The Fat Cyclist Explains: How Cyclists Expend Calories

07.26.2011 | 11:19 am

A Note from Fatty: In the sporadically occasional “The Fat Cyclist Explains” series, I — the Fat Cyclist — explain things. Including, apparently, what seems to be a fairly self-explanatory series name.

One of the very best things about being a beloved Internet cycling celebrity is the fact that, merely by writing about bicycles on a frequent basis, I have become an authoritative expert on everything even tangentially related to bikes. For example, I’m very qualified to tell you what kind of bike you should buy next. I’m perfectly capable of giving you sound advice on bike maintenance and repair, even though I personally take my bikes into the shop for both.

And as a person who constantly battles weight issues, I’m exactly the right person you should go to for nutrition advice.

Thus, today’s question, submitted by me using the pseudonym “Duane,” is as appropriate as it is timely.

Dear Fatty,

I’ve noticed that a lot of cycling computers, GPSs, and ride-tracking applications give you information on how many calories you burned during a given workout. Can you use that data to calculate how much weight loss you should expect?

As always, thank you for writing the best blog that has ever been created in the history of the universe,


Wow, imaginary person I’m calling “Duane,” thanks for your question! You can in fact use the “calories burned” report from your GPS / bike computer / iPhone app / whatever to accurately project your change in weight. Just remember, there are 3500 calories in a pound, so you just have to do the math.

Sadly, however, that math is not quite as simple as you might think.

201107260926.jpg The Law of Extremely Diminishing Returns

Suppose you just went on a really long mountain bike ride: 76.5 miles, with more than 10,000 feet of climbing. Your GPS might tell you that you’ve expended 4,472 calories.

So you should have lost 1.28 pounds, right?


Unfortunately, no exercise computer takes into account several critical factors in calculating your calorie expenditure.

Critical Factor 1. Cumulative Time Spent Biking Over The Years

The most important thing your calorie-computing software overlooks is the fact that as you become a more experienced cyclist, you also become a more efficient cyclist. Which is to say that when you first begin cycling, you actually burn way more calories in a workout than the bike computer gives you credit for.

Unfortunately, as you ride more, you’re going to start riding better. You’re going to turn the cranks smoother (smootherly?), more efficiently. You’re going to stop bobbing your head and thrashing your body around during the climbs. Unless you’re Thomas Voeckler, of course.

You’re going to, in essence, go further with less effort.

The following highly-scientific and professionaly-produced chart illustrates this effect by plotting how many calories you can expect to spend when riding 100 miles on your bike, once you factor riding experience in.


As you can plainly see, by the time you have been riding 12 years, you can expect to expend a scant quarter of the number of calories as you did when you first started riding.

This is, at least in part, why you hear about cyclists going on longer and longer rides as they become more experienced. They have to, just to expend the same number of calories they used to when they went on much shorter rides.

But there’s a vicious cycle at work here. Or a slipper slope. I’m not sure which. Maybe it’s a slippery slope that eventually curves back on itself, becoming a vicious cycle.


The problem — which is either a slippery slope or a vicious cycle — is that as you ride more in order to burn more calories, you gain experience and efficiency, thus making it so that you need to ride yet even still more in order to burn the same number of calories.

And the problem gets worse.

As, over the years, you continue to ride, you burn fewer and fewer calories, until you reach what as known as the Paradoxical Cycling Calorie Cataclysm Threshold (PCCCT, pronounced “pkkkhht”), as shown below:


For those who are not quite certain, what you suspect is in fact the case: somewhere around your fourteenth year of riding, you stop burning calories when riding, and begin creating them. In defiance of what scientists know so far about physics, you start creating matter by expending energy.

At which point, the more you ride, the more weight you gain. Unfortunately, the converse — that if you ride less, you start losing weight or at least don’t accrue weight as fast — is not true.

Which is a shame.

Critical Factor 2. The Food Factor

The second factor calorie-counting software doesn’t take into account is the fact that as you ride and (hopefully) burn calories, something mysterious is going to happen to you:

You are going to get hungry.

When this happens, you must choose one of two options:

  1. Ignore the hunger, causing it to grow exponentially.
  2. Eat something.

If you choose option 2, you will invariable consume an amount approximately equal to the number of calories you have burned, causing the balance of the universe to be restored, and also causing you to not lose any weight.

If, however, you choose option 1, you will discover that eventually you will be unable to resist the hunger and will eat everything in your fridge, as well as — if you have a key to their house — in your neighbor’s fridge. At which point you will have incurred a calorie surplus equivalent, roughly, to 2.5x the number of calories you have consumed.

But you’ll be eating that during your post-workout high-metabolic recovery window, so those calories won’t really count.

Just kidding! They count even more than normal calories, actually. Because they’re guilty, no self-control calories.

Critical Factor 3. Problematic Calculations

The final factor you need to account for when looking at the number of calories software projects you have expended has to do with the “Fuzzy Logic” algorithms the software uses in its calculations.

What does this mean? Well, in order to give you a real-world assessment of your workout, the software takes your weight, the distance you traveled, the amount of climbing and descending you did, the ambient temperature, the phase of the moon, and several other factors into consideration.

This is when “fuzzy logic” comes into play, which means the software ignores all that data and picks a random number between one and ten thousand, which it then reports to you as the number of calories you have expended.

It’s very useful data, and I recommend you trust it explicitly.

PS: Hey, we’ve got artwork ready to go for the Grand Slam for Zambia: 1000 Bikes, 1000 Lives Changed project. Check it out:


You’ve got to admit: this would be a pretty awesome sticker to have on your bike, and it can be yours if you buy a bike for a kid in Zambia, changing her life in a huge, awesome way. Read here for details of what Johan Bruyneel and I are doing and what you can win, and then go here to enter the contest.


  1. Comment by Dr. Lammler | 07.26.2011 | 11:39 am


    This theory gives credence to the rumors that Lance’s true reason for retiring from cycling was to go on a diet.

  2. Comment by Susie H | 07.26.2011 | 11:41 am

    perrrfect…so since I went for my first mountain bike ride in 21 years this week, I am at the optimal calorie burning time, especially if you add and subtract the 21 year hiatus! Yay!

    [decided to take Lisa's words from our conversation a couple of weeks ago to heart, "run = hurt, ride = no hurt, :)]

  3. Comment by Scott R | 07.26.2011 | 12:10 pm

    I think your description of ‘fuzzy logic’ is the most true thing ever written.

    Here at, we value truthfulness above all. Except pie. – FC

  4. Comment by Lisa | 07.26.2011 | 12:30 pm

    When I was 250+ pounds (out of shape, obese) I started swimming to lose the weight and I burned an insane amount of calories each session. The fitter I got, the more I lost, the less calories I burned. Now I am super fit, 110 pounds lighter and I swim 2 miles in 75 minutes and barely burn what I used to burn. It’s a struggle in the pool to burn a lot of calories for me.

    The more efficient your body becomes, the less you burn! That’s not necessarily a bad thing! :)

  5. Comment by MattC | 07.26.2011 | 12:33 pm

    Sadly Fatty, these formula’s only apply to those who do NOT have an eating superpower: ie, those of us who can consume FIVE pieces of cake and actually LOSE weight just from the effort to EAT said cake.

    And btw, rumours of my demise from being stabbed to death with plastic forks up in Davis was woefully inaccurate…to say I was “nearly” stabbed to death would be more accurate.

    And a Sad but true fact here: I actually burn more calories reading a book than all of you poor humans do riding bikes (no matter how many years you’ve been riding).

    Also sad but true: I only survived my ‘near’ fork-stabbing death in Davis as I’m an expert at recovering from that type of injury…my wife routinely “nearly” stabs me to death due to her extreme jealousy of my superpower.

  6. Comment by Liz | 07.26.2011 | 12:34 pm

    Hmm . . . I wonder what the neighbors have in their fridge?

    Oops, sorry, got sidetracked there. Excellent post! Truer words were never spoken.

    Here at, we value truthfulness above all. Except pie. – FC

  7. Comment by muskyhunter | 07.26.2011 | 12:35 pm

    I have been riding for 27 years and there are days when I don’t feel like I’m turning the cranks that much more smootherly. Does this then affect the “calories burned” number in my cycling computer or “plastic brain” as like to call it?

    P.S. This kind of stuff is exactly why a friend tore his computer off his bike and threw it into a cornfield some where in Illinois!

  8. Comment by muskyhunter | 07.26.2011 | 12:37 pm

    btw, can’t wait for my sticker…

  9. Comment by Mr. Obtuse Wattage Geek | 07.26.2011 | 12:41 pm

    Actually, power meters give you a fairly accurate count of calories expended. The kilojoules measured by the meter will roughly equal the kilocalories you expended since a) 1 kilojoule = 0.239005736 kilocalories and b) the metabolic efficiency of most cyclists is around 23%. Ergo, for all intents and purposes, you can equate kilojoules with calories.

    Knowing this, and looking at the power files of Tour de France riders, you learn that they burn 5000 calories or more every stage (except TTs), which is roughly equivalent to 10 Big Macs. No wonder Chris Horner is such an exceptional cyclist!

  10. Comment by Jo | 07.26.2011 | 12:50 pm

    Excellent! I just don’t think it could have been explained better! Thanks! I think I am going to run with this!

  11. Comment by Mik | 07.26.2011 | 12:53 pm

    I think that any scone you eat while riding, especially one covered in powdered sugar, does not count towards your caloric intake.

    I am just saying…

    I second that motion. Anyone opposed? No? Motion carries. Powdered-sugar-covered scones eaten whilst riding shall henceforth be known as calorie-free. – FC

  12. Comment by fult23 | 07.26.2011 | 1:18 pm

    I think it should be said “more smoothly”. Additionally, metabolic freaks like MikeC make me want to nearly stab them with plastic forks. I guess that’s why the guards only let me have spoons?

    Let’s compromise on “Smoothlierly.” – FC

  13. Comment by fult23 | 07.26.2011 | 1:19 pm

    sorry MikeC, I meant MattC

  14. Comment by skippy | 07.26.2011 | 1:32 pm

    Interesting that you raised this subject today because it is the first recovery ride for me after the TDF !
    Weighed out after breakfast at 80kg and went Kramsack to Kufstein and back to find i was 79kg after 2 1/2hrs on the bike at relatively high pace .
    Lunched with the aim to enjoy the afternoon ride of Kramsack to Mayrhofen and return with visits to various friends along the route . Not a slow pace in the arvo either as there was a brutal face wind on the way back and weighed in at 77kg !
    Weather was sunny but not too warm though noticed a slight sweat at times .

    Another problem i am having is that i do not have a “Garmin / Computer / Polar ” to record the mileage to gain credit for ” fatty’s team ” fund raiser ” that you started a while back , so will one of your team assist , as by now my year is starting to look like the usual 10000+miles which would be a lot of pennies to the cause, don’t care who gets the credit as long as it does some good !

    Separate problem is that trying to post to “blogger ” seems to be blocked , can get the title of the post in but no content , any ideas to .

    Hope you don’t mind me saying that i had thought before the TDF that Cadel was unlikely to win , BUT delighted to apologise to him for a lack of belief in his perseverance , have been told that i was seen on Oz TV greeting him at the “presentation “!

  15. Comment by Elizabeth | 07.26.2011 | 2:06 pm

    Of course I am such a novice that I am sure I do an excessive amount of “bobbing my head and thrashing my body” even when NOT on climbs. Sadly, I have been known to grunt and sometimes call out to God on teeny, tiny climbs. Does this burn extra calories? Also, as a true novice, I have absolutely no ability to eat while riding because I would fall off my bike. Sometimes I can handle the water bottle.

  16. Comment by WheelDancer | 07.26.2011 | 2:13 pm

    If I got a fixie and rode backwards, could I reverse the PCCCT effect?

  17. Comment by Obstinate Roadie | 07.26.2011 | 2:15 pm

    Have you submitted this research paper to any sports science journals? I’m quite sure they’d be intrigued by your discovery of the PCCT.

  18. Comment by Diane | 07.26.2011 | 2:39 pm

    So, if we all adapt the Thomas Voekler riding style of bobbing and thrashing, will we continue to expend more calories or does your body become adjusted to this as well? Perhaps at that point you adapt another famous cyclists style to throw your body off.

  19. Comment by rokrider | 07.26.2011 | 3:17 pm

    @Diane, Thank you so much. Just the thought of an entire paceline of people bobbing and thrashing like Thomas Voelker absolutely made my day.

  20. Comment by Dan N. | 07.26.2011 | 3:36 pm

    More smoothly…sorry.

  21. Comment by Wife#1 | 07.26.2011 | 4:20 pm


    “… You’re going to stop bobbing your head and thrashing your body around during the climbs. Unless you’re Thomas Voeckler, of course.”

    Yeah yeah, the whole calorie thing is hilarious, but I am still chortling (yes, chortling) over the Voeckler crack. So very true.


  22. Comment by Trailer Park Cyclist | 07.26.2011 | 5:02 pm

    The proper phrase is “more better smoother”.

  23. Comment by aussie kev | 07.26.2011 | 5:05 pm

    i am still struggling to lose my “easter fat” – those calories are the hardest – i am sure smaller easter eggs have more calories than bigger ones….. or did i just eat more !!!

    very funny article (as always) check out these kids from africa this is how to ride a bike

  24. Comment by Micha | 07.26.2011 | 5:07 pm

    Ok then. What bike should I buy!?

  25. Comment by daddystyle | 07.26.2011 | 6:35 pm

    Love it

  26. Comment by Frank | 07.26.2011 | 7:08 pm

    The food in your neighbor’s fridge is free … and as we all know, free food has no calories. So in order to really lose weight riding, you have to eat everything in your neighbor’s fridge!

  27. Comment by gregc | 07.26.2011 | 10:33 pm

    I’d like to add a corollary to Fattys discovery of PCCCT- I call it the Business Travelers diet exemption: Any and all food eaten while on business travel is treated as negative calories and does not count toward fitness goals. Although I do not have any direct proof of this, it hoping it has to be true. While on a business trip in the deep south, I stopped in a Cracker Barrel for dinner tonight. Had it not been for the negative calorie business travelers diet exemption corollary, I’m sure I would have gained 5 lbs just reading the menu- and don’t get me started on what the scrumptious comfort food meal I enjoyed would have done. Ah, comfort food never tasted to good! I’m glad they do not have Cracker Barrel’s in Southern California, cause if I were to eat there while not on business travel, I’d weigh 500 lbs. (disclaimer- I do not own stock in nor work for Cracker Barrel- but I do enjoy comfort food!)

  28. Comment by LisaC | 07.26.2011 | 11:52 pm

    This analysis and presentation is to tight, I bet would love to get a nomination for you to present it at their next event. :)

  29. Comment by roan | 07.27.2011 | 7:20 am

    At my age and experience riding I’m way beyond the PCCCT so far thaat when I ride the calories are sucked out of my brain. But now thanks to Fatty I know why.
    My neighbors know me too well to even think about letting me have a key to their house.
    And the next bike that Micha will buy is one for Zambia.
    Q. about phases of the moon and calories/weight; I understand why when there is a new moon I weigh less and all other phases I’m either waxing or waning sort of a 28 days ebb and flow. But why is the moon always showing the same side ? Maybe you could ask the Full Moon Monte….er…the IT Guy.

  30. Comment by Fat Cathy | 07.27.2011 | 7:47 am

    Ah. The reason I’m still Fat Cathy has been explained. Thank you, Fatty!

    But I think you need to add age into the calculation somewhere.

  31. Comment by Katie | 07.27.2011 | 9:56 am

    I’ve donated half a bike so far, the other half will be donated soon :)

  32. Comment by (im)deebers | 07.27.2011 | 10:06 am

    Brilliant (as always). I Have a completely unrelated question though. I know you often ride the Alpine loop. Once the snow melts I make it part of my normal training routine and I have a question. Who is Susan? What race was she in and did she indeed win? I hate the fact that I know I’m not close to the summit until I see the ‘Win Susan’ on the pavement and I hate more that I know I still have at least half a mile to go when I do see it. Maybe if I knew who she was, and that the street graffiti actually aided in her eventual victory I would feel inspired instead of irritated. Can you help me?

  33. Comment by Doug (Way upstate NY) | 07.27.2011 | 10:43 am

    Duane thanks again for asking such an important question that has been on all of our minds! How do you do it?

  34. Comment by Liz | 07.27.2011 | 11:31 am

    Who is Susan?

    And she most definitely did win, because of her and many others there are cancer survivors like me alive in the world. Maybe you know some, too, and will find it inspirational in your Alpine rides.

  35. Comment by Mateo | 07.27.2011 | 12:46 pm

    Wow, my man love for you continues to blossom…all that Tucci-an hotness AND sage knowledge of the universal truths of cycling/weight loss theorems. Hold on, I need a moment…

  36. Comment by (im)deebers | 07.27.2011 | 1:51 pm

    Thanks Liz. That is a game changer perspective-wise. My final charge for the summit will have infinitely more meaning now. I don’t know that I’ll be faster but I’ll certainly feel more inspired.

  37. Comment by (im)deebers | 07.27.2011 | 2:08 pm

    PS I seriously had no idea. I figured getting an answer to this question was a long shot. Is it possible to feel both ignorant and enlightened? Humbled and inspired? Happy and sad? Cause that’s how I’m feeling.

  38. Comment by Trailer Park Cyclist | 07.27.2011 | 8:08 pm

    Pretty Cool, ain’t it? So now all you have to do is wake up every morning for the rest of your life and plan to kick ass.

  39. Comment by AK_Chick | 07.28.2011 | 12:17 am

    (im)deebers – Welcome to the world of Fatty (who is really actually Thinny). On a regular basis I feel all of what you felt when you learned about Susan and who she was and what she represents to us Fatty fans. :) If you continue to read Fatty’s blog, you’ll find lots of inspiration, not only from Fatty, but his fans. Welcome!

  40. Comment by 3d brian | 07.28.2011 | 10:27 am

    I really appreciate your informative posts but I found myself unable to follow the explanation due to the lack of conversion of calories into units that I can understand. Next time please include conversions to gigawatts, joules & jowls so that those of us with less familiarity with your scientific knowledge can keep up.

    Thank you Duane for you amazing questions that help to keep we in the cycling community informed.

  41. Comment by GJ Jackie | 07.28.2011 | 11:18 am

    Hey Liz(11:31 am), thanks for posting the link about Susan. Reading Fatty’s tribute again got me all choked up (again!) and reminded me of what really matters in life.

  42. Comment by Jenni | 07.28.2011 | 4:06 pm

    more better smoother…lol

  43. Comment by The Banter | 07.31.2011 | 9:30 am

    Fatty, according to Einstein’s famous E=mc^2 equation, energy and mass are directly proportional. In normal situations, matter becomes energy expended as kinetic energy and heat. According to the Fatty’s Paradoxical Cycling Calorie Cataclysm Threshold Theory, energy becomes matter. This is congruent with Einstein as equations work in 2 directions. I agree that more research and calculus needs to be done, but you seem up to the task.

  44. Comment by Michael McMullan | 08.4.2011 | 3:51 am

    Intersting article. i am cycling 2 years and have lost over 20kg. So i have 13 years left.

    Here is an article I posted on my blog about post cycle drinks/meals.

  45. Comment by Arnette Hoga | 08.21.2011 | 7:23 pm



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