How do calorie counters work on ergs etc & how accurate?

General discussion on Training. How to get better on your erg, how to use your erg to get better at another sport, or anything else about improving your abilities.
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Gammmmo
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How do calorie counters work on ergs etc & how accurate?

Post by Gammmmo » June 21st, 2018, 3:48 am

As above, how accurate are C2 ergs, steppers, stationary bikes, treadmills etc when it comes to calorie monitoring? How do they arrive at the figure too? (topic possibly in the wrong place)
46M, 5'11" 73kg, ex bike time trialler.
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Targets: 36:59(10K), >8200m for 30mins, 6:44(2K), 3:12(1K)

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Citroen
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Re: How do calorie counters work on ergs etc & how accurate?

Post by Citroen » June 21st, 2018, 4:32 am

The C2 Calorie is the most inaccurate thing in the history of physics. It's based on an abitrary body weight, height and 25% efficiency at turning sensor watts into fake calories.

http://eodg.atm.ox.ac.uk/user/dudhia/ro ... #section11

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Re: How do calorie counters work on ergs etc & how accurate?

Post by Gammmmo » June 21st, 2018, 6:13 am

Can't see any reference to the height/weight etc of the "model" used for the C2 algorithm in that link. Anyone know what those are so a better approximation could be made (and how each factor affects the value either way)?
46M, 5'11" 73kg, ex bike time trialler.
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Targets: 36:59(10K), >8200m for 30mins, 6:44(2K), 3:12(1K)

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Re: How do calorie counters work on ergs etc & how accurate?

Post by Citroen » June 21st, 2018, 6:25 am

http://www.concept2.com/service/monitor ... ay-options

The PM3/PM4/PM5 calories are using the same junk formula.
That's why they give us: http://www.concept2.com/indoor-rowers/t ... calculator

bob01
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Re: How do calorie counters work on ergs etc & how accurate?

Post by bob01 » June 21st, 2018, 7:52 am

Surely ... rowing efficiency has to be a factor..
I assume op is concerned with calories burnt as opposed to time power generated

Two rowers same weight same height one with a 18min 5k the other with a 25min 5k at any given (provided it is doable) the slower rower has to be burning more calories!!

Is heart rate ( with individual parameters) more accurate.

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Re: How do calorie counters work on ergs etc & how accurate?

Post by hjs » June 21st, 2018, 8:58 am

bob01 wrote:Surely ... rowing efficiency has to be a factor..
I assume op is concerned with calories burnt as opposed to time power generated

Two rowers same weight same height one with a 18min 5k the other with a 25min 5k at any given (provided it is doable) the slower rower has to be burning more calories!!

Is heart rate ( with individual parameters) more accurate.
A faster rower can do more work per time unit, he is also more efficient, but still that does not make up for the faster pace.

Think every cal. Count is flawed, oxigion use should be measured to be more precise.
For my training see twitter @Hjsrowing

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Re: How do calorie counters work on ergs etc & how accurate?

Post by Steve1960VA » June 21st, 2018, 11:47 am

I don't really know, but I would have thought the simplicity of C2 ergs, with energy being put into a circular disc of known size & mass, would lend itself to fairly accurate calorie readings, if the displayed values are run through the C2weight-correcting formula. A lot of information can be taken off a spinning disc of known size & mass.

A few years ago, when I was able to burn a weight-corrected 1000 calories on the erg in a single, uninterrupted session, that took me about 1.25 hours.

According to some websites (such as ShapeSense), which offer "walking calories burned" formulas, my ~6-mile lake trail walk, which took me around two hours, was also a 1000-calorie burn.

I worked much harder on the erg, but for 45 minutes less, to burn the "same" number of calories. I always thought that seemed reasonable, so I've always assumed the weight-corrected erg calories were in the right ballpark. Not exact, of course, but fairly close - whatever that means.

Again, I don't really know. Just guessing.
Male. Virginia, USA. Born 1960. 6'4" (1.93 m). 268 pounds (122 kg). C2 Model D, PM 5.

Am erging for fitness. Weight loss OK if it comes.

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Re: How do calorie counters work on ergs etc & how accurate?

Post by bob01 » June 21st, 2018, 12:00 pm

Well I would have thought a hour hard exercise will burn more calories than easier exercise even for 2x as long. You are probably exchanging a lot more oxygen.


Then of course there is EPOC

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Re: How do calorie counters work on ergs etc & how accurate?

Post by hjs » June 21st, 2018, 12:11 pm

bob01 wrote:Well I would have thought a hour hard exercise will burn more calories than easier exercise even for 2x as long. You are probably exchanging a lot more oxygen.


Then of course there is EPOC
The difference between a hard and easy workout is not 50%, duration always will be the upper hand.

For a while I made some more meters. Instead of 30/35 I did 50 ish per day, this was enough to loose (unwanted) weight.
For my training see twitter @Hjsrowing

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Re: How do calorie counters work on ergs etc & how accurate?

Post by Gammmmo » June 21st, 2018, 12:18 pm

Steve1960VA wrote:I don't really know, but I would have thought the simplicity of C2 ergs, with energy being put into a circular disc of known size & mass, would lend itself to fairly accurate calorie readings, if the displayed values are run through the C2weight-correcting formula. A lot of information can be taken off a spinning disc of known size & mass.
This. Also, with some gym machines you actually input user details - admittedly this is often just age.

What got me thinking about this was a) on the Mindpump podcast the 3 guys, who are ex-trainers, were talking about the large amount of variation in accuracy of various machines through anecdotal tests they've done and b) my other-half has a cross-country skier type machine (not Concept2) and has reported what I thought were quite low calorie numbers - and she's not the kind to hold back on effort too as did IIRC a short 21min 5K on the erg in a competition after only having used it <10 times.
46M, 5'11" 73kg, ex bike time trialler.
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Targets: 36:59(10K), >8200m for 30mins, 6:44(2K), 3:12(1K)

Erg on!

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Re: How do calorie counters work on ergs etc & how accurate?

Post by bob01 » June 21st, 2018, 12:24 pm

hjs wrote:
bob01 wrote:Well I would have thought a hour hard exercise will burn more calories than easier exercise even for 2x as long. You are probably exchanging a lot more oxygen.


Then of course there is EPOC
The difference between a hard and easy workout is not 50%, duration always will be the upper hand.

For a while I made some more meters. Instead of 30/35 I did 50 ish per day, this was enough to loose (unwanted) weight.
Time trumping effort ... not if one excludes base calories ... I could sit on my ass all day and burn circa 2k cals. And only 500 exercising hard for 30mins... plus of course epoc!
Last edited by bob01 on June 21st, 2018, 12:34 pm, edited 2 times in total.

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Re: How do calorie counters work on ergs etc & how accurate?

Post by jackarabit » June 21st, 2018, 12:25 pm

https://www.ncbi.nlm.nih.gov/pubmed/17101527.

C2 does not attempt to include the EPOC phenomenon in its calculation of calories burned DURING ergisize. Why would it do otherwise? Add basal life support and EP(e)OC burn to caloric expenditure for 60’ MI, then eat a quiche or a cream pie, rinse and repeat. :lol:
There are two types of people in this world: Those who can extrapolate from incomplete data

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Re: How do calorie counters work on ergs etc & how accurate?

Post by hjs » June 21st, 2018, 1:19 pm

bob01 wrote:
hjs wrote:
bob01 wrote:Well I would have thought a hour hard exercise will burn more calories than easier exercise even for 2x as long. You are probably exchanging a lot more oxygen.


Then of course there is EPOC
The difference between a hard and easy workout is not 50%, duration always will be the upper hand.

For a while I made some more meters. Instead of 30/35 I did 50 ish per day, this was enough to loose (unwanted) weight.
Time trumping effort ... not if one excludes base calories ... I could sit on my ass all day and burn circa 2k cals. And only 500 exercising hard for 30mins... plus of course epoc!
:wink: Training or not base demand is a given...

Epoc certainly matters, but high intensity with high epoc needs long recovery. Long intensity with low epoc, needs much less rest. So again volume comes on top.
For my training see twitter @Hjsrowing

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Re: How do calorie counters work on ergs etc & how accurate?

Post by bob01 » June 21st, 2018, 2:35 pm

Sorry can't see it... So for burning calories longer slow trumps shorter harder work.

If one uses hr as a proxy for oxygen consumed which is linear up to threshold and then oxygen consumption increased faster.....

So over the 2hr period the easy session may have an average hr of 100 and the shorter harder set has an average of 120??

Then no matter how small epoc and then the harder set may produce more muscle.... which when resting will consume more cals

One might even look at TAD

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Re: How do calorie counters work on ergs etc & how accurate?

Post by hjs » June 21st, 2018, 5:02 pm

bob01 wrote:Sorry can't see it... So for burning calories longer slow trumps shorter harder work.

If one uses hr as a proxy for oxygen consumed which is linear up to threshold and then oxygen consumption increased faster.....

So over the 2hr period the easy session may have an average hr of 100 and the shorter harder set has an average of 120??

Then no matter how small epoc and then the harder set may produce more muscle.... which when resting will consume more cals

One might even look at TAD
You don,t want to see it.

I can do a serious 60min around 152, If I slow down to 2.00 can do that easily for a few hours, if I would slow to 2.10 I could do that a day long. A session of an hour will no produce much epoc, within 5/10 min my hf will be back to base.

Its a bit like weightlifting. A max rep is 100%
90% is around 5 reps
75% around 10

So at lower intensities you can do a lot more work. No difference with aerobic work. Look at cycling, max time trial is 400 watt, 4/6 hours daily tours around 200 av watt can and are done weeks in a row. And guys pulling the peloton are a good bit above 200 watt.
For my training see twitter @Hjsrowing

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