Treamill running times vs calorie loss (Why do they differ?)

beccik1992

Hi all,

I am a very keen runner and do a lot of running, mainly treadmill based, i was just wondering whether anyone knew why some days i would do a 10KM run in 47 mins loosing (640 calories) then an alternative treadmill at the same speed etc however my calorie loss would be (600). I just want to know what kind of accuracy im looking at, i usually -10/20 calories off this for near accuracy.

Machka9

Gym machines aren't particularly accurate.

mcibty

What she said. This is where a FitBit comes in handy.

Kalex1975

With the caveat that all of this is just an estimation and a simplification, net calories burned by running and walking are distance/weight dependent, not time dependent. Use the following formulas...

Running:
Weight in Pounds X Distance in Miles X 0.63

Walking:
Weight in Pounds X Distance in Miles X 0.3

See more here:
https://www.livestrong.com/article/314404-how-many-calories-do-you-lose-per-mile/
https://www.runnersworld.com/training/a20801301/calories-burned-running-calculator/

spiriteagle99

I don't trust TM numbers at all. Mine says I burn 1000 calories an hour, running only 6 miles. Reality is half that. I use MFPs numbers, which are a lot more realistic.

heybales

beccik1992 wrote: »

Hi all,

I am a very keen runner and do a lot of running, mainly treadmill based, i was just wondering whether anyone knew why some days i would do a 10KM run in 47 mins loosing (640 calories) then an alternative treadmill at the same speed etc however my calorie loss would be (600). I just want to know what kind of accuracy im looking at, i usually -10/20 calories off this for near accuracy.

different software versions on the machine doing calc's slightly different.

Or if a really good machine, it was going by watts the motor had to use for you and your stated weight - but the motors read slightly different.

youngcaseyr

As @Machka9 already said, machines aren't always accurate, and wearables are not exempt. I wear a Garmin watch and it also gives me a little bit of variance in calories burned from day to day even though I run about the same distance every time, and I have been running on a treadmill for most of the winter. I chalk it up to differences in running effort and difficulty, whether I feel it or not. Humans aren't machines so some days are just easier or harder, even at the same pace and distance. If you ever increase or decrease your speed, do intervals, take walk breaks, etc, small changes can affect calories burned. However, when it's a difference of up to 50 calories for anything over 500 calories I would say that it's not a very big deal in the scheme of things.