Cardio Accuracy, MFP or Machine?

In the current state of trying to lose, which means counting calories, I log my exercise calories. Most days I don't eat them back, but it's nice to have room for error. My question is this, when I log my calories burned into MFP, do I go by what the machine told me I burned or by what MFP says? Example: today- 20 min on recumbent bike (Im 3.5 wks post surgery) I biked at 14.6 level. My weight and age are entered on machine, just like on MFP. Machine tells me I burned 85 cal. MFP says I burned 217. That's a BIG difference! It does the same to me with the treadmill & elliptical- MFP ALWAYS way overestimates what the machine tells me. So, I log what the machine said. Which one is more likely to be accurate? (I know the whole... get a fitbit thing, but I have more important things to buy at the moment)

Replies

  • claraoswold
    claraoswold Posts: 89 Member
    I go by the machine. MFP has a ton of stuff they try to do and the sheer amount of code is probably daunting. A machine only has to do one thing, so the code on that is probably better.

    But then again, I'm an engineer, so I think like that.
  • anngroschup
    anngroschup Posts: 11 Member
    It's just crazy how the #'s are soo different! And I guess is MFP is going off of what someone else entered, a 400lb person may have burned 217 cal with 20 min of biking, but I highly doubt I did!
  • meridianova
    meridianova Posts: 438 Member
    personally, i base it off the machine's report. i use the treadmill, and MFP only offers 2.0, 2.5, and 3.0 options for speed (and considers 2.5mph a "leisurely pace"... bite me and my short legs) so i will tweak the time in order to match it to what the treadmill says i burned. since the machine is measuring my weight, speed, incline, duration, and heart rate, i figure those numbers are much more reliable than what's in MFP.

    the only downside is that i also do circuit/weight training, and there's almost no way to calculate the actual calories burned from that, so i keep the time low but still make sure something is logged.
  • anngroschup
    anngroschup Posts: 11 Member
    Yeah, I hate that it's so hard to calculate strenght training- even the fit bits don't do that :/ I figure I'll just use the calorie burn from the cardio and not worry about strength numbers. The strength is there for me to shape up, not neccessarily burn cals (even though it does that) I just don't count it
  • peter56765
    peter56765 Posts: 352 Member
    At the very least, you should have to enter your weight into the machine for it to have any hope of being accurate. A 300 lb person is going to burn a lot more calories doing the same workout on a machine as a 150 lb person. If you're logging and tracking, MFP already knows your weight.

    Conventional wisdom around here says the MFP estimates for cardio exercises are too high but I'm not sure what's behind that.
  • hmjohnson25
    hmjohnson25 Posts: 100 Member
    Both numbers are pretty generous. Get a heart rate monitor if you're looking for better accuracy.
  • wilsoncl6
    wilsoncl6 Posts: 1,280 Member
    I think MFP is pretty accurate if you are a muscular male, which is what I think they use to base their calibrations on. The machines are not always as accurate either because they need to be calibrated at certain times too to make sure they are functioning correctly, something a lot of gyms don't do regularly. Even if you were to enter your correct weight and age and use the heart monitors, there is no guarantee that you'll get the correct calorie burn. I always use the lower number as my base and enter that into MFP because if you report less calories burned that just means that you'll have a larger deficit. From my experience, using the elliptical, MFP has been pretty spot on for me as it generally matches what I see on the machines that I know have been calibrated.
  • Agree w/hmjohnsom25... Neither MFP or the machine are accurate regarding calories burned... Only a good HRM would be as close to accurate as you can get...
  • Jennloella
    Jennloella Posts: 2,286 Member
    neither.
  • RobPA1
    RobPA1 Posts: 48 Member
    Unless the machine asks you your bodyfat percentage and weight, there is no way this can be accurate. Calorie burn estimates on machines are usually VERY generous.
  • anngroschup
    anngroschup Posts: 11 Member
    Maybe for Christmas I'll get band of some sort ;) I knew machines were generous but compared to mfp, they're not. So to say both are way too high, almost seems like a lot of work for pretty much no calorie burn! Frustrating :/
  • jacksonpt
    jacksonpt Posts: 10,413 Member
    edited October 2014
    No way to know which is more accurate. Both are estimates based on calculates based on assumptions. The one whose assumptions are closest to your reality will be more accurate, but there's no good way to know which that is. For some people, the machines might be dead on while MFP is off, while for others it'll be way off and MFP will be much closer.

    Pick 1 method for estimating calories burned and use it exclusively for a month+ (I suggest the method that generally gives lower estimates, just to be safe). Then compare expected results to actual results. If they are close, then your estimating is reasonably accurate and you should keep doing what you're doing. If they aren't close, tweak and repeat the process.


    And as a side note, there's no way to guarantee an HRM will be any better.