Science of how body height affects cycling speed (why climbers are small and sprinters are tall)
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- Опубліковано 21 лип 2024
- Yes, if you are taller your aero (CDA) is worse, but what if you scale everything up, like-for-like, does a tall rider have an advantage? Why are most climbers, really small?
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0:00 Intro
0:59 Zwift caught height Cheating
2:05 What scales with height?
2:50 Comparison of 4 riders
3:14 CDA vs height
4:31 Vo2 vs height
5:14 Lean muscle vs height
6:30 Power vs height
7:10 Climbing vs Sprinter
7:40 Training vs height
8:22 Climbing vs Sprinter vs height
9.01 Zwift model of height is wrong
9:45 Why do tall riders win?
10:40 Don't go too thin!
11:20 Tables of Stats
11:40 Join our Strava Club - Спорт
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completed. Would you make your data / results public please?
@@9alpcen thank you! Did results come up after you completed it?
@@Fastfitnesstips no, nothing came back up
Cause for another video Alex :)
@@9alpcen sorry about that...I selected show results after completion in Google...but yes I will present on this at a later date
I think the fact that pro cycling isn't completely dominated by either short people or tall people like horse racing and basketball respectively tells us that height is not super important compared to other factors.
We already ran the numbers. 5'9" 145-150 lbs. Was the overall clear standout of all the winners by far. 1" taller or shorter and the numbers dropped by 1/2. The second was 6' 150 lbs.
@@oilcanracer6388 yup, I'm basically the second.
@@oilcanracer6388 not anymore
The only advantage of big people were to be assistant to block the wind and the advantage of small is they can hide easily on the wind using other rider but it's not that much issue or disadvantage to both because they could beat it down by their leg muscles strength and the bigger the weight you have the bigger power you would generate yet can be same speed to a lighter rider with less power generated
The real disadvantage for tall people is the aero bar UCI rules
being 6'3" I find people always like to get a tow, tall = great wind break :/
I'm 5'6" and I love to hide behind tall guys like you!
Josh Martonosi I’m 5’5” and me too :)
Advantage small guys, able to rest.
Thanks for the pull man.
We should all do our share lads, but proportionately though.
I do what I can when riding with taller guys. It'll make you stronger anyway and it's more fair on the tall lads
Well done! Your analysis is perfectly inline with my expectations. A comparison I often like to make is to the world record lifts done by athletes in various weight classes in weight lifting and power lifting. Even though these are maximal anaerobic efforts, I think they illustrate the point nicely. Shorter, lighter lifters can lift a greater multiple of bodyweight than taller lifters in heavier weight classes. And even if you factor in the shorter range of motion of the lifts, the lighter athletes are still producing more power relative to their bodymass. The same trend ought to apply in cycling, which explains why shorter, lighter cyclists are often superior climbers.
On the other hand, taller, heavier cyclists get to take advantage of the square-cube law when it comes to speed on the flats, and especially on descents. A rider's height and width contribute to their CdA, but not really their depth. However, height, width, and depth all have positive correlations with lean body mass and therefore power output. It's the same reason why heavier skydivers reach a higher speed in free fall than lighter skydivers.
However, it's interesting to see that a 190 cm rider has only a 2% flat speed advantage over a 160 cm rider, while the 160 cm rider has a whopping 11% climbing speed advantage over the 190 cm rider. Being that most of the time to be gained is on the uphills, this places tall riders at a statistical disadvantage everywhere except on a velodrome.
Excellent video and subject as always Alex. Most people are very quick to judge, suffer from a Dunning-Kruger effect and blame/scapegoating mentality, and simply don't know or understand how physics and a complex system like a human body actually works (and we are still learning about it too). They simply project from their own experience. Not taking into account that we are not all created equal, that some are doing multiple sports, that training (and its actual quality) for 10 years does not have the same effort as simply riding for 10 years, things like that.
What are you trying to say ? Don't see if you blame either cheaters, or people who report them.
Great video. Nice description of the problem, but still kept simple enough for the wider audience. You did really good job helps me to quickly jump on this topic. Just one note -> the Bresset formula for Frontal Area estimation is not completely correct, the power factor for height is missing. The formula should look like this A (m^2) = 0.0293 * height (m)^0.725 * weight (kg)^0.425 + 0.0604.
But this is just a totally minor thing. As mentioned above I really like this video -> I am definitely gonna check other videos from your channel.
I am that 160cm (between 52kg - 58kg ) rider in your example! I've always thought the taller cyclists I ride with (basically that's everyone) had an advantage aerodynamically. I can usually make it hard work on climbs for all but the strongest TTers, especially longer climbs where I'm usually minutes up the road on a 10k climb. However I struggle to get as efficient (compared to power output) especially in a TT position. Comparing myself to someone who is 6ft and around 85kg, I used to beat him regularly until he got a new TT bike with disc wheel, then the tables turned and he became quicker by a minute or more! So for example in one TT I rode with a power meter recording 2m12s with avg of 277w, he would be seeing 21m30s or better, however with an average power of only around 290w. I think I'd need to be over 300w to get as quick, which ain't gonna happen when you're 5'3" and not a pro!!
ur age?
did you try ridding on his bike ?
Trainer road podcast mentioned this. They also said the best pro climbers need to weight or have weighed 2lbs per inch.
So pros are fast because they have low bone density? Bone doping is the future. I want carbon fiber bone implants.
Jeff Ahlers The bike weight is 80% of their speed. At 6.8kg you can pick up their bikes with 1 finger. A 25 km head wind on a 6.8 kg is nothing compared to a 25 km hr head wind on a 14 kg bike ( my training weight bike) it is world's apart. No pro rider in existence is going to go up against an average cyclist on a 6.8 kg bike while the pro has to ride a 20 kg bike. Basically they only train on 6.8 kg bikes that is why their bodies reflect that weight training. This video makes no mention of what bike weights have on the riders. That is a basic principle which is missed.
Cortisone thins the bones.
Danfuerth Gillis r/wooooosh
Kleiner Helfer lmfao hahahaha good one, but adding weight on a backpack say 7 kilos would be a good start. I actually watched the GCN video on bike weight and how it affects climbing and overall times, let’s just say I stand corrected at the results of how slow a 7 kg weight added makes.
Good video with good info, ruined by excessively loud and annoying background music played at inappropriate times.
another often undervalued factor is leg length and muscle insertion. chris froome is exactly as tall as i am, yet he has a 2cm higher saddle high than i do, so i would think he has longer legs than i do, thus resulting in better leverage
Another thing is that your resistance from gravity doesn´t equal your weight, but your weight+6,8kg(If you are a pro), so taller and heavier riders don´t have that much disadvantage.
Good point Ondra! However be assured we put the bike weight into the model that calculated the speed differences.
Great video thanks! What about the co-variable of relatively wider shoulders and/or larger chest, to waist and lower body ratios; while keeping various heights and weights constant in your calaculations?
You are quite right Nick which is why this is an approximation based on basset CDA calc....for more accuracy you would need exact frontal area or wind tunnel data
Excellent video as always Alex. Your calculator seems to predict with a fair amount of precision what specific cycling discipline a rider of a particular height & mass will be best suited for. It is spot on for me, but it took me years of trial and error to come to the conclusion that your calculator lays out for anyone to see. Chapeau!
At six feet four find that I start fall back on myself on very steep MTB hills and the same with going down very steep hills, I start forward and over, I cannot get my saddle low enough to compensate.
Shift your weight mate. I'm 6'6, and I just make sure to shift my weight forward when going up, and I shift back when going downhill. Good luck! Maybe get a fitted bike
A point that is not being addressed in any of these discussions is body type. A person's dimensions don't proportionately go up with height. I'm 6'1" with fairly broad shoulders, but have a buddy who is 5'9" and his shoulders are almost an inch wider. He's not remotely fat, in fact we are both sub 10%, it's that his skeletal design is a very wide frame. Another buddy of mine, is same height as me, only he has a 30" inseam whilst mine is 34", and his waist is 4 inches wider (again, not because of body fat, he's got wider hips & mine are very narrow...yes, I am very "lanky". I automatically look like the "guy who always skipped leg-day"). The names of these different types are ectomorph, endomorph, & mesomorph (a good description can be found here: www.jefit.com/exercise-tips/three-different-body-types).
The fact is that some (like in the video) look at the comparison of a tall person next to a short person & quickly judge that the aerodynamic properties alone are so obvious...however, are they?? Isn't a cyclist typically bent over to the point that the squared mass of the torso will be somewhat "evened out".The distance from neck to waistline will have very little difference from tall to short, however what DOES factor is more that person's width (which, albeit you are trying to consider in the video - however, it is providing a very broad (pardon the pun) assumption.
Look at the different body types of Froome to Sagan (from the stats I've seen, these two are close to the same height & weight - yet, Sagan has a more muscular build), but then Contador to Cancellara, Valverde, Cavendish, Dumoulin, Porte, Griepel, Quintana, Kittel, Yates, , etc. etc. Unbelieveable cyclists who, yes, do have their "strengths & weaknesses" for comparisons of climbing, sprinting, & all that *in comparison within the pro ranks* AND are all very low on the body-fat measurements BUT have different BMI's.
(Again, from stats I'm found on the ever-truthful in-ter-web...so I'm just going with the data I can find) An example is that Nairo Quintana is 167 cm & 59 kg, so that'd give him a BMI of 21.2. Chris Froome meanwhile is 186 cms & weighs 69 kgs (the data from both riders was from the same site, so hopefully the data is "as of" a similar date... but the point is) that gives Froome a BMI of only 19.9. They are both insanely lean. Even though Quintana is shorter, I don't think that necessarily is gonna be much less wind resistant than Froome in a tuck. (Plus there's the whole leg/crank-arm length torque/effeciency issue that is ANOTHER whole mess of a discussion)
Granted - we are talking very minute differences here... but over the course of each hour if any of this makes a couple seconds worth of difference - that means a lot in this game of minimilistic gains. Quintana has a 6% higher BMI than Froome - I'd think that would make a larger aero-difference than all the fuss of people tucking their cables internally into their frames compared to routing them along the underside of the top tube. Not to mention all the fuss about tire width aero-properties.
--Now how this can/could/should/shouldn't be realized in the virtual world is understandably almost impossible. How do you calculate an ectomorph body type that has a beer gut? Or somebody that has mesomorph characteristics from the waist down but is ectomorph through the chest, shoulders, & arms? I don't think you can; so what you're describing in the video is p'bly the fair solution. Even though I don't like the aero loss I automatically receive as a tall rider, despite my overall lanky build. (a rider 5'9" that's the same weight as me, gets the same weight penalty in the calculations, but I get a reduction for my height - both of us in the riding position...p'bly doesn't have much difference in aero-reduction. Some, but p'bly not very much)
**not arguing or saying the data in the vid is wrong, just adding some food for the discussion** Thanks!
BMI has a square relationship to height. It's basically if you steam rolled someone into a square equal to their height and then cut out a square meter, how many kilograms would it weigh
Hi maximum muscle power is dependent on an optimum muscle length , falling if the muscle is shortened or stretched. If most cyclists have an inside leg of between 70 to 90 cm , shouldn't crank length should also have a 20 cm range not a stanard165 to 175 cm? Is there any science on the effect of leg length v crank length and power? Someone with 70 cm inside leg would have a vertical stroke length ( 0 to 180 degrees ) of 34 cm with 170 mm crank whereas a 34 cm stroke length on a 90 cm inside leg is proportionately less and the hip extensors are closer to their optimum length for the downstroke. If this is so, this biomechanical advantage could explain why timetrialists can be tall.
what music is that??? someone please tell me, i listened to it once and I've been looking forever for it
Idk, but I have heared it in a loooot of youtube videos.
Interesting stuff... but confuses me further. I’m on the taller side and heavier than the average you worked out, but compared to my cycling buddies I lose them on the flats during a hard effort but can pull away from them on climbs. I can only assume my position on the bike and therefore cda is poor
Chris froome snd wiggins at 6.5=6.6 fit were a very strong climers
Does the bike weight % of total watt per kg. give taller riders advantages on all terrain? example: 7.7kg bike adds 16.5% to a 66kg rider. The same 7.7kg bike adds 3% to 75kg rider. With these riders capable of equal watt/kg tested on stationary equipment (typical). The taller rider has an immediate advantage on all road conditions. Race results then, are the result of fitness, fatigue, planning and skills.
Interesting but I think your calculations are quite wrong. I get respectively 12% and 10% for the 66kg and 75kg rider. So it does make a difference but not as much 😉
Which is best for height gear or non gear cycle please reply
Still a big assumption, that leg to torso proportion remains constant. This in fact can vary considerably which affects every aspect of performance.
Yes as I guy that's 5'10" with a 30" inseam I agree! :)
I second Dean's agreement. I'm 6'1" with a 34" inseam.
@@jseski9209 as am I
@@jseski9209 6'3 with 34.5inseam lol
Does bike help to grow taller for 17 years old? Im 5ft10 and 225lbs fat i bought a bike for losing some weight and hoping for some growing because today i feel my knees hurts and i can't move right
But still if rider is 180 cm and weight about 60-65kg, can he earn some additional benefits?
200% risk of bone fracture in a crash lol
@@tianyigao5183 lol yes
you must be skinny af, lmfao i'm 1.65 and bigger than that
That background music makes it abit of a climb to watch the video
Great video once again - now you're teaching ppl how to dope in a video game lol
that'd be true if the smaller rider was on the taller person's bike, the fact that the smaller person quite sensibly buys a smaller bike probably negates that.
177 cm golden middle
Just a note regarding captions, you might want to upload your own, or speak more clearly/slowly.
@Yard Sale Daleyou mean eyes? 👀
Turn on automatic captions, first 5 seconds 😂
Had to rewind to double check. Very funny, will have to check other videos now!
Describes my dating strategy perfectly.
I often have trouble understanding those first few seconds of YT vids as most people do their introduction faster than normal speech. Now I know why I couldn't understand this one. 😂
Haha I need to rebrand the channel accordingly!
Good catch lol
Osteopath/ Ireland. Body Types. Anterior/posterior to a gravity line also needs to be in the equation Lower Lumbar Mechanics and pelvic brim dynamic in conjunction to this data Should be incorporated. Diet an nutritional information also. Enjoyed Vid 👍
in america 30% bmi is the new norm. I am around 20% and people are always categorizing me as too skinny.
Bmi or body fat percentage?
@@JakeHollibone I guess i meant to say body fat %.
I want a kona sutra, but not available for 6.5 ft person like myself
180 cm ,, and I 152 pounds or 69 kilos ,, That seems a bit light to me, or I am 25 pounds overwieght
The heights he was giving was with shoes on so 180 cm's or 5 ft 11 is probably 5 10 without shoes and that is the correct weight for that height. I'm that tall and weigh 150 and I'm not skin and bone so yeah you need to lose some weight.
Really interesting. I had a proper moan on Zwift riders the other day when the height doping was discovered! I’m tall and powerful(ish). But your explanation does make sense. I’ve always done well on long steady climbs, longer the better. Like Puig Major. And I naturally gravitated towards time trials when I got more into cycling
Speaking to the bone density Bob Roll once spoke about how back in his day guys didn’t break as many bones, and he thinks it’s the extreme weight cutting that is causing it. It could be all anecdotal, but if true could be explained by lack of bone density in the thinner riders who don’t cross train as much and specialize to the extreme.
It could also be due to a lifetime of drinking fluoridated water. It’s been proven that fluoride replaces calcium in enough quality to affect bones. Fluoride will actually increase a bones tensile strength, but also shows an increase in breaks.
That could be true if it was proven the people with breaks drank fluoridated water, as some I imagine have wells without (such as myself). Many outside large U.S. cities have well water without fluoride, but they all basically cut weight, train year round, and watch their weight to power.
It's not always about size and weight, it's about the intangibles like whom is willing to suffer more...
Not when you're 5'3" on a descent weighing 123lbs
He started teaching science
Anthropomorphic is the attribution of human traits to non-human entities. I think you meant morphological where morphology is the study of shape and structure. Other than that your conclusions have consigned me to a life riding uphill - i'm tall, if the converse to being a small rider on the flat receiving training stimulus out of the draft is a tall rider going uphill holds true (which sadly I expect it to).
Thank you for that well observed correction! Good luck with your riding and training!
Froome is 7% bodyfat? I've read he's more like 9-10%. He used to be 14% range before moving to Sky.
I'd say 5% when he won the tour last time
My age 1998 sir mere heights now 167 CM sir tell me 2 inches how to improve sir 🙏🙏🙏🙏🙏🙏🙏pls tell me sir
And if you are very short, your crank length will most likely be shorter than that of a tall rider. So does crank length have any effect on performance?
Another good question. Simple answer if you use your preferred crank length then power will be unaffected (ua-cam.com/video/Yl90KFqDW-Y/v-deo.html) in most cases. However if you go with super-short cranks you don't get enough muscle contraction range and if you go super-long you might run into close hip angle problems (hip angle will hopefully be in our forthcoming bike fit video).
@HazardousPleb V Indeed, people physiology can be very different from one person to another, yet people's minds are lazy - i.e. they constantly want to use shortcuts and apply simplistic rules. For me it's more of a "trial and error" thing and what is most confortable, and it shows in my numbers. It takes time and effort to experiment.
Amongst other problems of being very short could be wheel size and limitations on position because of it. Eg. Pozzovivo/many women racers etc?
I understand the corellations that has been demonstrated in the video, but in my view it still doesn't explain, why taller riders output more power. Is is the overall muscle mass? The greater mechanical leverage of long femurs? Wouldn't the choice of correct crank length and gears ratio close the gap? Or perhaps taller riders have grater blood volume, so it affects V2O. What about bigger frame taller riders require, so that some mass to the bike is added as well?
pafnucek I would think they would have more muscle and bigger lungs and etc to push out more energy.
Another, in my view even more important problem associated with low body fat mass than osteopenia is that steroid hormon production in the body ceases. The effect on muscle mass is that the damage generated through muscle overload in sports can no longer be repaired. The power reduces over time. This has been observed in the TdF when power was greatest at the beginning of the TdF and did not recover at all during rest days to reach low point by the end of the tour.
i think tall people have advantage in fact of leverage with longer legs....
if the bike is in proportion, i.e. the smaller rider quite sensibly buys a smaller bike then this advantage should be negated.
when considering metabolic cost to muscles and heart, my theory is that femur bone length (leverage) is not a factor for short-duration race performances.
I would think that for long-duration race performances, angular range at the hip, knee and ankle for a seated rider who is shorter, with cranks that are too long (say 170 rather than 160), leverage would have an adverse effect.
well if they are all riding the same bike whoever fit the bike would be the fastest. but . would say taller riders would have an overall advantage on the right bike. not only leverage but the ability to control the bike with smaller movements. basically taller rider has more range in the moment of inertia!
Guys im gonna be 16 in few days... And i haven't have the growth spurt! Does this mean i have stopped growing taller? Btw im 4.10
I would have thought shorter = more aerodynamic and less needed "structural" mass that is not contributing to power production.
Interesting video. What about ebikes? Thank you
My son is 6'4 at 17 years old
194cm
Sure there are freaks like Tom Dumoulin who are of average height, but he also has absurdly small bones for his size. This same pattern holds true for all endurance sports. Tom is average height, but there is nothing average about his bone mass, and therefore nothing average about his body mass as a function of height. Lean body mass per height has huge variations in humans, while trained heart and lung capacity are relatively constant regardless of body size.
Increasing your height does not increase power. The power in the legs and the velocity is a very big variable. Sometimes taller riders are NOT MORE powerful. Lean mass is also determined by teh individual not by size. The only thing that consistently is true is increase in mass. Which depending on the rider could be lean mass or not. A very short rider could ahve tremendously higher power than a taller rider. I have seen a shor bike rider lift the whole stack of weights in a gym, ( not a body builder, just a cyclist) whereas a taller rider COUD NOT. Power does not increase with size, nor does lean muscle.
For me it is still not intuitive. I mean if you just scale somebody then they have to have same ratio of weight,lean,fat,everything. So same w/kg and therefore they have to be same climbers. Just imagine some godzilla size giant, i really doubt you would beat him on the climb. And I really doubt some ant with an ant bicycle would be super fast on climb.
Bruv I'm 6.5 i ride a 65 cm frame
One thing is for certain. The tall guy will get laid more than the short guy. Chicks dig tall guys!
On a more serious note. It's seem's the taller rider has a greater mechanical advantage (i.e. longer femur).
Torque = Force X lever arm
Power = Torque (N-m) x cadence (radians/s), SI units N-m x radians/s = Watts
If torque is held constant, less force is needed for a longer lever arm. The taller rider can apply a smaller force to the pedal than a shorter rider to produce the same amount of power.
Another analogy should be familiar to automobile mechanics. If a nut is stuck you can use a cheater bar or an extension bar to a ratchet handle to loosen a stuck nut.
but the lever arm remains constant? It is the pedal after all. The only thing that can vary between riders is the force which they apply on the pedal.
Time to bike fast
Performance is spiritual. It can't be calculated.
You are definately on the wrong channel!
@@Fastfitnesstips The reason I say that is because there was a book that came out in the '90s I think about all this stuff where they concluded that sprinters had to be big. That was before Robbie McEwan and Mark Cavendish. Truly meaningful models are constructed after the event, in which case you don't need the model.
Thibaut Pinot is tall but fast on hills not on flats. There's no absolute rules
CALEB EWAN
Interesting.
Always thought my friend was short and had an advantage . bike was more compact and more efficient . I'm taller . but now you look at some of these pros and these pros that are all across-the-board ,, some are very big and muscular and some are very small light so I just think it's basically genetic gift and also training and determination.
Aerodynamics is a big factor .
Sir cycling height increase
I'm 58Kg and 181Cm. 20 years old. Is that weird? I do average on climbs, but do especially good at Hills. Not very good sprinter and not the greatest rider on the flat
Not weird at all just unusual! Keep cycling!
Who is more aerodynamic female or male?
Generally women because they are likely to be smaller (search male female 50th percentile) tall.life/wp-content/uploads/2013/04/HeightDistribution.jpg
Actually short and light riders have (huge) disadvantage
i forgot mark cavendish is 6'5 lol
It depends on many factors. Against wind, a skinny guy will probably lose to a more muscled guy in the same conditions. But in isolation, maybe the skinny will be faster.
I'm ‘5”9 and 210 pounds, and yes, they love to be behind me
This would be true if there wasn't a UCI regulation banning tall people from doing well in time trials
Ha! Interesting.
I'm 183cm and 70kg... and yes I can climb!
Does cycling really helps to increase height ?
I’m really small lol
And low weight
And you probably drop everyone on the climb too!
@@ILOVEDEFENDINGTHE1PERCENT out on the road yes
On zwift no
Hence why taller cyclists need 6.8 kg bikes which are becoming a joke. If you need to ride a 6.8 kg bike due to how small your body this is why cycling has been loosing viewers. I guarantee you if they all had to ride 10 kg bikes again viewers would come back. Weight is the key and 6.8 kg bikes does not make cycling as the prestige that it once was. This video mentions nothing on bike weight vs how tall the rider is.
I'm not tall but i climb
How height affects your cycling
Or it should be how cycling affects you height 😅😅
Doesn't a tall rider have to work harder on climbs and adapts so becomes a better climber? Conor Dunne announces his retirement. Thanks Prof.
"Freak of Nature" in sports, I don' t care what sport.....doping. Including Zwift.
Im 7ft tall very hard find bike and so expensive 😞😓😢😭
I would like to know if you have had any statistics run on any of your assumptions. Because to considering "theoretic" is very different when you run the numbers in reality against actual reality. What are your numbers , how many riders ahve you sampled ? I mean this needs to be checked against reality. I like the work you have done, but I don't see any statistical verification. Just assumptions based on " well if we believe this, then this must be tru. However this is not logic, this is a hypothetical against reality. Also i don't think Zwifts model is that accurate either. In that we agree on.
I'm 1,98m.
The music made me stop watching. Sorry. Too loud and annoying.
Tall riders have an inherent leverage advantage. The range of motion for a tall cyclist is far less than a short cyclist, and that range sits in the most powerful portion of leg extension. This is the reason shorter cranks are becoming popular, but now you've decreased your leverage of the pedal on the crank. Being a short cyclist sucks except when drafting.
Tall riders have a slight advantage because their bikes weigh less compared to their body weight.
If sat bolt upright you might be right. If you ride in a very aggressive position then no. Not nearly as much as the zwift model suggests.
@@TobiMcTobeface agreed!
Not much science in there. Lots of misinformation...
Looking forward to your corrections ML
Sounds like a load of rubbish to me did not get to the end. Body shape is the mane factor not body mass e.g. Narrow body or wide body with same mass narrow body moves through air with less resistance /height in is not the factor That's just for a start with out factors of muscle length and leg length