Aderasmo23

Ok so i’m very confused. Today I did a small 25 minute session on the stationary bike at the gym. I averaged 6.5 miles in that time and my average speed according to the machine was 15.6 mph at a medium resistance. I looked at the watts after and it said 90? How is that possible and how many calories do you think I actually burned? I’m 5’8, 135 pounds and a female. I was definitely sweating and the machine only had me at burning 110 calories in that time period.

caloso

First, how many "miles" on a stationary isn't relevant. Nor is "speed." You're stationary, so distance is zero and speed is zero. Second, your height, weight, and gender are also irrelevant. All that matters is how much work you do.

Assume the power meter in the stationary is accurate (huge assumption, since they tend to be pretty unreliable), but let's go with it: 90 watts for 25 minutes = 2250 watt minutes = 135 kj of energy.

It's in the ballpark.

seypat

There's a dedicated indoor/stationary subforum in the Road Cycling forum.

Barry2 

This article might explain.

0.4 Hour x 90w x 3.6 = 135 Calories
A lot less than you hoped !

Barry

tempocyclist

Well... It's around 17 Haribo Starmix pieces!

LifeNovice1

More proof that you can never out-exercise a bad diet!

Milton Keynes

If only more people understood exactly how much exercise you need to do to burn off a couple hundred calories. I think most people tend to underestimate the number of calories they eat and overestimate the number of calories they burn. You're not going to burn off half a bag of Doritos by walking around the block.

PeteHski

True, but can also be surprisingly high. I managed to burn 859 cals in an hour on the bike last night. That's a good sized meal right there!

mstateglfr 

I religiously track everything i eat and any exercise(dedicated, not counting random steps i take in my home thru the day) and have done so for almost 2 years. I have done this twice in the past and it worked great each time, but I eventually stopped because I thought I could guesstimate and be good. Clearly I cant.

I have no idea how accurate everything I enter is, but the results are clear, so as long as everything entered is consistent(consistently accurate or consistently inaccurate), it doesnt much matter.
I enter all cycling related activities at 1 'level' below what I did. So if I rode 125min at 16.8mph, I will enter 125min at 12-14mph into the app, just to sorta be on the safe side. I do that because I think it overstates calories burned from cycling, even though I have absolutely no evidence of that being the case.

Anyways, not much point to this. I decided to post because though I agree with your Doritos comment, my block is exactly 1 mile around and based on the fitness and nutrition app I use, I can burn off half a bag of Doritos! Obviously the block size is an outlier.

Barry2 

Just don’t rely on ANY application using only heart rate to estimate calories.
Any chance at a reasonable calorie number really needs an actual power meter.

My wrist worn health tracker’s estimates are laughable.

Barry

mstateglfr 

How far off from 'real' are they? I assume you have a power meter that has been shown to be accurately calibrated so you then know your wrist tracker is way off.

Barry2 

Sorry I don't recall actual numbers for the difference and haven't compared recently. When I switched to a power meter two years ago I noticed the jump.

As for your calibration comment, I did a three way comparison for my cycling coach who questioned accuracy.
Garmin Vector 3 dual
Stages Gen3 Dual
Wahoo Kickr Bike

Vector 3 measured 3% high across the board compared to the other two.
So... All 3 were close and to *G.E. standards.

Barry



* G.E. - - Good Enough

LifeNovice1

This is interesting. I've lost 35 pounds since January using my Fitbit and app. I was very careful to measure what I ate at dinner time. Going as far as to measure sauce, etc with measuring cup and tablespoons. I found that keeping the old 250-500 calorie deficit worked. Probably wouldn't have worked if the Fitbit estimates were THAT optimistic. I found what the earlier poster said was true. I really understimate my calorie intake. Also I quit drinking which helps in too.

rsbob 

Doing the hard math, that’s 4.4 calories/minute. Seems like a fair amount. Indoor Sweat is not a great indicator of effort but it sure makes me feel like I’ve worked hard. Make sure you get a good fan, preferably a big box fan if you don’t have one or you will burn calories keeping yourself cool rather than in your workout.

jaxgtr

I ride to support my crappy diet....

burnthesheep

Beer is good but good beer also has serious calories. Like 500 for just a couple brews on a Friday night.

Twice a week, that’s 1000.

Lotta work on bike to take care of that!

If I could plot that on a chart the weight correlation is dead on.

cyclezen

sadly, this...
sweating on a stationary bike is so unrewarding !
about the same as a brisk 2 mile walk.
but, yeah, so many misjudge how much 'work' they've actually accomplished in any exercise/activity...
...but you likely did get some cardio work... and that's a good thing!
Thx
Yuri