up, and it showed calories burned to be 555 for an interval boxing session and 610 for a 1 hour session of Zumba.

This seems excesive, as using MFP I usually calculate the boxing (using 'boxing on bag' 30 mins) at around 200 calories and being my first session of Zumba I wasn't going really hard as I was figuring out the moves. MFP worked it out at around 250 ('dancing, aerobic, ballet or modern).

According to MPF I killed around 550 calories but according to my HRM it was 1100 calories. I don't know what to think!! Particularly if I'm going to eat my exercise calories!

Any thoughts??

Replies

  • starstealing
    starstealing Posts: 104
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    so you did a total of 2 sessions?

    if so, then go with that last hrm amount.
  • k1979k
    k1979k Posts: 94
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    Yes, 2 sessions - MFP says 550 (ish) for both, HRM says 1100 (ish) for both. That's a big difference...
  • DaveyGravy
    DaveyGravy Posts: 283 Member
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    Always believe your HRM rather than this site's calorie information. Your HRM has more information about you and has your heart rate to work from too. The classes you have done are bound to burn some serious energy, I think the HRM is probably accurate.
  • CombatVet_Armywife
    CombatVet_Armywife Posts: 300 Member
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    I had this same question not long ago. My treadmill work out usually burns 400 calories, then one day I decided to put my HRM to use. I only used it a few times previously because I didn't like the way it felt while working out. The calorie difference was staggering!! For the 400 calories burned according to my treadmill, my HRM showed 790. I was floored by the difference and didn't know what to think.

    The feedback I got was to go with the HRM since it actually reads your heart rate and THAT is what determines how many calories you burn. The higher the heart rate, the higher the burn. It still seems like such a huge amount, but I go with my HRM. To be safe, I still only eat SOME of those calories, just in case! I seem to be doing okay, since the change, my weigh-in showed a 3lb loss. Wish ya luck! Figuring out what works for you can be the challenge. I hope you get the feedback you need to help you out! :smile:

    On a side note: I seem to notice, and have been told, that MFP's calculations are generalized estimates. Age, weight, and height will all be factors as each person is different.
  • Natalie43
    Natalie43 Posts: 122 Member
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    make sure your personal details were input correct, and if they were, i would trust your HRM.:smile:
  • erickirb
    erickirb Posts: 12,293 Member
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    when using your HRM remember to back out the calories you would have burned at rest anyway as those calories are already included in your base amount. Lets say you worked out for 90 minutes and on average you burn 1.5 cals per minute at rest you would take the 1100 from your HRM and back out 135 (90minx1.5cals/min) and enter 965 into MFP.
  • ambercole
    ambercole Posts: 426
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    That sounds about right to me. I have a Polar f6 and i burn around 650 calories an hour doing cardio.
  • mzenzer
    mzenzer Posts: 503 Member
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    As everyone has said, go with the HRM. an hour long P90X workout for me averages about 1000 calories burned.
  • lucifa73
    lucifa73 Posts: 110
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    I go with the HRM I use but I only log about 75% of the calories - firstly to take out what I would have used anyway, even if I'd sat on my (slimmer) *kitten* instead and secondly to allow a 'safety' in case I've underestimated calories eaten somehow (surprisingly easy to do!)
  • Sabs_21
    Sabs_21 Posts: 65 Member
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    I agree with what everyone else is saying. I was surprised with my HRM results but it calculates your age, height, etc. with your heart rate so it's more accurate than the general information here. Not everyone burns the same amount of calories doing the same activity. And 600ish for Zumba sounds about right according to what mine reads after a class.
  • TrainingWithTonya
    TrainingWithTonya Posts: 1,741 Member
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    You have to watch HRM's in that they can overestimate calories burned if your heart rate is already elevated by medications and caffeine as that elevation in heart rate isn't actually resulting in extra calories burned by the muscles for exercise.
  • k1979k
    k1979k Posts: 94
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    Thanks everyone – very helpful responses! And glad to see others have had a similar experience – gives me a bit more faith in what my HRM is telling me.

    I realise MFP calories are a bit of an average, although I thought it still took age and weight into consideration. It does make sense that the HRM values are more accurate but it was a bit of a shock!

    Also, thanks for the tip to take off calories that would have been burned anyway - I hadn’t thought of that (or the caffeine/medication factor).

    I think my main concern was eating my exercise calories – I didn’t want to go and eat 1000 ‘extra’ calories if it wasn’t accurate! That said I rarely eat all my exercise calories anyway, but if I’m burning this much then perhaps I should eat more of them. I might, as someone suggested, stick with logging around 75% of what the HRM says to allow room for error, and bumping up what I eat (however I still don’t think I’m going to eat an extra 750 calories... that’s a bit hard for me to take in at the moment! I’ll see how I go – a bit of trial and error I think...)

    Thanks again everyone :smile:

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