questions about HRM

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I just picked up a Polar FT4 Heart rate monitor and have a question as far as how I should log it. Is there a percentage error I should remove when logging it?

For example i just got finished working out and these are the stats:

Duration: 21 Min
carories: 311
average heart rate : 156
max heart rate : 167

Should i log 311, or deduct some to get a more accurate log? Or are the monitors pretty accurate?

Replies

  • WalkingAlong
    WalkingAlong Posts: 4,926 Member
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    Anything over 10 calories a minute makes me suspicious, unless you're very obese. I would at the least divide your BMR by 1440 minutes in a day to get a rough per-minute BMR estimate and subtract 21 times that from the 311. So if your BMR is around 2000, subtract 1.4 X 21 minutes, or around 30 calories.
  • AllanMisner
    AllanMisner Posts: 4,140 Member
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    They are estimates. For example, my heart rate could be the same, but if I weigh 50 lbs more than you, I could be burning more calories for that effort. Or I could be in worse shape and be burning less.

    I do it like this: I take the reading and subtract 100 calories per hour (assuming my resting metabolism was approximately 2000 or nearly 100 calories per hour). This gives me a conservative base. I tweak it from time to time if I'm not seeing the fat loss I should be based on the numbers.

    Think of it like a speed-o-meter without numbers. You get a feel for where 65 mph is and go with it until you get more data that tells you it is too high or too low for that type of activity (roadway speed limit).
  • Mr_Knight
    Mr_Knight Posts: 9,532 Member
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    It depends on the exercise, and your level of fitness. If you're reasonably fit, and the exercise was a 20 minute jog, it's probably not far off. If it was an Insanity (or whatever) workout, it is probably way over-estimating and you're better off cutting the number in half.
  • bperkins88
    bperkins88 Posts: 357 Member
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    my BMR is 2055.2 apparently?

    5'7, 210LBS 25 Years old

    It was 21 minutes of Jumping Rope
  • WalkingAlong
    WalkingAlong Posts: 4,926 Member
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    http://www.mayoclinic.org/exercise/ART-20050999

    According to that table, your HRM might be about right. They list rope jumping as the same intensity as running 8mph, so it'd have to be pretty dang intense, I think.
  • bperkins88
    bperkins88 Posts: 357 Member
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    what is a good average heart rate to burn calories efficiently ? Is 156 a good number, or should I try to go a little harder next time
  • lucan07
    lucan07 Posts: 509
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    I work out at about 80% of my max heart rate because I can keep that rate up as long as I want, I also convert HRM calories to net removing calories you would have burnt anyway doing nothing using this calculator

    http://www.shapesense.com/fitness-exercise/calculators/net-versus-gross-calorie-burn-conversion-calculator.aspx
  • bperkins88
    bperkins88 Posts: 357 Member
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    I work out at about 80% of my max heart rate because I can keep that rate up as long as I want, I also convert HRM calories to net removing calories you would have burnt anyway doing nothing using this calculator

    http://www.shapesense.com/fitness-exercise/calculators/net-versus-gross-calorie-burn-conversion-calculator.aspx

    thanks!
  • WalkingAlong
    WalkingAlong Posts: 4,926 Member
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    what is a good average heart rate to burn calories efficiently ? Is 156 a good number, or should I try to go a little harder next time
    The number will vary for everyone. I agree with pick a zone based on your max, or just use perceived exertion. You don't want to be able to easily sing but you don't want to be unable to talk in short sentences. And don't overthink it. The harder you work, the more you burn but the shorter you can go because it's uncomfortable. There are no magic zones and no dangerous ones.