Strava vs myfitnesspal - walking calories burned

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torvallis
torvallis Posts: 8 Member
in Fitness and Exercise
I walked for 36 minutes. Strava enters the 36 minutes at 4.0 mph and that I burned 546 calories. If I enter 36 minutes at 4.0 mph manually, myfitnesspal says I burned 323 calories. Why the discrepancy? Should I just be entering the information in manually?

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  • Mr_Knight
    Mr_Knight Posts: 9,532 Member
    edited April 2015
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    calories burned walking = weight in pounds * miles walked * 0.3

    Both numbers look like big over-estimates. Take the lower one and cut it in half, at least you'll be somewhat close then.
  • OldHobo
    OldHobo Posts: 647 Member
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    torvallis wrote: »
    I walked for 36 minutes. Strava enters the 36 minutes at 4.0 mph and that I burned 546 calories. If I enter 36 minutes at 4.0 mph manually, myfitnesspal says I burned 323 calories. Why the discrepancy? Should I just be entering the information in manually?
    I've never heard of Strava but google says it's based on GPS. Is it possible that Strava is taking topography into account. Are there hills involved?
    Mr_Knight wrote: »
    calories burned walking = weight in pounds * miles walked * 0.3
    ...
    Mr. Knight. Could your formula be missing a factor? It doesn't seem to take speed into account. I weigh 255 and MFP credits 204 calories burned in 32 minutes at 3.0 mph.
    255 * 1.6 * .3 = 122.4.
    What am I missing?

  • heybales
    heybales Posts: 18,842 Member
    edited April 2015
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    Walking has a rough calorie burn per mile.
    The pace/speed merely determines how many miles you do in your available time.

    Though in reality, pace does make a difference if you were to do a great amount of it.
    And I do notice the midline 3.5 mph is actually a factor of 0.5 from those studies.

    http://www.exrx.net/Aerobic/WalkCalExp.html

    Running is much more flat line, so rough estimate isn't as rough.

    And yes, hills do count big time, up and down, and Strava does include hills in estimate of effort.
  • torvallis
    torvallis Posts: 8 Member
    edited April 2015
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    Mr_Knight wrote: »
    calories burned walking = weight in pounds * miles walked * 0.3

    Using that would make it 192. This is much lower than all of the walking calculators I've tried online. Are they all really overstating? Each one gives different results but all are in the MFP/Strava range though closer to MFP.

    OldHobo wrote: »
    Are there hills involved?

    Nothing you'd notice really.

    heybales wrote: »
    http://www.exrx.net/Aerobic/WalkCalExp.html

    So using this formula, calories burned is only 154, by far the lowest.

    Really don't know what to use now.

  • heybales
    heybales Posts: 18,842 Member
    edited April 2015
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    You noticed that was calorie burn per mile per 100 lbs, right?

    Almost double the 0.3 figure in that other formula from I'm not sure where, if you divide out the 100 lbs to make it equal formula.

    Your 4 mph becomes weight x miles x 0.58 = calories.
  • torvallis
    torvallis Posts: 8 Member
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    Ok, senior moment. Using tonight's walk of 2.69 miles at 4.48 mph would be 65*2.69*2.37=414. Correct?
  • LKArgh
    LKArgh Posts: 5,179 Member
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    You are not burning anything close to these numbers by walking for half an hour. Unless you are very obese, like 400 lbs, you are not burning 400 calories in half an hour by walking.
  • LKArgh
    LKArgh Posts: 5,179 Member
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    torvallis wrote: »
    Ok, senior moment. Using tonight's walk of 2.69 miles at 4.48 mph would be 65*2.69*2.37=414. Correct?
    What are these numbers? Are you sure you are not mixing up your units? Like kilos/pounds, miles/km?
  • heybales
    heybales Posts: 18,842 Member
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    Ya, gotta look at what that chart is based on, and you have too many variables.

    So using the 3.5 mph value as example.

    weight in lbs x distance in miles x 0.5 = calories burned per workout.

    Just take whatever that chart says for the pace you went, divide by 100, and use that value in the above formula.
    If you have only 2 paces you go, just get those values.

    Or click the link down the page for the actual walk/run calc based on those studies. It does all the math for you, though you still need to know pace.
    Use the Gross option to compare to Strava or HRM or database entry.
    Use the Net option to log and actually eat back.
  • Mr_Knight
    Mr_Knight Posts: 9,532 Member
    edited April 2015
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    OldHobo wrote: »
    Mr_Knight wrote: »
    calories burned walking = weight in pounds * miles walked * 0.3
    ...
    Mr. Knight. Could your formula be missing a factor? It doesn't seem to take speed into account. I weigh 255 and MFP credits 204 calories burned in 32 minutes at 3.0 mph.
    255 * 1.6 * .3 = 122.4.
    What am I missing?

    Speed * time = distance.

    120 calories for your examplew is about right.
  • Mr_Knight
    Mr_Knight Posts: 9,532 Member
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    torvallis wrote: »
    Mr_Knight wrote: »
    calories burned walking = weight in pounds * miles walked * 0.3

    Using that would make it 192. This is much lower than all of the walking calculators I've tried online. Are they all really overstating?

    Yep.

  • torvallis
    torvallis Posts: 8 Member
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    heybales wrote: »
    Ya, gotta look at what that chart is based on, and you have too many variables.
    ...
    Or click the link down the page for the actual walk/run calc based on those studies. It does all the math for you, though you still need to know pace.
    Use the Gross option to compare to Strava or HRM or database entry.
    Use the Net option to log and actually eat back.

    No, I don't have too many variables. I used the formula with the chart and got 414 calories and using the calculator linked to at the bottom of the page I get 415 calories. That would be using gross energy. 347 calories using net. MFP tells me 407 calories which I suppose is close enough because I don't eat them back.

  • heybales
    heybales Posts: 18,842 Member
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    Interesting study. I'll trust the online calc's.

    http://www.ncbi.nlm.nih.gov/pubmed/15570150

    (4.2 kJ is 1 calorie. Notice the energy expenditure on treadmill and track is almost equal.)

    That test Walking was 3.2 mph level for 1 mile for 19 min, calculation was 3.4 calories higher than tested 81 cal, or 4.2% higher.
    Running at 6.3 mph level for 1 mile for 9.5 min, calculation was 4.8 calories lower than tested 115 cal, or 4.2% lower.
  • SFDonovan
    SFDonovan Posts: 72 Member
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    Mr_Knight wrote: »
    torvallis wrote: »
    Mr_Knight wrote: »
    calories burned walking = weight in pounds * miles walked * 0.3

    Using that would make it 192. This is much lower than all of the walking calculators I've tried online. Are they all really overstating?

    Yep.

    I'm not so sure. I used my Polar FT4 with a chest strap on a 2.5 mile walk in 47 minutes. My pace was 3.2 The Polar says I burned 344.

    A 4.0 pace is much higher even though it was only 36 minutes. 323 could be right on the money. The Strava does seem high.
  • Mr_Knight
    Mr_Knight Posts: 9,532 Member
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    SFDonovan wrote: »
    Mr_Knight wrote: »
    torvallis wrote: »
    Mr_Knight wrote: »
    calories burned walking = weight in pounds * miles walked * 0.3

    Using that would make it 192. This is much lower than all of the walking calculators I've tried online. Are they all really overstating?

    Yep.

    I'm not so sure. I used my Polar FT4 with a chest strap on a 2.5 mile walk in 47 minutes. My pace was 3.2 The Polar says I burned 344.

    A 4.0 pace is much higher even though it was only 36 minutes. 323 could be right on the money. The Strava does seem high.

    Can't use an HRM for walking calories. It will over-estimate, the models aren't designed for low intensity activities.
  • torvallis
    torvallis Posts: 8 Member
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    Why would the intensity level matter to the monitor?
  • Mr_Knight
    Mr_Knight Posts: 9,532 Member
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    torvallis wrote: »
    Why would the intensity level matter to the monitor?

    Because heart rate and calories only correlate (somewhat) well under specific conditions.

    These devices don't exist because they work well - they exist because we know how to build them. Heart rate is really a pretty poor tool for guessing at energy expenditure.
  • heybales
    heybales Posts: 18,842 Member
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    The closer your HR was to 90, the more the inaccuracy, as that has been found to be the average point at which HR starts to be a flat line correlation to calorie burn up until you go anaerobic, which is also the point where inaccuracy starts to occur. So straight line, but with some curves at either end.

    Now if you kept hills going the entire time, maybe you did go fast enough.
    Eventually you'll get to point where flat walking 4mph is barely hitting 90.
  • TeaBea
    TeaBea Posts: 14,517 Member
    edited April 2015
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    torvallis wrote: »
    I walked for 36 minutes. Strava enters the 36 minutes at 4.0 mph and that I burned 546 calories. If I enter 36 minutes at 4.0 mph manually, myfitnesspal says I burned 323 calories. Why the discrepancy? Should I just be entering the information in manually?


    Sounds really high.....check out some different calculators so you can get a number you are comfortable with.

    Here's a calculator by weight, speed etc
    http://www.shapesense.com/fitness-exercise/calculators/walking-calorie-burn-calculator.aspx

    Here's a chart by your weight & walking speed
    http://walking.about.com/cs/howtoloseweight/a/howcalburn.htm
  • torvallis
    torvallis Posts: 8 Member
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    heybales wrote: »
    The closer your HR was to 90...
    Eventually you'll get to point where flat walking 4mph is barely hitting 90.

    Last night, at 4.48 mph the average heart rate was 123 and the max was 131. The monitor said 436 calories, MFP was 323, Strava was 559, and the website you linked to was 413/345. Seems best just to go with MFP.

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