Feedback on Calculating the Burn

debrawallin
debrawallin Posts: 55 Member
in Fitness and Exercise
Which calculation would you trust to be more accurate: MFP, readout on gym machine or heart rate monitor (Body Media)? I have just used MFP but I notice it's different from the machine at the gym? Thanks for your feedback.

Replies

  • heybales
    heybales Posts: 18,842 Member
    Which calculation would you trust to be more accurate: MFP, readout on gym machine or heart rate monitor (Body Media)? I have just used MFP but I notice it's different from the machine at the gym? Thanks for your feedback.

    BodyMedia is NOT a HRM, and knows nothing of your intensity for anything beyond walking or jogging slow.

    But MFP, the machine, and Bodymedia for walking/slow jogging are all going to use standard calc's like this site below.

    Moving a known mass so fast for so much time up so much incline is pretty mathematical.

    The only difference is this site lets you see what NET burn is, how much burn over and above what your BMR would have burned anyway. MFP may or may not use GROSS or NET, might compare that and machine and see if you have written down some figures.

    http://www.exrx.net/Calculators/WalkRunMETs.html

    Depending on activity, walking is most accurate, with jogging your own abilities or inefficiencies start entering the picture, and therefore your HR as indicator of calories burned might change it a bit.

    But for treadmills or anything that knows the watts you just produced, the HR will just indicate if you were burning mostly carbs (hard effort) or fat (easier effort).
  • debrawallin
    debrawallin Posts: 55 Member
    Glad I asked. I think I get it a bit better now. I was on the elliptical and what was on the readout is different from MFP.
  • heybales
    heybales Posts: 18,842 Member
    Glad I asked. I think I get it a bit better now. I was on the elliptical and what was on the readout is different from MFP.

    Ah, elliptical.

    Now that is one where MFP has no idea of the intensity, or incline, tension, pace, ect. At least for treadmill, you enter speed, though incline totally changes the story too.

    If you input your weight, good chance it was pretty correct, because for the setting you used for tension (ie incline for treadmill), and the speed you went (pace for incline), it knows exactly how many watts you expended moving the footpads around.

    Watts is energy. Calories burned is energy.

    Sadly, the elliptical isn't likely to give you this info, perhaps it does though. What brand machine is it? I believe it was Life cycle that tested well for displaying correct info. Still the question if it's net or gross.

    http://www.exrx.net/Calculators/CycleMETs.html
  • Tilran
    Tilran Posts: 627 Member
    I find that the Polar series of HRMs are very good and tend to be accurate.
  • sotellmedarling
    sotellmedarling Posts: 35 Member
    All this talk of math and likely error make me wonder if I should even bother investing in a HRM (I would probably go with the Polar FT4 or FT7). If it's only a guess anyhow, should I just stick with MFPs calculations (or trim them down a bit when re-eating as a caution)?

    I've tried the many types of calculators, but I'm more than a little dimwitted when it comes to numbers (let alone finding my own pulse and checking it accurately).

    It's all very overwhelming. I love exercise, but want to be sure I can calculate it as accurately as possible. But I just don't know what to trust.
  • myfitnessnmhoy
    myfitnessnmhoy Posts: 2,105 Member
    Glad I asked. I think I get it a bit better now. I was on the elliptical and what was on the readout is different from MFP.

    I'd trust the elliptical readout a little more than MFP's, to a point.

    During the non-bicycling season, the elliptical is my go-to cardiomonster. It has a built-in heart rate monitor and I have verified the accuracy in its calculations based on the same formula any HRM uses.

    The key difference is that the elliptical knows how intensely I am working out - MFP does not. MFP's numbers seem to be based on using the elliptical at fairly high intensity (85% VO2, otherwise known as the "top of the cardio zone" on my elliptical).

    So basically in order to have MFP's numbers be accurate, I have to get on the elliptical, set the resistance to "running in treacle" and run like I'm being chased by rabid chainsaw-wielding weasels.

    Which, in my case, is exactly how I use the elliptical, so MFP's numbers tend to work out pretty well for me.
  • myfitnessnmhoy
    myfitnessnmhoy Posts: 2,105 Member
    All this talk of math and likely error make me wonder if I should even bother investing in a HRM (I would probably go with the Polar FT4 or FT7). If it's only a guess anyhow, should I just stick with MFPs calculations (or trim them down a bit when re-eating as a caution)?

    Certainly a heart rate monitor can't hurt, but I haven't invested in one and it hasn't been a problem.

    Take MFP's numbers as gospel to start with, unless you have a source of numbers like the readings off your elliptical. When using MFP's numbers, understand that whatever you get from them is going to be based on the highest intensity of that exercise, so if you pick "brisk walk" you better be power-walking and not window shopping. Only count the time you spend actually performing the exercise, and try to be honest with yourself as to how much time you actually spent doing meaningful exercise.

    Go with that for a few weeks, and see how you do. If you're losing weight at the pace you set, it's all good. If you aren't, think seriously about how you are feeling. If you're tired a lot, you might want to INCREASE the calorie burn you are counting for in your exercise and eat a little more. If you aren't losing weight and you are feeling energetic and really good, try lowering your calorie intake by a couple hundred calories a day and see what that does.

    You can estimate and calculate and buy gizmos and whatnot, or you can just go with the best numbers you have and see how they work out, then experiment from there.

    The nice thing about experimenting is that you are learning great lessons that will come in real handy when you go to maintenance, and also when you start hitting plateaus - because we all hit them, and the people who have played with their diet and focused on gaining experience as much as losing weight seem better equipped to handle them and take them in stride.
  • debrawallin
    debrawallin Posts: 55 Member
    Which calculation would you trust to be more accurate: MFP, readout on gym machine or heart rate monitor (Body Media)? I have just used MFP but I notice it's different from the machine at the gym? Thanks for your feedback.

    BodyMedia is NOT a HRM, and knows nothing of your intensity for anything beyond walking or jogging slow.

    But MFP, the machine, and Bodymedia for walking/slow jogging are all going to use standard calc's like this site below.

    Moving a known mass so fast for so much time up so much incline is pretty mathematical.

    The only difference is this site lets you see what NET burn is, how much burn over and above what your BMR would have burned anyway. MFP may or may not use GROSS or NET, might compare that and machine and see if you have written down some figures.

    http://www.exrx.net/Calculators/WalkRunMETs.html

    Depending on activity, walking is most accurate, with jogging your own abilities or inefficiencies start entering the picture, and therefore your HR as indicator of calories burned might change it a bit.

    But for treadmills or anything that knows the watts you just produced, the HR will just indicate if you were burning mostly carbs (hard effort) or fat (easier effort).


    It is a Precor at 24hour, I do the fat burner cycle, have to enter my weight and age and the resistance goes up and down on the program. I am pretty steady at 125 on the heart rate. It's shows 20 minutes to be a 271 burn.
  • debrawallin
    debrawallin Posts: 55 Member
    Glad I asked. I think I get it a bit better now. I was on the elliptical and what was on the readout is different from MFP.

    I'd trust the elliptical readout a little more than MFP's, to a point.

    During the non-bicycling season, the elliptical is my go-to cardiomonster. It has a built-in heart rate monitor and I have verified the accuracy in its calculations based on the same formula any HRM uses.

    The key difference is that the elliptical knows how intensely I am working out - MFP does not. MFP's numbers seem to be based on using the elliptical at fairly high intensity (85% VO2, otherwise known as the "top of the cardio zone" on my elliptical).

    So basically in order to have MFP's numbers be accurate, I have to get on the elliptical, set the resistance to "running in treacle" and run like I'm being chased by rabid chainsaw-wielding weasels.

    Which, in my case, is exactly how I use the elliptical, so MFP's numbers tend to work out pretty well for me.

    Thanks, good advice.
  • marijasmin
    marijasmin Posts: 160 Member
    Average them

    Jasmin
  • heybales
    heybales Posts: 18,842 Member
    It is a Precor at 24hour, I do the fat burner cycle, have to enter my weight and age and the resistance goes up and down on the program. I am pretty steady at 125 on the heart rate. It's shows 20 minutes to be a 271 burn.

    Excellent.

    Age is for the machine to set some rough HR zones for you to work out in. They don't even use HR in their calcs, because you may not be using HR function on the machine.

    Because whether you are old or young, if it felt easy or hard, if you weigh 180 lbs, and for 20 min push 150 watts with your legs, you burned about 190 calories of energy to generate that 150 watts.

    Also, if 20-30 min is your workout time, don't worry about fat-burning zone.
    Work out as hard as you are able.
    You'll burn just as many calories of fat working harder, but more calories overall. So of course the percentage of fat calories is lower therefore.
    But you just burned as many, and more calories.

    Now, you start going 30-60 min and try doing that everyday, you aren't allowing the body to recover well, because that is an extended hard workout. But you can do that for 20-30 min fine.

    Here is Precor's comments on the fact they do display MET's and watts.
    http://connect.precor.com/pdf/performance_metrics_ENGLISH.pdf
  • debrawallin
    debrawallin Posts: 55 Member
    During the week I go on lunch hours so I can only get 20 to 25 minutes in on a work out. I could come in a little earlier so that my time could equal out. I'l try programming the manual with weight and age and go as fast as I can and see if that makes more of a burn. I am 56 and weigh 238, should I shoot for a higher heart rate than 125?
  • Vic_of_Steel
    Vic_of_Steel Posts: 570 Member
    I was just going by what MFP said and the numbers were pretty high. So I decided to get a HRM. It has probably been one of the best investments ever for two main reasons.

    1. It motivates me to see where I am and where I need to be and also how many calories I am burning.
    2. The calories are being based off of what your heart rate is not some calculator that tells you what your suppose to be burning.

    When I compared the two (HRM & MFP) depending on my intensity MFP showed almost double what I was showing on my heart rate. I love seeing the numbers on MFP but I would so much rather it be below what I am burning vs over. I would invest in a heart rate monitor if it is a big deal especially if you plan on eating your work out calories back. The actual machine was a lot closer but still higher because I wasn't always holding onto the grips that record my heart rate. I have a polar FT7 it is awesome and wasn't expensive.
  • heybales
    heybales Posts: 18,842 Member
    During the week I go on lunch hours so I can only get 20 to 25 minutes in on a work out. I could come in a little earlier so that my time could equal out. I'l try programming the manual with weight and age and go as fast as I can and see if that makes more of a burn. I am 56 and weigh 238, should I shoot for a higher heart rate than 125?

    If you've been exercising for more than 2 weeks at that level, with no problems, you can a week at a time and kick it up 5 bpm. At some point your cardio system hasn't improved enough to keep going up, and then you'll be at that level for a bit.

    Bumping the incline or tension ever so slightly should allow you to nail it.
  • debrawallin
    debrawallin Posts: 55 Member
    Which calculation would you trust to be more accurate: MFP, readout on gym machine or heart rate monitor (Body Media)? I have just used MFP but I notice it's different from the machine at the gym? Thanks for your feedback.

    BodyMedia is NOT a HRM, and knows nothing of your intensity for anything beyond walking or jogging slow.

    But MFP, the machine, and Bodymedia for walking/slow jogging are all going to use standard calc's like this site below.

    Moving a known mass so fast for so much time up so much incline is pretty mathematical.

    The only difference is this site lets you see what NET burn is, how much burn over and above what your BMR would have burned anyway. MFP may or may not use GROSS or NET, might compare that and machine and see if you have written down some figures.

    http://www.exrx.net/Calculators/WalkRunMETs.html

    Depending on activity, walking is most accurate, with jogging your own abilities or inefficiencies start entering the picture, and therefore your HR as indicator of calories burned might change it a bit.

    But for treadmills or anything that knows the watts you just produced, the HR will just indicate if you were burning mostly carbs (hard effort) or fat (easier effort).

    I finally figured out about the MET's, the Body Media give me the daily average on the MET's. When I do the elliptical, it is 1.1 so I am going to work on betting my MET's up. This is like getting a whole new education. :)

Categories