Does MFP really overestimate exercise calories burned?

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  • ScubaSteve1962
    ScubaSteve1962 Posts: 609 Member
    edited October 2015
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    I've used several elliptical machines, so I do follow my activity monitor blindly, that's the one thing that I know is constant. Don't have to worry about calibration or anything else. And hopefully my Vo2 is correct which makes it even more accurate than the machines. MFP estimates are more than any machine I've ever been on. I was just trying to show the OP the difference between the 2
    Yes, after 65 mins of elliptic training the machine max showed 500 cals burned, and that's if I push myself way too hard. MFP on the other hand shows around 700-800 calories for the same level of exercise. I enter what the machine says, not the app.

    But you don't know which is more accurate unless you monitor food, exercise and weight loss. You just artificially picked the lower one because you wanted to.

    Same with ScoobaSteve, does he really know that his activity tracker is more accurate, or is he blindly following it? Activity trackers are still doing estimations after all (granted, if I had to choose blindly I'd choose the activity tracker over MFP).

    Again, it will vary per person and how they choose to log the activity in MFP (which can make a big difference too).



  • MeanderingMammal
    MeanderingMammal Posts: 7,866 Member
    edited October 2015
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    Ponkeen wrote: »
    Just wondering, as I have seen this mentioned in the threads. Has anyone reading actually put this to the test against another tracker? I would rather hear from those who have in fact put it to the test, or see a link to a reliable study, than hear people repeating what they have also read from other people in the forums here. Verifiable is preferred- how does one know for sure how reliable, or not, the exercise calorie tracking is?

    A lot depends on what kind of training that you do, for some things it's pretty reliable, for others it's very dependent on self reporting of actual exertion, so it can be a bit hit and miss.

    I've done some comparative work for running, road cycling, mountain biking and walking.

    I've used both Polar and Garmin HRMs, Runkeeper, Strava, Endomondo, Runtastic and MF assessments to get some idea. I've generally found MFP to be in the middle of the distribution curve with Endomondo being least conservative and Strava being most conservative. That's been on both Apple and Android phones. I also calculated manually.

    In principle you could assess that the discrepancy is based on different apps taking different data inputs, but

    I've also got access to a wide range of simulators, so taking a common data feed, from my Garmin, I an take the data through a pretty wide range of different approximation algorithms. Again a spread of results, although slightly narrower than the preceding.

    What I'd observe is that the spread of results was reasonably narrow for running and road cycling, about 300 cals between highest and lowest for a 10 mile run burning about 1000cals, and a similar ride consuming about 1000cals. Spread for mountain biking was pretty broad, aout 600cals, but that's understandable and my Polar was by far the highest by about 400 cals from the paper calculation. For walking it was again a broad spread, again HR being highest, but that's very much because walking isn't an appropriate exercise to approximate using HR.

    There are lots of things where there is no reliable way o estimate calorie expenditure, so it's near impossible to say whether it's overinflating actual effort or reported effort.

    fwiw I'm a control engineer by training, hence having access to the simulators that most people aren't going to be able to get hold of.
  • Stoshew71
    Stoshew71 Posts: 6,553 Member
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    MobyCarp wrote: »
    I see the estimation factor with the calorie burn numbers generated by Garmin. When I don't wear the heart rate monitor, or the battery dies, Garmin produces higher calories burned than for similar runs when I do wear the monitor. I think I'm in pretty good cardio shape; someone else could see a difference in the opposite direction.

    All calorie burn numbers are estimates, and the economic incentive for equipment makers is to overestimate the burn. That's why the common advice is not to eat back all the calories; they aren't all real.

    That having been said, the base metabolic rate is also an estimate. It can be too high or too low for any given individual. Sometimes I think that most success stories are produced by people who (like myself) burn more calories than the canned estimates say they do, and that many of the "I can't lose weight" stories come from people who burn fewer calories than the canned estimates say they do.

    jemhh wrote: »
    I think these are really good points and observations. People would be well served by starting with the stock numbers and then adjust based on what actually happens when they follow them. And by follow them I mean actually eat to that level, not eat under it "just to be safe."
    Yes, after 65 mins of elliptic training the machine max showed 500 cals burned, and that's if I push myself way too hard. MFP on the other hand shows around 700-800 calories for the same level of exercise. I enter what the machine says, not the app.

    But you don't know which is more accurate unless you monitor food, exercise and weight loss. You just artificially picked the lower one because you wanted to.

    Same with ScoobaSteve, does he really know that his activity tracker is more accurate, or is he blindly following it? Activity trackers are still doing estimations after all (granted, if I had to choose blindly I'd choose the activity tracker over MFP).

    Again, it will vary per person and how they choose to log the activity in MFP (which can make a big difference too).

    These 3 quotes pretty much sums it all up.
  • Jruzer
    Jruzer Posts: 3,501 Member
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    lemurcat12 wrote: »
    I think it's accurate for some things, not for others, and it varies person by person.
    The only problem is that it doesn't deduct out how many calories you would have burnt anyway (neither do most apps or HRMs), which doesn't make much difference for a shorter run, but will throw off the calories quite a bit for a long run.
    ...
    Many people perceive themselves as exercising intensely (because it is for them, they are out of shape) when it's not that intense in terms of what's meant, and so end up with an overstated exercise burn. I think that's why the elliptical (which presumes intense) often seems to be one of the worst offenders.

    Big thumbs up for these two statements. I always subtract 2 kcal/min from every exercise I do to account for resting energy expenditure, and I never put the elliptical on intense - always moderate - even if I feel like I killed it.
  • MeanderingMammal
    MeanderingMammal Posts: 7,866 Member
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    lemurcat12 wrote: »
    I think that's why the elliptical (which presumes intense) often seems to be one of the worst offenders.

    The MET value for moderate Elliptical is the same as the MET for walking at an average pae on a level, hard surface. Lots of people seem to assume somewhat more effectiveness.

  • Jruzer
    Jruzer Posts: 3,501 Member
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    lemurcat12 wrote: »
    I think that's why the elliptical (which presumes intense) often seems to be one of the worst offenders.

    The MET value for moderate Elliptical is the same as the MET for walking at an average pae on a level, hard surface. Lots of people seem to assume somewhat more effectiveness.

    Interesting. I hadn't heard that before. I typically get ~ 9 kcal/min net from the elliptical and 5 kcal/min net from walking.
  • FGTisme
    FGTisme Posts: 87 Member
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    My heart rate monitor will show around 425-450 per hour on my ski machine. I have verified that with estimates calculated on pulse rate / my weight, etc.

    MFP estimates it at 580. That's 900 calories every week that I would be over eating! It is definitely off with that exercise. MFP was also high in estimating walking calories.
  • bwogilvie
    bwogilvie Posts: 2,130 Member
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    In my experience, for cycling MFP estimates 50-80% more calories than my Garmin Edge 800 estimates. The Edge takes into account my weight, my bicycle's weight, the terrain (up, down, or flat), my speed (because the power required to overcome wind resistance is proportional to the cube of the speed), my activity level (which I programmed in), and my maximum and resting heart rates. Its estimates match my actual weight loss pretty well, so I trust it.

    My Garmin Forerunner 620 estimates I burn about 104-105 calories per mile running on flat ground at a pace of 7:30-8:00/mile. MFP estimates about 110. Not a huge difference, but it can add up over the course of a week.

    In other words, I would eat way too many calories if I trusted MFP for cycling burns, and a little too much if I trusted it for running.
  • kcjchang
    kcjchang Posts: 709 Member
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    MFP is overestimating by a factor of 40% for me. I log the results of my bicycle rides based on power recording from my power meter (closest one can get other than actual laboratory testing although some may frit about left only, left/right, and branding); however, I have not paid for laboratory testing to determine my calories efficiency and arbitrarily set that 25%. I'm probably closer to 22-23% which would raise the overestimation closer to 50%. I use virtual power (VP) to estimate calories from my walks (2.3 miles route, flat, and my pace is usually around 4-4.3mph) and they are roughly equal to MFP's estimates. I get more spikes and valleys with VP (probably due to GPS error) but it evens out on the long run. I have no ideal how accurate the VP is but the underlying equation used matches very well to the MFP's empirical extract at the intensity that I walk. The VP, the underlying equation, is really meant for running so I can't imagine both are based on the same empirical formula (which makes sense since the app's VP for cycling is based on fundamental physics). The app is call IpBike.
  • sijomial
    sijomial Posts: 19,811 Member
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    bwogilvie wrote: »
    In my experience, for cycling MFP estimates 50-80% more calories than my Garmin Edge 800 estimates. The Edge takes into account my weight, my bicycle's weight, the terrain (up, down, or flat), my speed (because the power required to overcome wind resistance is proportional to the cube of the speed), my activity level (which I programmed in), and my maximum and resting heart rates. Its estimates match my actual weight loss pretty well, so I trust it.

    My Garmin Forerunner 620 estimates I burn about 104-105 calories per mile running on flat ground at a pace of 7:30-8:00/mile. MFP estimates about 110. Not a huge difference, but it can add up over the course of a week.

    In other words, I would eat way too many calories if I trusted MFP for cycling burns, and a little too much if I trusted it for running.

    I also use a Garmin Edge 800 and find it significantly under estimates calories (10 - 20%) when compared to a power meter and a custom calibrated HRM.
    Power meter and the HRM are just about identical when used under very controlled steady state riding, as soon as I get too hot they diverge very quickly. Ditto for intervals of course.

    MFP's 14-16mph estimate is pretty reasonable but I find the spread in the 16-20mph far too wide, there's an enormous difference in real life between 16 and 20mph.

    Everything is an estimate.......
  • robertw486
    robertw486 Posts: 2,390 Member
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    Ponkeen wrote: »
    Just wondering, as I have seen this mentioned in the threads. Has anyone reading actually put this to the test against another tracker? I would rather hear from those who have in fact put it to the test, or see a link to a reliable study, than hear people repeating what they have also read from other people in the forums here. Verifiable is preferred- how does one know for sure how reliable, or not, the exercise calorie tracking is?

    A lot depends on what kind of training that you do, for some things it's pretty reliable, for others it's very dependent on self reporting of actual exertion, so it can be a bit hit and miss.

    I've done some comparative work for running, road cycling, mountain biking and walking.

    I've used both Polar and Garmin HRMs, Runkeeper, Strava, Endomondo, Runtastic and MF assessments to get some idea. I've generally found MFP to be in the middle of the distribution curve with Endomondo being least conservative and Strava being most conservative. That's been on both Apple and Android phones. I also calculated manually.

    In principle you could assess that the discrepancy is based on different apps taking different data inputs, but

    I've also got access to a wide range of simulators, so taking a common data feed, from my Garmin, I an take the data through a pretty wide range of different approximation algorithms. Again a spread of results, although slightly narrower than the preceding.

    What I'd observe is that the spread of results was reasonably narrow for running and road cycling, about 300 cals between highest and lowest for a 10 mile run burning about 1000cals, and a similar ride consuming about 1000cals. Spread for mountain biking was pretty broad, aout 600cals, but that's understandable and my Polar was by far the highest by about 400 cals from the paper calculation. For walking it was again a broad spread, again HR being highest, but that's very much because walking isn't an appropriate exercise to approximate using HR.

    There are lots of things where there is no reliable way o estimate calorie expenditure, so it's near impossible to say whether it's overinflating actual effort or reported effort.

    fwiw I'm a control engineer by training, hence having access to the simulators that most people aren't going to be able to get hold of.

    I've found that between Endomondo and Strava, they are both very good at calories expended biking. However, Endomondo reports gross and grossly overestimates my BMR. With that taken out of the equation, both seem really close in net calorie burn. I did a lot of math to figure out if they were even ballpark!

    Endomondo reports I burn 139 calories per hour if I don't move. For a guy less than 200 pounds. Yes really.




    Lot's of great information being shared here, and it seems many of us just want to get the real calorie burn a little close to reality. I'd rather not have an app or program that does the math for me if the math is wrong. I understand nothing is perfect, but the variations can be huge.
  • kcjchang
    kcjchang Posts: 709 Member
    edited October 2015
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    Ops, lower calories efficiency increase calories expended. Got a chance to run the calc and was too high on original post.
    kcjchang wrote: »
    MFP is overestimating by a factor of 29% 40% for me. I log the results of my bicycle rides based on power recording from my power meter (closest one can get other than actual laboratory testing although some may frit about left only, left/right, and branding); however, I have not paid for laboratory testing to determine my calories efficiency and arbitrarily set that 25%. I'm probably closer to 22-23% which would lower raise the overestimation closer to 16-21% 50%. I use virtual power (VP) to estimate calories from my walks (2.3 miles route, flat, and my pace is usually around 4-4.3mph) and they are roughly equal to MFP's estimates. I get more spikes and valleys with VP (probably due to GPS error) but it evens out on the long run. I have no ideal how accurate the VP is but the underlying equation used matches very well to the MFP's empirical extract at the intensity that I walk. The VP, the underlying equation, is really meant for running so I can't imagine both are based on the same empirical formula (which makes sense since the app's VP for cycling is based on fundamental physics). The app is call IpBike.

    Here is the stats from my afternoon ride:

    Time Riding: 1:53:45
    Distance (miles): 35.84
    Work (kJ): 1330
    Average Speed (mph): 18.9
    Calories @25%: 1272 (+29% different from MFP)
    Calories @23%: 1382 (+21% different from MFP)
    Calories @22%: 1445 (+16% different from MFP)
    MFP: 1655

    Checked a few other rides with different duration but similar average speed (18-20) and percentages stayed petty consistent for "Bicycling, 16-20 mph, very fast (cycling, biking, bike riding)". Haven't checked my rides where the average speeds are higher but expect something similar. Sorry, don't have anything slower.
  • MeanderingMammal
    MeanderingMammal Posts: 7,866 Member
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    robertw486 wrote: »
    Lot's of great information being shared here, and it seems many of us just want to get the real calorie burn a little close to reality. I'd rather not have an app or program that does the math for me if the math is wrong. I understand nothing is perfect, but the variations can be huge.

    I think the snag is that for most activities there are so many areas of uncertainty that it's near impossible to have a consistent method.

    Running is pretty straightforward, although elevation and surface make a difference. I'll burn far more trail running than road running for example. Cycling is affected by wind resistance that varies according to speed, posture on the bike, mechanical condition, tyre pressure etc.

    As soon as you get into self reporting on the Kolb scale you're into the judgement that lemurcat identifies. Does the level of effort that means 5 for me mean the same as 5 for you, or 5 for my partner, who happens to be disabled?
  • MeanderingMammal
    MeanderingMammal Posts: 7,866 Member
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    Jruzer wrote: »
    lemurcat12 wrote: »
    I think that's why the elliptical (which presumes intense) often seems to be one of the worst offenders.

    The MET value for moderate Elliptical is the same as the MET for walking at an average pae on a level, hard surface. Lots of people seem to assume somewhat more effectiveness.

    Interesting. I hadn't heard that before. I typically get ~ 9 kcal/min net from the elliptical and 5 kcal/min net from walking.

    On the 2011 release of the research both of those have a MET factor of 5. That is for walking at 4mph, which is a comfortable pace.
  • ScubaSteve1962
    ScubaSteve1962 Posts: 609 Member
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    Ponkeen wrote: »
    Just wondering, as I have seen this mentioned in the threads. Has anyone reading actually put this to the test against another tracker? I would rather hear from those who have in fact put it to the test, or see a link to a reliable study, than hear people repeating what they have also read from other people in the forums here. Verifiable is preferred- how does one know for sure how reliable, or not, the exercise calorie tracking is?

    A lot depends on what kind of training that you do, for some things it's pretty reliable, for others it's very dependent on self reporting of actual exertion, so it can be a bit hit and miss.

    I've done some comparative work for running, road cycling, mountain biking and walking.

    I've used both Polar and Garmin HRMs, Runkeeper, Strava, Endomondo, Runtastic and MF assessments to get some idea. I've generally found MFP to be in the middle of the distribution curve with Endomondo being least conservative and Strava being most conservative. That's been on both Apple and Android phones. I also calculated manually.

    In principle you could assess that the discrepancy is based on different apps taking different data inputs, but

    I've also got access to a wide range of simulators, so taking a common data feed, from my Garmin, I an take the data through a pretty wide range of different approximation algorithms. Again a spread of results, although slightly narrower than the preceding.

    What I'd observe is that the spread of results was reasonably narrow for running and road cycling, about 300 cals between highest and lowest for a 10 mile run burning about 1000cals, and a similar ride consuming about 1000cals. Spread for mountain biking was pretty broad, aout 600cals, but that's understandable and my Polar was by far the highest by about 400 cals from the paper calculation. For walking it was again a broad spread, again HR being highest, but that's very much because walking isn't an appropriate exercise to approximate using HR.

    There are lots of things where there is no reliable way o estimate calorie expenditure, so it's near impossible to say whether it's overinflating actual effort or reported effort.

    fwiw I'm a control engineer by training, hence having access to the simulators that most people aren't going to be able to get hold of.

    an engineer, ahhh so that explains alot (LOL)

  • RobynLB83
    RobynLB83 Posts: 626 Member
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    Jruzer wrote: »
    lemurcat12 wrote: »
    I think that's why the elliptical (which presumes intense) often seems to be one of the worst offenders.

    The MET value for moderate Elliptical is the same as the MET for walking at an average pae on a level, hard surface. Lots of people seem to assume somewhat more effectiveness.

    Interesting. I hadn't heard that before. I typically get ~ 9 kcal/min net from the elliptical and 5 kcal/min net from walking.

    On the 2011 release of the research both of those have a MET factor of 5. That is for walking at 4mph, which is a comfortable pace.

    I am a climber, boxer, runner, and avid hiker, and I can attest that walking 4mph is not a comfortable pace, and not even a pace that many people can hold for a mile.
  • RobynLB83
    RobynLB83 Posts: 626 Member
    edited October 2015
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    RobynLB83 wrote: »
    Jruzer wrote: »
    lemurcat12 wrote: »
    I think that's why the elliptical (which presumes intense) often seems to be one of the worst offenders.

    The MET value for moderate Elliptical is the same as the MET for walking at an average pae on a level, hard surface. Lots of people seem to assume somewhat more
  • robertw486
    robertw486 Posts: 2,390 Member
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    Ponkeen wrote: »
    Thanks oilphins! That is what I was looking for- an actual test of some sort. The other feedback is helpful, too. I intentionally underestimate the amount of time I spend exercising in order to control for little breather moments, waiting at intersections, etc... I just wasn't sure beyond that if I could trust the count.

    I have two apps that report to MFP, Endomondo and Strava. So when I do my bike rides, they total calories and report to MFP. No matter how MFP classifies them, the calorie count remains whatever the app recorded. Through some personal testing and comparisons with known to be accepted biking calculators, I have found that both apps are fairly accurate in measuring calorie burn while riding. However, I have found that Endomondo reports gross calories burned, including BMR, and also grossly overestimates my BMR. Strava reports only calories actually burned above what I would burn at rest, so it will now be the app I used for all biking.

    For my elliptical miles, I use the calculated calories shown on the elliptical and enter them into MFP. Since the elliptical we have uses inputs such as weight, age, heart rate, ramp, and resistance in the calculation it should be much more accurate than any assigned value per minute an app would assign. I haven't yet done as much work on calculating vs known good formulas, but the elliptical is simply not the same as walking so it's a harder comparison.



    Since several of you are actually using power meters when biking, I personally think the main issue would be software integration. Assuming the power meter is accurate, it really doesn't matter what the terrain, incline, aero profile, rolling resistance, etc are. Power to the pedals should be king regardless in terms of human output. The HRM integration might be useful to somehow compare power output to heart rate to help an app calculate some of the variables mentioned above, but since we know HRMs only work well under certain conditions it would be of little other use IMO.


    Jruzer wrote: »
    lemurcat12 wrote: »
    I think that's why the elliptical (which presumes intense) often seems to be one of the worst offenders.

    The MET value for moderate Elliptical is the same as the MET for walking at an average pae on a level, hard surface. Lots of people seem to assume somewhat more effectiveness.

    Interesting. I hadn't heard that before. I typically get ~ 9 kcal/min net from the elliptical and 5 kcal/min net from walking.

    On the 2011 release of the research both of those have a MET factor of 5. That is for walking at 4mph, which is a comfortable pace.

    But an elliptical isn't the same as walking. On our elliptical (an older Precor) even with the ramp at the lowest setting, the stride movement is somewhat "uphill" if you will, and the amount you have to lift your foot in the forward step is dictated my the mechanics of the machine. Combine that with the variable resistance, and the calorie burn can be changed quite a lot with those two adjustments that the machine allows. As an example, on our machine with the ramp steep and resistance up, it's more similar to walking up stairs. Thus you can go at a slower pace and burn equal calories, or go at the same pace and burn more calories.

    Today I got on our elliptical and did some testing of my HRM on the bike computer vs the HRM on the machine. In steady state mode without working very hard I was showing 7-7.2 METS/10-10.5 calories per minute. This was with minimal ramp and resistance at around 10 IIRC. Bumping resistance and ramp up more I got to 10 METS/15 calories per minute range. Both of those readings were at a cadence of right around 4.8 MPH as measured on the machine. But at any rate, if you allow variance for all the factors that can change, I don't see how any app without those inputs could be anything other than a complete SWAG. And more than likely they use some kind of average.

    I also did some testing on the machine HRM vs a chest strap HRM, which was my original goal. The machine and the chest strap report virtually the same heart rate, and the machine does in fact use heart rate in applying weight to calories burned per minute. During warm up my calories per minute reading was lower until my heart rate came up and stabilized, while remaining at a steady pace/ramp/resistance.
  • robertw486
    robertw486 Posts: 2,390 Member
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    RobynLB83 wrote: »

    I am a climber, boxer, runner, and avid hiker, and I can attest that walking 4mph is not a comfortable pace, and not even a pace that many people can hold for a mile.

    I think this is more a subjective thing. If someone rarely walks and has a short stride it's a tougher task. For more long legged people that are thin, more fit, or just walk more and condition those muscles it's much easier.

    What's "comfortable" is the big question that is so subjective to me. That all depends on fitness levels, body shape and weight, as well as the when and where of the walking. But personally I think other than some shorter or heavier people, many if not most people can walk a 4 mph pace for a mile.

  • MeanderingMammal
    MeanderingMammal Posts: 7,866 Member
    edited October 2015
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    RobynLB83 wrote: »
    Jruzer wrote: »
    lemurcat12 wrote: »
    I think that's why the elliptical (which presumes intense) often seems to be one of the worst offenders.

    The MET value for moderate Elliptical is the same as the MET for walking at an average pae on a level, hard surface. Lots of people seem to assume somewhat more effectiveness.

    Interesting. I hadn't heard that before. I typically get ~ 9 kcal/min net from the elliptical and 5 kcal/min net from walking.

    On the 2011 release of the research both of those have a MET factor of 5. That is for walking at 4mph, which is a comfortable pace.

    I am a climber, boxer, runner, and avid hiker, and I can attest that walking 4mph is not a comfortable pace, and not even a pace that many people can hold for a mile.

    4mph across rough terrain, carrying a daysac and fighting order is a standard planning assumption. That's comfortable, and sustainable. It's the rate I'd expect an able bodied individual to be able to walk on flatter terrain and without a load.

    It's only a 15 minute mile.

    Personally I walk a bit faster than that, so find slowing down to walk with others a bit uncomfortable.