Edge 305 & Calories

[steve]

Edge 305 & Calories

My new Garmin Edge 305 calculates the calories I have supposedly used
during a ride. Knowing the calories and time I should be able to
estimate my wattage for the ride. However, when I do this I get more
that a Kilowatt. I rode for slightly less than 2 hours and used 1750
calories. If I really could generate over a kilowatt for an hour I'm
in the wrong business. I know about the Kcal vs cal issue but neither
answer makes sense.

I figure there are three possibilities.

1 - The 305 over estimates the calories used.

2 - The number is the calories to run the old bod + what ever I have
to generate for the ride. This still doesn't maker sense to me
because, if I remember right, the base rate for a person is about 200
watts and I don't believe I can generate 800 watts either.

3 - I'm missing something here

BTW does anyone know what algorithm the edge uses to calculate
calories?


Thanks
Steve G

 

[Lou Holtman]

steve wrote:
> Edge 305 & Calories
>
> My new Garmin Edge 305 calculates the calories I have supposedly used
> during a ride. Knowing the calories and time I should be able to
> estimate my wattage for the ride. However, when I do this I get more
> that a Kilowatt. I rode for slightly less than 2 hours and used 1750
> calories. If I really could generate over a kilowatt for an hour I'm
> in the wrong business. I know about the Kcal vs cal issue but neither
> answer makes sense.
>
> I figure there are three possibilities.
>
> 1 - The 305 over estimates the calories used.
>
> 2 - The number is the calories to run the old bod + what ever I have
> to generate for the ride. This still doesn't maker sense to me
> because, if I remember right, the base rate for a person is about 200
> watts and I don't believe I can generate 800 watts either.
>
> 3 - I'm missing something here
>
> BTW does anyone know what algorithm the edge uses to calculate
> calories?
>
>
> Thanks
> Steve G


Divide it by 4. That's your efficiency. In: 1000 Watts, out: 250 Watts.
Bummer....

Lou

 

[steve]

On Apr 14, 12:20 pm, Lou Holtman <[email protected]> wrote:
> steve wrote:
> > Edge 305 & Calories
>
> > My new Garmin Edge 305 calculates the calories I have supposedly used
> > during a ride. Knowing the calories and time I should be able to
> > estimate my wattage for the ride. However, when I do this I get more
> > that a Kilowatt. I rode for slightly less than 2 hours and used 1750
> > calories. If I really could generate over a kilowatt for an hour I'm
> > in the wrong business. I know about the Kcal vs cal issue but neither
> > answer makes sense.
>
> > I figure there are three possibilities.
>
> > 1 - The 305 over estimates the calories used.
>
> > 2 - The number is the calories to run the old bod + what ever I have
> > to generate for the ride. This still doesn't maker sense to me
> > because, if I remember right, the base rate for a person is about 200
> > watts and I don't believe I can generate 800 watts either.
>
> > 3 - I'm missing something here
>
> > BTW does anyone know what algorithm the edge uses to calculate
> > calories?
>
> > Thanks
> > Steve G
>
> Divide it by 4. That's your efficiency. In: 1000 Watts, out: 250 Watts.
> Bummer....
>
> Lou

Thanks

250 is about what I expected.

Steve G

 

[BobT]

"steve" <[email protected]> wrote in message
news:69d708e3-649f-4a06-a9d7-7febc9f6e068@l64g2000hse.googlegroups.com...
> Edge 305 & Calories
>
> My new Garmin Edge 305 calculates the calories I have supposedly used
> during a ride. Knowing the calories and time I should be able to
> estimate my wattage for the ride. However, when I do this I get more
> that a Kilowatt. I rode for slightly less than 2 hours and used 1750
> calories. If I really could generate over a kilowatt for an hour I'm
> in the wrong business. I know about the Kcal vs cal issue but neither
> answer makes sense.
>
> I figure there are three possibilities.
>
> 1 - The 305 over estimates the calories used.
>
> 2 - The number is the calories to run the old bod + what ever I have
> to generate for the ride. This still doesn't maker sense to me
> because, if I remember right, the base rate for a person is about 200
> watts and I don't believe I can generate 800 watts either.
>
> 3 - I'm missing something here
>
> BTW does anyone know what algorithm the edge uses to calculate
> calories?
>
>
> Thanks
> Steve G

Your device is estimating calories burned. You may be comparing to power
applied to the pedals as measured by a device such as a powertap or SRM.

Your "motor" is not 100% efficient. You are expending calories to work you
brain, digest your food, grow your fingernails, etc. Perhaps 25% of your
caloric expenditure ends up being transferred to the pedals to propel the
bike.

BobT

 

[Rocky]

The efficiency of the human bod from input to output is about 25% or 20%
depending on how you calculate it.

If you include the calories you would have burned by sitting around then you
use the 20% number. That is, total energy burned divided by energy into
the pedals is 5.

If you don't include the resting energy then the ratio is 4. That is,
incremental energy used.

I also have an Edge 305 and I think it greatly (as in 2x) over estimates
calories burned. I have various other methods to estimate energy used and
they all give me a number about half of what the Edge does.

Rocky


"BobT" <[email protected]> wrote in message
news:[email protected]...
> "steve" <[email protected]> wrote in message
> news:69d708e3-649f-4a06-a9d7-7febc9f6e068@l64g2000hse.googlegroups.com...
>> Edge 305 & Calories
>>
>> My new Garmin Edge 305 calculates the calories I have supposedly used
>> during a ride. Knowing the calories and time I should be able to
>> estimate my wattage for the ride. However, when I do this I get more
>> that a Kilowatt. I rode for slightly less than 2 hours and used 1750
>> calories. If I really could generate over a kilowatt for an hour I'm
>> in the wrong business. I know about the Kcal vs cal issue but neither
>> answer makes sense.
>>
>> I figure there are three possibilities.
>>
>> 1 - The 305 over estimates the calories used.
>>
>> 2 - The number is the calories to run the old bod + what ever I have
>> to generate for the ride. This still doesn't maker sense to me
>> because, if I remember right, the base rate for a person is about 200
>> watts and I don't believe I can generate 800 watts either.
>>
>> 3 - I'm missing something here
>>
>> BTW does anyone know what algorithm the edge uses to calculate
>> calories?
>>
>>
>> Thanks
>> Steve G
>
> Your device is estimating calories burned. You may be comparing to power
> applied to the pedals as measured by a device such as a powertap or SRM.
>
> Your "motor" is not 100% efficient. You are expending calories to work
> you brain, digest your food, grow your fingernails, etc. Perhaps 25% of
> your caloric expenditure ends up being transferred to the pedals to propel
> the bike.
>
> BobT
>
>

 

[datakoll]

http://www.nytimes.com/slideshow/2008/04/18/world/0418-HAITI_index.html