Gym machine calories versus hrm calories

mucirl
mucirl Posts: 17 Member
I checked out my calorie burn on the cross trainer last night.
On both the wahoo hrm app and on the gym machine my heart rate was the same +- 2-4 heart beats
I did 60 minutes interval training 2 minutes level 7 and 1 min level 18 and my heart hart averaged 147 and peaked at 173.

The gym machine claimed I burned 800 calories ( I have been using this number until now) and the hrm claimed I burned 511.
How can there be such a difference ?
My t-shirt was dripping I was out of breath for the level 18 .

I am a bit of a data freek and I would just really like to know what my accurate cal burn is.

Thanks

Replies

  • EuroDivas
    EuroDivas Posts: 93 Member
    I am also waiting to hear. Good point for not eating all calories back..lol
  • hermann341
    hermann341 Posts: 443 Member
    Do the machine or the HRM have your height/weight/age data entered? The default weight setting is typically 150.
  • MinnieInMaine
    MinnieInMaine Posts: 6,400 Member
    My question is similar to hermann's - how much data do you enter into the cross trainer? Some machines ask for age, weight, but most don't ask for gender or height so how could it accurately calculate calories? Your HRM probably has all your personal stats and the more data, the more accurate the calculation.

    So I'd guess the 511 is more accurate.

    Curious - you said yo've been logging it as 800 calories all along - have you been eating all those calories back?
  • 3dogsrunning
    3dogsrunning Posts: 27,167 Member
    Just because the cross trainer takes your HR doesn't mean it uses it to calculate calories burned.
    Also like others have mentioned, what data you entered may make a difference.

    In the end, they are all just estimates. I always go with the lowest.

    Here are a couple of blogs that may help answer your question a little better

    http://www.myfitnesspal.com/blog/Azdak/view/exercise-calories-sometimes-the-cardio-machines-are-more-accurate-404739

    http://www.myfitnesspal.com/blog/Azdak/view/the-real-facts-about-hrms-and-calories-what-you-need-to-know-before-purchasing-an-hrm-or-using-one-21472

    800 is quite a high reading, I would go with the lower amount for sure.
  • sfbaumgarten
    sfbaumgarten Posts: 912 Member
    The HRM will be more accurate, especially if it uses a chest strap.
  • 3dogsrunning
    3dogsrunning Posts: 27,167 Member
    The HRM will be more accurate, especially if it uses a chest strap.

    Not necessarily, although in this case it probably is.
  • mucirl
    mucirl Posts: 17 Member
    I am given an option to enter my weight and age but not my sex or height .
    If I set up an account then perhaps I get an option to do this. I will try but I don't think it will add up to 300 cals
    I use a wahoo chest strap.
  • mucirl
    mucirl Posts: 17 Member
    I had been eating them back until I realized that there was a deviation.
    The mfp calorie count for 60 min is also very high
  • mucirl
    mucirl Posts: 17 Member
    I am also waiting to hear. Good point for not eating all calories back..lol

    I think we will have to eat less
  • 3dogsrunning
    3dogsrunning Posts: 27,167 Member
    I had been eating them back until I realized that there was a deviation.
    The mfp calorie count for 60 min is also very high

    The MFP estimate will be the least accurate since there are any number of variations that will affect the calorie burn. It does not account for intensity or resistance, it is a very general entry.

    Anotehr good explanation
    http://www.myfitnesspal.com/blog/Azdak/view/estimating-calories-activity-databases-198041
  • ninerbuff
    ninerbuff Posts: 48,982 Member
    Don't trust that the machine is accurate. Unless they are calibrated consistently (which is rare), the consistent use by many members on a daily basis will throw calibrations off.

    A.C.E. Certified Personal and Group Fitness Trainer
    IDEA Fitness member
    Kickboxing Certified Instructor
    Been in fitness for 30 years and have studied kinesiology and nutrition
  • cwolfman13
    cwolfman13 Posts: 41,865 Member
    You want to be as conservative as possible when you're doing the MFP method and eating back exercise calories. A HRM is still an estimate, but it is more accurate for an aerobic event for calorie burn than most any machine will be and certainly more accurate than any database or online calculator. When I was doing MFP, I sill deducted around 20% for estimation error.

    Also, a good way to think about this is that burning more than about 10 calories per minute beyond your basal calories is tough to do. 10 calories per minute is working hard...I never logged anything more than that, and I only logged that if I was performing an exercise that throughout the entire event there would have been no way I could hold a conversation and basically just had to focus wholly on my exercise. To boot, such an effort was pretty difficult to sustain for more than about 30 minutes or so. Basically I would put a 10 if I was running a 10 minute or less mile. I generally used a factor of 5 per minute for a brisk walk.

    Keep in mind also that your HR may not be a good indicator at all. If you are out of shape, your HR is going to be higher during certain activities than it otherwise would be if you were more fit...this does not mean you are burning more calories even though that's what your HRM will tell you. It just doesn't work that way and it's not as simple as having a HR at XXX BPM and you burn Y calories...your HR does not actually determine your calorie burn, it's just used in the algorithm to determine a reasonable estimation of VO2 max to which you are working.
  • erickirb
    erickirb Posts: 12,294 Member
    Treadmills and exercise bikes are pretty much the only cardio machines that use tested and true method of calculating calories burned, as long as you also enter, age, weight and gender, all other machines not so much.

    I would go by the HRM, but even that may be a little overstated as HRMs are more accurate during steady state cardio.
  • luv_lea
    luv_lea Posts: 1,094 Member
    I would trust the HRM over all other methods.
  • kdeaux1959
    kdeaux1959 Posts: 2,675 Member
    Take the least number and divide by two... then eat back about half of that... Those evil calories are hard to burn...

    Actually, the 500 is probably about right but do remember that if you are just sitting in a chair you are burning SOME calories... Therefore, your actual ADDITIONAL burn will be less than whatever your true burn is...

    Hypothetical example...

    1 hour of exercise - 500 calories by measure
    1 hour of sitting in a chair - 100 calories by measure
    Actual additional burn would be 400 calories for the hour.

    (These numbers I pulled out of the air but are set to prove a point.)
  • mucirl
    mucirl Posts: 17 Member
    Thanks to everyone I will go with the lower number. I will have to reduce the number of aperol spritzs I have!!!!