InTheRain

I just did a calculation based on my weight (229 lbs) that indicated that cycling at 14-16 mph would burn 1374 calories per hour. My ride today was 31 miles at 15.2 mph. I've walked on a treadmill and tried to burn 1000 calories per hour. I'm completely wasted after 2 hours. But 2 hours on the bike at the pace mentioned above and I feel fine. The bicycling calculation is from thedailyplate.com.

UmneyDurak

It's waaaaaaay over estimating. On my two hour ride I burn around 1300 calories (if I convert Kj to C) thats with average 18-19mph.

Machka 

I estimate (roughly based on some calculators, etc. plus a personal calculation of quantity of weight lost vs. calories consumed) that I burn about 500 calories per hour. If you weigh a bit more than me, yours might be around 600 calories per hour. Approximately.

Walking burns about 300-400 calories per hour.

InTheRain

what "calorie calculators" are you using to come up with your numbers? I can see that weight would have a significant effect on calories burned when doing a weight bearing exercise such as walking or running, but it doesn't seem as though it would be as significant on the bike (unless you are climbing... that's when I know I'm putting much more effort into my cycling as I watch the light weights fly by me.)

Machka 

Have a look under the Health and Nutrition section on my Links page. The first three there have calorie counters.

https://www.machka.net/links.htm

But I also base my calculations on actual experience.

InTheRain

I found calculators on 2 of 3 websites from your web page. One said 1099 calories per hour and the other said 976 calories per hour based on my weight and average speed per hour. It still seems high. I trust the calorie calculations on the treadmill. Based on the effort between the treadmill and the bicycle, 600-700 calories per hour seems about right.

Machka 

If you are aiming to lose weight, base your calculations on your goal weight not your current weight. The numbers will probably be somewhat more accurate, and you won't be thinking, "Oh good, I've burned this many calories so I can eat this amount of food".

BryanW

I use a chart in a 20-year-old book, but it agrees with UmneyDurak's ~650 per hour at 18-19 mph. At 15 mph, it gives 400 calories per hour, or 24 per mile. It takes no account of weight, aero, hills, flappiness of clothing etc, but as a basemark it's always seemed accurate.

I wonder how much of the US/UK obesity crisis is caused by people using online calculators that tell them they've spent 1000 calories walking down the road to the pub?

garysol1 

Why not get a good Heart Rate monitor with a calorie burn function? While they are not 100% accurate they will give you a good idea of the work you have done.

Snuffleupagus

At 185-190lbs on a "steady state" training ride averaging ~280 watts per hour, I'll put 900kJ of work into the PowerTap. That is between 800-1000 calories. On easy, easy sub 150 watt recovery rides I'll put out 500ish calories per hour. On an hour long hard effort I'll put out more than 1100 calories.

If you're using the fitday calculators, I've found that over rollers I need to adjust the effort down a notch. For example, a hard two hour ride might net me 1900 calories per the power tap. If I use the 16-19mph cycling option, it's a close reflection of reality. If I use the 20+mph, it over estimates.

Also, please remember that you're an experiment of n=1. If you are consistent you will see results. If you're curious, you could get RMR testing at many higher end gyms, or at a hospital to better calculate your basal metabolic needs, get a polar HRM with the "own cal" feature, and subtract a solid 20% from those readings for cycling, and go from there.

CdCf

As a rough guide. 400-600 kcal/hour is about right for the majority, if we're talking regular distance riding. Not TT-like conditions, long intervals or hill repeats...

flip18436572

I would say that at my weight of 233 and riding at your pace and keeping a cadence of 90, I would barely burn 400 calories in an hour as my heart rate would never get to anything more than 100-105. It would depend upon the workout and your heart rate. Guessing around 600 max.

CdCf

Weight doesn't make much of a difference if you're in a flat area and don't stop/start often. If you ride in a hilly area, weight will make a huge difference.

Machka 

And even if you're riding in hills, you may work hard going up, but you're not exerting that much energy going down.


I wonder how much of the US/UK obesity crisis is caused by people using online calculators that tell them they've spent 1000 calories walking down the road to the pub?

I wonder too! So many people I've talked to overestimate what they are burning, and underestimate what they are eating.

CdCf

In terms of time, though, time spent going down is typically very short compared to the time spent climbing.

If you climb a 10 % grade for 3 km at 12 km/h, it takes you 15 minutes. Assuming it's safe to do so, you could easily descend the same route in four minutes. So, you spent 19 minutes riding up and down, but 15 out of those 19 were spent at a high level of effort, and only four coasting or gently pedalling. The average speed would be 19 km/h.

Compare that to riding 6 km on a flat road at 19 km/h...

UmneyDurak

Just curious what is your opinion of power meters values they report. Most display total Kj used during a ride, and I keep hearing different things on how to convert that in to Calories. Some say 1 Kh ~ 1 C, others say it's waay less then that.

CdCf

Assuming a 20 % efficiency for the human body when cycling, the total power to crank power ratio is about 4:1, and since the kJ/kcal ratio is also ~4:1, a power meter crank output in kJ could be taken as kcal body output straight off.

dobovedo

The online calculators simply don't have enough data and are very broad. For example, some people would have their heartrates maxed to go 15 mph whereas I consider it a Sunday stroll of about 60% effort. As others mentioned, using the light or moderate options on them is at least close, but the 20+ setting assumes you are pretty much going all out on a TT and even then I think it's too high.

There are sooo many factors that come into play on a bike. The type of bike you ride, body position, tires, even air temperature. Then there's terrain and wind. I put your numbers into my CycliStats software at my weight (160) and a 40 degree air temp on a flat course and semi-aero position on a road bike and got 461 calories per hour. Using your stated weight bumps it to 511, about 10% higher. However, using a mountain bike, upright position and a rolling course bumps it all the way up to 909. None of these come close to 1374.

I would suggest getting an HRM if you want a more accurate picture. It can be used on both the bike and the treadmill or for any other exercise.

InTheRain

Thanks for doing the calculations. I have a heart rate monitor that I've used on the treadmill (I love using it there as the incline on the treadmill automatically adjusts to keep your heart rate at the target that you select) but I've never bothered to use it on the bike. Is there a "calculator" that will convert average heart rate to calories?

p2000

That was what came to mind while reading this thread. I have a Polar F6 that recirds age, weight and heart rate. It also reads calories burned. I usually look at this info, but really have no idea how accurate it really is. But since it calculates target heart rate during the ride, how accurate is it?

Again it's not so much that I rely on that function, but I'd just like to know.

umd

I think that the 40 cal per mile estmate is reasonable. Factors intensity in somewhat because if you are going harder, you cover more distance (an burn more cals) in the same time. Of course its still just an estimate and is different for each person.

CdCf

I use ~20-25 kcal/km, which is ~30-40 kcal/mile.

dahoss2002

I like the 30 - 40 cal per mile formula too. Especially when Im counting calories to replace.

TurboTurtle

Using the Work from a power meter and an estimation of your efficiency (I've seen estimates from 19-26%) you can estimate Calories within + 5-15%. An HRM is much worse It simply does not have enough data. Calculating by time or miles in cycling doesn't work because, due to the wind, the effort can double with a small change in speed. - TF

umd

Yes, but the time/distance estimation is better than nothing, and the HRM is better still. Not perfect, but a reasonable rough guide. I've found that 40 cal/mile usually comes pretty close to what my HRM estimates for typical riding (moderate pace, rollers, a few climbs, but no mountain passes) on longer distances. It usually comes in about 1000 cal for 25 miles. Add more climbing or more wind or more intensity and it goes up. I did a ride last fall that was 100 miles with about 8000 feet of climbing, but a nasty headwind for the last 40 miles (and it was not a loop, so it was not a tailwind for the rest of it, it was mostly protected by a mountain range). That ride came out well over 5000, maybe even close to 6000 for the 100 miles, whereas that ride the previous time I did it was estimated closer to 4000, where I would have expected it to be.

I'll be getting a power meter soon, so I'll be able to test the relationship between the HRM estimation and the power meter's readings.