Running V Cycling: Calorie Burn

m0scs

I used to run a bit but gave it up as a) it was boring and b) it caused me all manner of injury. I have since taken up cycling as a form of exercise and not looked back.

Anyway, a friend of mine has competed in the London Marathon a few times and likewise I have competed in charity bike rides of varying length.

I was wondering how may miles of cycling equated to a 26 mile marathon in terms of calories burned, assuming it was the same person performing the exercise on the same roads and all other things being equal.

My thought was that maybe 100 miles on the bike would equate to the 26 mile run.

What do you think?

liversedge

Runners world say that running 8 min/miles will burn 600-1000 cals per hour, depending upon your weight (110-200lbs range)

Cycling will typically burn 300 at recovery rates, 500-600 per hour at tempo, 1000 at threshold (according to my computrainer/cycling peaks).

Alex_Simmons/RST

liversedge wrote:

Cycling will typically burn 300 at recovery rates, 500-600 per hour at tempo, 1000 at threshold (according to my computrainer/cycling peaks).

Well that kind of depends on what your threshold power is.

At 1000 Cal/hr then your threshold is ~ 280 watts

liversedge

Fair point. I think 1000 per hour at threshold is a good yardstick for most of us here.

gtr mart

Can you work out watts and calories with just rider weight, distance and time?

I have read a few articles on watts calculations but most of them seem to say use a computer...

richa

No. Incline, drag, etc are all relevant.

Jumile

To put it into tangible terms, here's what this 115kg lardy got recently:

• Running: 2.15 miles @ 14:00/mile = 281 cal (or 130 cal/mile) - ok, so at that speed it was slow jogging
• Cycling: 7.86 miles @ 7:19/mile = 1,013 cal (or 129 cal/mile)

So, rather shamefully, if I could do a full marathon it would be the equivalent of a 26 mile ride. Hmm, my fitness has a long way to go... :shock:

liversedge

Jumile wrote:

To put it into tangible terms, here's what this 115kg lardy got recently:

• Running: 2.15 miles @ 14:00/mile = 281 cal (or 130 cal/mile) - ok, so at that speed it was slow jogging
• Cycling: 7.86 miles @ 7:19/mile = 1,013 cal (or 129 cal/mile)

So, rather shamefully, if I could do a full marathon it would be the equivalent of a 26 mile ride. Hmm, my fitness has a long way to go... :shock:

Keep it up and you'll be amazed how quickly you get stronger and thinner!!! Good luck.

Your comprison is between a brisk 30 minute walk and a slow 1 hr cycle. Your maths are out though.

At 250lb walking 14min/miles you will burn just under 90 cals a mile. Making the total burn about 194 cals for this walk.

Cycling at 8.2mph, on a mountain bike with thick tyres and weighing 250lbs with no wind but assuming you are tall and have a very large frontal area (1sqm) on the flat you will need to sustain an output of about 150w. Making the total burn about 486 cals for this ride.

Maybe Alex was right, if your threshold power is 150w then a 1000 cal per hour yardstick isn't so useful here.

m0scs

Interesting discussion.

I have a Polar CS200 cycle computer which gives me alot of data about calories burned etc but not about watts used. Not sure how you equate one to the other.

I weigh 100kg Age 44 and cycle regulary 20-30 miles on mtb with slicks to get fit lose weight although struggling on the latter.

On my last ride for example yesterday I have the following stats recorded.

Total Exercise time 1.hour 29 mins
Ave heart rate 164
Max Heart Rate 180
Calories burned 1526
Total milage 23.4 miles
Average speed 15.6 mph
Max speed 32.3 mph
Ave Cadence 79

This equates to 65.2 cal per mile.

Does this sound right and if so how do you calculate watts output?

liversedge

m0scs wrote:

On my last ride for example yesterday I have the following stats recorded.

Total Exercise time 1.hour 29 mins
Ave heart rate 164
Max Heart Rate 180
Calories burned 1526
Total milage 23.4 miles
Average speed 15.6 mph
Max speed 32.3 mph
Ave Cadence 79

This equates to 65.2 cal per mile.

Does this sound right and if so how do you calculate watts output?

You certainly worked hard for the ride!!!!!

Unfortunately, the power output can only sensibly be calculated using a power meter. There are a number of sites that you can use to estimate power however, but this require you to enter details related to speeed and ascent, without the ascent you are never going to get anywhere.

Looking at the data supplied can I guess that this was a fairly hilly ride?

I suspect that the Polar is guessing your power output from heart rate, this is decidely dodgy since this varies considerably from elite riders to weekend warriors. For example, when I am fully trained and on top form I can just about squeak 300w for an hour, right now I'm out of fitness and a lazy arse and can just about squeak 250w. My wife manages 200w and Boardman knocked out 400w for the hour record.

To calculate cals burned from watts is relatively straight forward, but again you have to factor in efficiency which is also highly variable but generally between 20-25% efficiency which goes to show how rubbish the human body is !!

Some links you might find useful though, for estimating power output: http://www.machinehead-software.co.uk/b ... lator.html or
http://www.cyclistats.com/tools.htm or http://www.mne.psu.edu/lamancusa/ProdDi ... ecalc1.htm or http://www.analyticcycling.com/ForcesPower_Page.html

My favourite online calculator from http://www.kreuzotter.de/english/espeed.htm has been removed which is a bummer.

BUT IN THE END, EITHER USE THE MIRROR TO GUAGE CALORIE BURN OVER TIME OR BUY A POWER METER AND CYCLING PEAKS IF YOU WANNA GET SERIOUS.

m0scs

Hi Liversedge.

Thanks for the comments. The ride I gave stats for has some steep climbs which pull down the average speed. Due to me carrying excessive weight, even though Im 6 feet 3 in I struggle on the hills and hence the reason for buying a MTB in the first place.(more gears)

I am improving slowly and did a 75 miler around Essex a few weeks back where the average speed was about 13.5ish over 5 hours and 20 mins

I think the Polar uses a combination of age ,weight ,height ,sex, sitting heart rate, and activity level to guage calorie consumtion but as to how accurate it is I dont know.

All I can say is that I push it when riding and try and keep the cadence up at about 80 rpm

Still I have a long way to go. Im looking forward to the day when I can keep up with some of the local road riders that pass me like Im standing still.

Cheers

steverile

Forgetting Watts, HRs, kCals and stuff, subjectively I'd give 100 miles on the road an easier score than a marathon. Offroad marathon felt a bit like 100 miles offroad, although obviously it's all over a bit quicker. Errm, it depends.

Jumile

liversedge wrote:

Keep it up and you'll be amazed how quickly you get stronger and thinner!!! Good luck. Your comprison is between a brisk 30 minute walk and a slow 1 hr cycle. Your maths are out though.

I wasn't doing maths - those numbers were directly from my Garmin Forerunner, based upon my stats (weight, age, etc) and measured heart rate. You could be right, though: perhaps calculating the numbers might give different values.

Thanks for the encouragement.

Alex_Simmons/RST

Jumile wrote:

I wasn't doing maths - those numbers were directly from my Garmin Forerunner, based upon my stats (weight, age, etc) and measured heart rate. You could be right, though: perhaps calculating the numbers might give different values.

Thanks for the encouragement.

Just bear in mind that unless you are measuring power, calorie/kj numbers shown by a cyclocomputer will be at best an approximation, at worst wildly off the planet.

Indeed I would treat such information as for novelty value only and definitely not be basing an assessment of calorie intake needs on it.

Jumile

Alex_Simmons/RST wrote:

...numbers shown by a cyclocomputer will be at best an approximation, at worst wildly off the planet.

This isn't something I'd given much attention to previously. Thanks for the advice. I'll look into better ways of measuring these values.

EBBC61

Not sure about the technicalities but I have real life experience as I used to run marathons before my knee injuries got too bad. At racing pace for a 2hr 50min time I usually lost about 10lbs in weight by the finish. Currently on a ride (not competitive, pleasure only but a good work out!) of anything between 20 miles and 60 miles I lose 1lb for each 10 miles. This is usually at about 17.5mph but when I time trialled in my younger days (65 now!) I would average 23mph in a 100 event so assume I would have used a lot more energy then but I didn't measure anything in those days, just rode as hard as I could when racing - we were not as educated in sports science and there were no electronic aids then. About two thirds of my weight loss on a ride returns within hours as I consume liquids and calories.