Training & Nutrition - how many calories am i burning?

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View Full Version : how many calories am i burning?


big
06-22-04, 09:14 PM
hey everyone. i'm looking for a good way to tell how many calories i'm burning say when i'm out for a ride or just in the gym lifting weights...how can i do this?


slvoid
06-22-04, 09:21 PM
www.caloriesperhour.com

big
06-23-04, 12:59 AM
there must be a better way than that..i'm looking for maybe some sort of electronic device that i can wear and somehow it does the estimate...


F1_Fan
06-23-04, 01:30 AM
there must be a better way than that..i'm looking for maybe some sort of electronic device that i can wear and somehow it does the estimate...

Polar HRMs will do this for you...

John M
06-23-04, 04:55 AM
As noted my Polar does this for me. I wear it at the gym, on the bike and when I fly my kites. I even down load the ride data :)

slvoid
06-23-04, 07:41 AM
As noted my Polar does this for me. I wear it at the gym, on the bike and when I fly my kites. I even down load the ride data :)

Biking AND flying a kite, now that's a way to add resistance. :)

The more expensive polar devices have this thing that estimates your calories burned from your heart rate. Mavrick has a computer and hub combo that costs $1000 that will actually measure wattage. I believe polar also has a similar device that estimates wattage.

jfmckenna
06-23-04, 08:15 AM
Ive got a cat eye HRM/Bike Computer that you can use in the gym or any where. I paid $50 for it on sale 1/2 off. It measures calories based on HR. And I find that the results I get from it are far lower then results that any of the calculators produce.

pacesetter
06-23-04, 08:39 AM
there must be a better way than that..i'm looking for maybe some sort of electronic device that i can wear and somehow it does the estimate...


The polars cal estimate i would take with a grain of salt these are only round about figures based on age, weight, height ect, the fitter you get the less cals are burned. the accurate way to determin is with a wattage meter i reccomend the powertap or SRM the polar watt meters are very very inaccurate.

SSP
06-26-04, 08:04 AM
My CycliStats training diary (http://www.CycliStats.com ) automatically estimates calories burned for each ride based on a number of factors (rider weight, bike weight, distance, time, elevation gained, etc.). It also summarizes calories burned by week, month, etc., and can convert that to the equivalent "fat pounds burned" (3500 calories = 1 lb of fat). You can download a free trial version from the website.

WAR85
06-27-04, 11:12 AM
http://www.healthstatus.com/cbc.html

F1_Fan
06-27-04, 11:28 AM
The polars cal estimate i would take with a grain of salt these are only round about figures based on age, weight, height ect, the fitter you get the less cals are burned. the accurate way to determin is with a wattage meter i reccomend the powertap or SRM the polar watt meters are very very inaccurate.

While I agree that the Polar isn't the best option available it's not as simple as you describe. The unit (at least my 710i) uses time of exercise and the HRM data for the ride as part of the estimation.

Evidence:

I ride a 28.5 km hilly loop as a periodic fitness test at least 4 time a month.

Here are two exercises one week apart. The only variable was heart rate time in the different zones (no change in the user information fed to the HRM and the ride times/ av. speed are identical).

ride #1: 1069 kcal hi: 52%, med: 47%, lo: 1%
ride #2: 960 kcal hi: 43%, med: 55%, lo: 2%

That's a 109 kcal difference based solely on HR data.

Here's another example. Same ride comparison but from early season time I wasn't pushing so hard. Again, same route, same time.

ride #1: 867 kcal hi: 12%, med: 80%, lo: 8%
ride #2: 712 kcal hi: 8%, med: 83%, lo: 9%

pacesetter
06-27-04, 07:30 PM
While I agree that the Polar isn't the best option available it's not as simple as you describe. The unit (at least my 710i) uses time of exercise and the HRM data for the ride as part of the estimation.

Evidence:

I ride a 28.5 km hilly loop as a periodic fitness test at least 4 time a month.

Here are two exercises one week apart. The only variable was heart rate time in the different zones (no change in the user information fed to the HRM and the ride times/ av. speed are identical).

ride #1: 1069 kcal hi: 52%, med: 47%, lo: 1%
ride #2: 960 kcal hi: 43%, med: 55%, lo: 2%

That's a 109 kcal difference based solely on HR data.

Here's another example. Same ride comparison but from early season time I wasn't pushing so hard. Again, same route, same time.

ride #1: 867 kcal hi: 12%, med: 80%, lo: 8%
ride #2: 712 kcal hi: 8%, med: 83%, lo: 9%


Yes time and hrt also i agree, i use a polar with them features. still everyone is differant if me and you did the same ride at same pace or (watts of power) we would burn a differant # of cals. the polar is good for a est,just like rest of them including ,the online calculaters.

SSP
06-27-04, 08:15 PM
While I agree that the Polar isn't the best option available it's not as simple as you describe. The unit (at least my 710i) uses time of exercise and the HRM data for the ride as part of the estimation.

Evidence:

I ride a 28.5 km hilly loop as a periodic fitness test at least 4 time a month.

Here are two exercises one week apart. The only variable was heart rate time in the different zones (no change in the user information fed to the HRM and the ride times/ av. speed are identical).

ride #1: 1069 kcal hi: 52%, med: 47%, lo: 1%
ride #2: 960 kcal hi: 43%, med: 55%, lo: 2%

That's a 109 kcal difference based solely on HR data.



I question the use of HR data in this case. Calories burned is a function of the physical amount of work performed. Heart rate is only loosely related to calories burned...in general, at higher rates of work, your heart rate is higher.

But, if you do the same ride twice at the same speed, under the same conditions (same weight, same wind, same temperature), the calories you burn will be the same, despite differences in heart rate.

pacesetter
06-27-04, 08:56 PM
I question the use of HR data in this case. Calories burned is a function of the physical amount of work performed. Heart rate is only loosely related to calories burned...in general, at higher rates of work, your heart rate is higher.

But, if you do the same ride twice at the same speed, under the same conditions (same weight, same wind, same temperature), the calories you burn will be the same, despite differences in heart rate.

Hummm.... do you have evidence hrt is loosely related to cal burn?

SSP
06-27-04, 11:34 PM
Hummm.... do you have evidence hrt is loosely related to cal burn?

Sure...it's the reason that top athletes are training with power meters. Heart rate can vary from ride to ride, depending on fitness levels, rest, etc. Two rides done at the same power can have different average heart rates. But, if they are done at the same power output (watts), they result in the same calories burned (assuming rider weight and bike weight are the same).

Power and calories burned are a function of the amount of physical work performed. Heart rate just tells you how hard your heart is working to produce the work. In general, higher levels of work result in higher heart rates, but not always. HRM's use this to help estimate calories, but they can be fooled by changes in heart rate, levels of training, amount of rest, and all the other things that can affect heart rate.

supcom
06-28-04, 06:02 PM
I suspect that athletes do not use power meters for estimating caloric expenditures. they are best used in conjunction with an HRM to determine how effeciently they are generating the power to the bike.

Neither power meters nor heart rate monitors will give you an accurate and repeatable measure of calories burned.

The heart rate monitor applies an algorithm based on gender weight, VO2max(?), and heart rate to estimate the calories burned during an exercise. As anyone who has used a heart rate monitor knows, even after you stop exerting yourself, your heart rate stays elevated for a significant period. This and general errors between the algorithm and the individual will certainly reduce the accuracy of the estimate.

Using a power meter is not without it's inaccuracies either. The power meter measures the output power of the body, NOT the rate of energy usage. It does not account for the inefficency of the human. This is a significant energy loss. For example, typically, it is estimated that cycling burns approximately 600 kilocalories/hr. If you do the conversion, you will find that this equates roughly to 600 watts of power. I doubt there are many forum readers who could generate an average 600 watts of output over an hour period. That's close to one horsepower (746 watts)! The difference is the inefficeincy of the body. All that heat you generate while cycling is wasted energy that does not propel the bike. In addition to basic ineficiencies, how a cyclist pedals can affect the efficiency. If you run a high cadence, you are lifting your legs more for the same power output which wastes energy. If you stand on a climb, you have to lift your whole body more than if you stay seated. This wastes energy. These are all things that can vary ride to ride, even with the same output power. So, if we are to use a power meter to estimate calorie expeditures, we must multiply in a large inefficiency factor and that factor is still an estimate - esepecially if you have not had it clinically determined.

The bottom line is that there is probably no tool available to the average cyclist that can approach an accurate measurement of calories expended. Use whatever estimate you like (printed table, HRM, power meter) and don't worry about it.

plimpington
06-28-04, 09:33 PM
I have been using various internet sites which list calories burned for various activities such as:

http://www.healthstatus.com/cbc.html
and
http://www.fitresource.com/Fitness/CalBurn.htm
and
http://www.nutristrategy.com/activitylist.htm

I am about 180 pounds at the moment, and according to these charts I am burning somewhere in the area of 1000 to 1100 Kcal an hour at my average pace (17 to 18 mph).

Frankly, I find these numbers incredible and don't believe them. On a flat road with little in the way of headwind, I can pedal along on my cheap Giant OCR1 at about 18 mph without much in the way of effort. It's a bit of effort, no doubt, but not would I would call "vigorous", which is what many of these tables call riding at between 17 and 19 mph. I would call it a "steady push" - with constant deep, but slow, breathing. I can't see how this burns 1000 kcal an hour.

By way of contrast, these tables peg jogging (or running) at a pace of 8 minutes a mile (a pace that would have me coughing up blood and bits of flesh after 10 minutes) at about 1000kcal an hour. I can attest to the fact that if I were to try to run for 60 minutes at a pace of one mile every 8 minutes, my chest would explode, and I would die right there on the street. Yet, I'm supposed to believe that an hour of riding at 18 mph burns the same number of calories. I don't buy it.

judd

supcom
06-28-04, 10:08 PM
I have been using various internet sites which list calories burned for various activities such as:

http://www.healthstatus.com/cbc.html
and
http://www.fitresource.com/Fitness/CalBurn.htm
and
http://www.nutristrategy.com/activitylist.htm

I am about 180 pounds at the moment, and according to these charts I am burning somewhere in the area of 1000 to 1100 Kcal an hour at my average pace (17 to 18 mph).

Frankly, I find these numbers incredible and don't believe them. On a flat road with little in the way of headwind, I can pedal along on my cheap Giant OCR1 at about 18 mph without much in the way of effort. It's a bit of effort, no doubt, but not would I would call "vigorous", which is what many of these tables call riding at between 17 and 19 mph. I would call it a "steady push" - with constant deep, but slow, breathing. I can't see how this burns 1000 kcal an hour.

By way of contrast, these tables peg jogging (or running) at a pace of 8 minutes a mile (a pace that would have me coughing up blood and bits of flesh after 10 minutes) at about 1000kcal an hour. I can attest to the fact that if I were to try to run for 60 minutes at a pace of one mile every 8 minutes, my chest would explode, and I would die right there on the street. Yet, I'm supposed to believe that an hour of riding at 18 mph burns the same number of calories. I don't buy it.

judd

Any chart that summarizes calories burned for an activity is going to reflect average conditions. In your case, you presented a scanario with no hills and no wind. The average bike ride has both and they certainly make a big difference in energy cost.

BTW, I just check my last two 'average' rides. According the calorie burn estimate from my Polar HRM, I am doing about 750 kcal/hr at about 16 mph average. I'd say that 1000 kcal/hr at 18 mph is in the ballpark.