Running and calories burned

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tasch79
tasch79 Posts: 17 Member
in Fitness and Exercise
Just a question regarding running and calories burned. I use a hrm and run on a treadmill at the gym for 30minutes. At the moment I’m running about 4.5km (getting a bit further each time) and my heart rate over this time averages about 174 (max 190). My hrm says that I burn about 620 calories. Just wondering whether this seems accurate to you? All the calculators I’ve even seen say that you roughly burn 300-400 in 30 minutes.

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  • brianpperkins
    brianpperkins Posts: 6,124 Member
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    http://www.runnersworld.com/weight-loss/how-many-calories-are-you-really-burning?page=single

    While HRMs can be useful tools, that utility is dependent on the quality of the formula used. Some use more data points than others ... some have the capability to either roughly test or import VO2 measurements ... others don't.
  • Azdak
    Azdak Posts: 8,281 Member
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    The only way you could burn 620 cals at that speed is if you weigh over 130 kg.

    Assuming you weigh less, that means your HRM is substantially overestimating your calorie burn (a fairly common occurrence). The main reason is usually that the person has a true max HR that is substantially higher than the estimated max HR programmed into the HRM.

    If you are running on a commercial treadmill, the calorie counter on the machine will be fairly accurate--it might overestimate by 10%-15% at your speed, but that is still a lot more accurate than what you are getting from the HRM.
  • DaFibble
    DaFibble Posts: 152 Member
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    Azdak wrote: »
    If you are running on a commercial treadmill, the calorie counter on the machine will be fairly accurate--it might overestimate by 10%-15% at your speed, but that is still a lot more accurate than what you are getting from the HRM.

    What about HRMs that take weight and height into account? Mine does (Polar FT4).

    I was under the impression a HRM was the most accurate way to measure calories burned.
  • _Terrapin_
    _Terrapin_ Posts: 4,301 Member
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    tasch79 wrote: »
    Just a question regarding running and calories burned. I use a hrm and run on a treadmill at the gym for 30minutes. At the moment I’m running about 4.5km (getting a bit further each time) and my heart rate over this time averages about 174 (max 190). My hrm says that I burn about 620 calories. Just wondering whether this seems accurate to you? All the calculators I’ve even seen say that you roughly burn 300-400 in 30 minutes.


    At 620 calories you'd be burning 20 calories a minute, unrealistic. An average is for every mile you walk or run is 100 calories. So 4.5 kilos, less then 3 miles, you burned about 300 calories.
  • tasch79
    tasch79 Posts: 17 Member
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    Thanks for your responses.

    Yes I'm 80kg (at the moment!). My hrm is a Polar F11 and I'm using the OwnZone and do the fitness test regularly so that the VO2 measurements are updated. It currently has my VO2 max at 36 (which seems reasonable to me). All my settings seem correct.
  • tasch79
    tasch79 Posts: 17 Member
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    _Terrapin_ wrote: »
    At 620 calories you'd be burning 20 calories a minute, unrealistic. An average is for every mile you walk or run is 100 calories. So 4.5 kilos, less then 3 miles, you burned about 300 calories.

    Hmm. Even though my heart rate is quite high the entire time?
  • Azdak
    Azdak Posts: 8,281 Member
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    PrismaticPixel wrote: »
    Azdak wrote: »
    If you are running on a commercial treadmill, the calorie counter on the machine will be fairly accurate--it might overestimate by 10%-15% at your speed, but that is still a lot more accurate than what you are getting from the HRM.

    What about HRMs that take weight and height into account? Mine does (Polar FT4).

    I was under the impression a HRM was the most accurate way to measure calories burned.

    Most commercial treadmills allow you to enter weight as well (if they don't, then the calorie count is useless).

    As for HRM accuracy, well, I always feel like I am telling kids there is no Santa Claus, but the accuracy of HRM calorie counts is highly, highly, highly, highly exaggerated and overestimated. Most people don't understand either exercise calories or how HRMs work, so they just repeat what they hear from other people. HRM companies have done a masterful job of creating this mystique about the accuracy of their calorie estimates (without ever really saying so).

    Feel free to look at my other blogs at http://www.myfitnesspal.com/blog/Azdak
    for more explanation. In several blogs I go into a lot more detail.
  • DaFibble
    DaFibble Posts: 152 Member
    edited November 2014
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    Azdak wrote: »
    Feel free to look at my other blogs at http://www.myfitnesspal.com/blog/Azdak
    for more explanation. In several blogs I go into a lot more detail.

    Thanks. VERY good blog you have there sir. Reading about HRMs now. If HRMs are only about 80% accurate then I'll drop 20% off my calorie count to be cautious.

    But what's all this stuff about there not being a Santa Claus. :(
  • tasch79
    tasch79 Posts: 17 Member
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    That's a real shame then! However I do only eat half the calories back and I'm losing each week so at least I know what I'm doing is working. Really wish the hrm was accurate; would love to be burning 600+ in 30 minutes! :smiley:
  • brianpperkins
    brianpperkins Posts: 6,124 Member
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    PrismaticPixel wrote: »
    Azdak wrote: »
    Feel free to look at my other blogs at http://www.myfitnesspal.com/blog/Azdak
    for more explanation. In several blogs I go into a lot more detail.

    Thanks. VERY good blog you have their sir. Reading about HRMs now. If HRMs are only about 80% accurate then I'll drop 20% off my calorie count to be cautious.

    But what's all this stuff about there not being a Santa Claus. :(

    Santa got what he had coming for flying during reindeer hunting season. Rudolph jerky = delicious ... and calories from magical flying animals don't count.
  • tigersword
    tigersword Posts: 8,059 Member
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    PrismaticPixel wrote: »
    Azdak wrote: »
    If you are running on a commercial treadmill, the calorie counter on the machine will be fairly accurate--it might overestimate by 10%-15% at your speed, but that is still a lot more accurate than what you are getting from the HRM.

    What about HRMs that take weight and height into account? Mine does (Polar FT4).

    I was under the impression a HRM was the most accurate way to measure calories burned.

    HRMs give a fairly accurate estimate when all variables are entered correctly, and the HRM is worn correctly, and everything is perfect. Even then, the most accurate HRMs are only about 85% accurate, really no further off than the treadmill estimates (although it may be off in the opposite direction, making the difference seem larger.) Calorie burn is really a matter of weight, time, and distance. Heart rate really isn't a factor, except as a way to guess at VO2max, and even then, heart rate and VO2max don't even correlate all that well.

    Plus an HRM only works at all for steady state cardio. Once you add in changes in speed (sprints, intervals, etc.) or try and do different types of exercises (like weight lifting,) they become completely useless. It's why I've never bothered with one.
  • mitch16
    mitch16 Posts: 2,113 Member
    edited November 2014
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    Runner's World online has a calculator... I used this to validate what I get from my HRM for my runs:

    http://www.runnersworld.com/tools/calories-burned-calculator

    (And because of the error factor I never eat all of my calories back.)

  • DaFibble
    DaFibble Posts: 152 Member
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    Darn. If they only work for steady state cardio that's not so good for me because I like to mix it up. If I start to get tired doing stationary bike I jump off it and do some calisthenics for a few minutes before jumping back on. Helps me last longer in my exercise buzz zone.
  • tasch79
    tasch79 Posts: 17 Member
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    Well after doing the test on my hrm again to set the VO2max I went to the gym this afternoon and did the same run I previously did where my hrm said 620 calories. This time it said 413 calories (4.5km). I think that sounds fairly accurate.

    Interestingly I entered stats into some online calculators and got the following:
    • mapmyrun = 505 cals
    • coolrunning = 396 cals
    • runnersworld = 379 cals
    • healthstatus.com = 401 cals
    • caloriesburnedhq = 412 cals

    So yep a bit all over the place but I think I'm happy with my hrm calculation! Plus if I only eat back up to 50% of these cals, I think I'm in a good place.
  • blobby10
    blobby10 Posts: 357 Member
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    I run outside (x country) and tend to work on around 90 cals per mile running at 11minute mile max. If I run on the road at a 9.5minute mile I work on 100 cals per mile. It can only ever be a best estimate after all!

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