9 ms·

Limits to running speed in dogs, horses and human

67 points by fforflo 2y ago

deleted 2y ago
[deleted]
stonethrowaway 2y ago
I don’t think the title is accurate. And this isn’t about biology. The biology is there and the author dismisses it in Introduction and proceeds to go down the statistics rabbit hole. A golden opportunity to discuss how we can obtain limits of locomotion while adhering to thermodynamics was lost. There’s no physiology in here. Instead, we have plots of past competitions and silly predictions to go along with it. I suppose I’m asking too much of the author to write the “Tire & Vehicle Dynamics” book applied to the human body but, one can dream I suppose.
- Mathnerd314 2y ago
  Yeah, I was hoping for something building on this kind of work: https://simtk.org/projects/runningsim https://simtk.org/projects/runningsim There is definitely a speed at which your muscles would have to exert more force than bones/tendons can handle, for example. And then there is probably a muscle/weight tradeoff.
  - BobaFloutist 2y ago
    > And then there is probably a muscle/weight tradeoff For sprinting I don't know that there is, given that muscles are capable of exerting more force than their weight.
  - AlbertCory 2y ago
    if you're a data guy, then that's what you do. If there are absolute limits, they are probably in the ligaments. See my answer above about baseball pitchers.
    - Someone 2y ago
      > If there are absolute limits, they are probably in the ligaments. Maybe. https://en.wikipedia.org/wiki/Ulnar_collateral_ligament_reconstruction#Misconceptions https://en.wikipedia.org/wiki/Ulnar_collateral_ligament_reco...: “Some baseball pitchers believe that they can throw harder after ulnar collateral ligament reconstruction than they did beforehand. As a result, orthopedic surgeons have reported that parents of young pitchers have asked them to perform the procedure on their uninjured sons in the hope that it will increase performance. However, many people, including Frank Jobe, believe that any postsurgical increases in performance are most likely the result of the increased stability of the elbow joint and pitchers' increased attention to their fitness and conditioning. Jobe believed that rather than allowing pitchers to gain speed, the surgery and rehab protocols merely allow pitchers to return to their pre-injury levels of performance.” (I don’t see that header “misconceptions” follow from that paragraph, which says “some people believe A, others believe not-A”) Also, even if ligaments can’t be trained to be stronger and can’t be replaced by something stronger, longer arms should lead to faster throws for the same forces on those ligaments, wouldn’t it?
      - AlbertCory 2y ago
        well, there's always surgery, isn't there? Bionic pitchers. Longer arms: maybe. The tallest pitchers aren't the fastest, though. And there will probably never be a human with a 10 foot wingspan. There have always been pitchers with unhittable fastballs, but often they can't control them and they walk too many batters.
wongarsu 2y ago
Looking at <100 years of data, fitting a logistic equation to it and concluding that the limit is close to the current plateau is ... unsatisfying. Maybe that's an unfair summary, there is more statistic rigor than that in the paper. But nonetheless the observed time period seems way too small to support any conclusion
- Aachen 2y ago
  I was similarly wondering whether the author has tried taking a subset of the data and seeing if the result still comes out the same. It seems mildly suspect that, in each case, it just so happens that we've just about reached the limit. By excluding recent data, there can't be a bias to recent values
- hansvm 2y ago
  It depends a bit on your model of the observed performance improvements. Do we have better training and nutrition (a logistic model seems simplistic if so)? Do we simply perform better when we have other high-performing peers to compete against (in which case the logistic model isn't perfect, but it's not terrible -- you'd expect an exponential increase in population to have enough additional brackets to get every constant, additive gain, and assuming logistic growth for the population a logistic curve-fitting roughly inverts that function)? At best though, it's a model of what _will_ be achieved, as opposed to the hypothetical bounds on those achievements if we were going to invest resources into hitting them.
- PaulDavisThe1st 2y ago
  What it incredibly frustrating to me that is on the one hand, we might somewhat glibly say that we know we can ignore the data for the preceding 5000 years because we know that all the fastest performances have been in the last century. But merely saying that then leads to the question: do we actually know that? And what's frustrating is that I don't there is any way to be confident about any answer to that question.
  - scott_w 2y ago
    I think we can. We have archeological records showing us what even the fittest people looked like and what clothes they wore. Modern equipment is so much better than what ancient people had access to, it’s just not even close. Better nutrition means people can get bigger/stronger more easily. Easier access to training equipment amplifies this. The access to information we have means even more people can train more optimally than people in the past possibly could. The sheer volume of people gives us statistical probability that genetic freaks will appear more frequently. All of these gives us more confidence that current records are “true” records.
Aachen 2y ago
The to-me coolest bit is at the very bottom, captioned "context": > [...] a women running the estimated absolute fastest speed for 100 m would have beaten the world's fastest male in 1955, a feat that would have astounded contemporary spectators. The predicted maximum speed (5.83 m s–1) for a man running a marathon (42.2 km) would have been fast enough to beat the great Emil Zatopek in his world's best 10 km race in 1954. Those in the stands watching that race could not have imagined someone besting Zatopek by 16 s, and then simply continuing at that winning pace for another 32.2 km. The actual result for humans is split out by distance and gender in figure 11 near the bottom, peaking at ~150m distance just shy of 11 for men and 10 m/s for women
- polishdude20 2y ago
  I wonder if we have better/faster athletes now because poverty is going down? Like, back in the 1950's there were people on this earth who were genetically the best at running but potentially did not have the economic means to actually train themselves and develop. As we bring more people above the poverty line, there's more of a chance of finding those genetically gifted people and developing them.
  - hacb 2y ago
    The technology related to running also improved a lot in the last years (running shoes with carbon inserts, better nutrition, ...)
  - K0balt 2y ago
    I’d conjecture that what we see with both humans and animals is a result of two primary factors: nutrition and global mobility. Better food and medicine combined with mobility so that the best of the best can be brought to the competition.
  - wiether 2y ago
    There are dozens factors that explains the performance improvements, like tech that can help detect future talents, globalization that can help finding talents in the middle of nowhere, studies on physiology... The biggest one being probably : experience. Thousands of athletes and coaches have learn for other's success and failures regarding training, pacing, resting, nutrition and removal of psychological limitations. Roger Bannister history is relevant : before he broke the 4mn mile, people thought it was impossible for decades. Once he did, many other achieved the same feat in the following years. Regarding your question about poverty, I'd say it's a tough one. Because in third World countries, only the athletes that pass the selection process actually come out of poverty. The others stay there. In rich countries on the other hand, I see two things : - having the means to train with the best coaches, the best gear... can help you make it to the top ; some rich parents are even pushing hard this way (see the article on tennis a few weeks back here en HN) - but also, if you have the means to go to college, aiming for a regular career is a way much safer bet than pursuing a professional athlete career. Teenagers that are very good at a sport and are given the choice between the two, most are going to pick the regular career and enjoy sport outside of work. A poor kid who's choice is between a life changing career in sports and stay in the misery they known since their birth, are definitely going to pick the only one offering the hope of a positive outcome.
joaomacp 2y ago
Obligatory related paper: "in the future, the fastest humans on the planet might be a quadrupedal runner at the 2048 Olympics, which may be achieved by shifting up to the rotary gallop and taking longer strides with wide sagittal trunk motion." https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4928019/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4928019/
- ptsneves 2y ago
  Today I learned there is such a thing as human quadrupedal rubbing. https://youtu.be/RZlvWpeC208?si=xsii66h2cPtjH6ba https://youtu.be/RZlvWpeC208?si=xsii66h2cPtjH6ba
  - jacobolus 2y ago
    15.7 seconds to run 100 meters on all fours is pretty impressive, https://www.youtube.com/watch?v=F3h0AkNNP70 https://www.youtube.com/watch?v=F3h0AkNNP70 Seems like it would be hard on the wrists.
jijojohnxx 2y ago
Interesting perspective!
mark-r 2y ago
Interesting fact: humans are well built for shedding excess heat, which is a limiting factor in long races. It is possible under the right weather conditions for a man to outrun a horse.
- spacecadet 2y ago
  I am not a researcher here, but I have read that some believe this contributed to early human success, as it allowed humans to essentially run down their prey over long distances. For instance, as a bow hunter, I have observed how short distance a deer can actually flat out run before what appears to be lack of "something", not lack of fear. That something being energy or physical constraints of some kind. I am also a long distance runner with ultra marathons under my belt and I believe that humans are great at sustained long distance. Anything can sprint fast for a short distance, but it requires a unique combination of human qualities to sustain medium speed over great distances.
  - paganel 2y ago
    Since I’ve started owning dogs I’ve realized how much of an advantage we, humans, have as a species because we can sweat and hence regulate our temperature through almost all of our body, while on the other hand dogs can only do that through their tongues (afaik).
    - dredmorbius 2y ago
      Dogs have a higher surface-area-to-volume ratio, which helps, though the fur of course hinders. On a related note, I've speculated for years that tongues play a major cooling role for whales. These are highly vascularised structures which can be exposed to tremendous water flows (for effective thermal transfer). The animals otherwise have an immense metabolism, and are largely quite well insulated by blubber. And of course cannot effectively sweat. Even if the usual problem is heat retention, highly-energetic activities (long-distance migration, escape from or combat with predators, feeding activities) might result in excess heat which needs to be shed quickly. As a long-time swimmer myself I've experienced overheating even in relatively cool waters (for humans) and the challenges in reducing core temps. There have been multiple cases of open-water swimmers overheating and even dying swimming in warm temperatures (several in the middle-east over the past decade or so). I'd just written that I'd found no scientific literature discussing this when I attempted another search (using FastGPT from Kagi, which I'm finding quite useful for this sort of thing). And lo! Two hits: "Thermoregulation in the mouths of feeding gray whales" (1997) <https://pubmed.ncbi.nlm.nih.gov/9353198/ https://pubmed.ncbi.nlm.nih.gov/9353198/> doi: 10.1126/science.278.5340.1138. "The blood vessel network in the tongues of gray whales precools blood to avoid heat loss via counter-current heat exchange." <https://asknature.org/strategy/lingual-rete-precools-blood/ https://asknature.org/strategy/lingual-rete-precools-blood/> This actually discusses structures of the tongue which reduce thermal transfer, but also specifically addresses the characteristics of the tongue which make it effective at thermal transfer: Baleen whales such as the gray whale move huge quantities of cold ocean water through their very large mouths and across the filtering surface of the baleen. The tongue of a whale can represent as much as 5% of its total body surface area. The whale’s body is well insulated with blubber but not the tongue. Thus, to avoid losing too much of its body heat to the cold water passing through its mouth, the gray whale’s tongue has the largest counter-current heat exchanger yet described. I feel vindicated!
lupire 2y ago
The host website is as interesting as the article: http://biologists.com http://biologists.com
Glyptodon 2y ago
I was hoping this would be a more mechanical/physics defined limit. Along the lines of "given bone shapes and mass, muscle mass, maximum twitch speed, and energy expenditure, we determined the maximum performance combinations and their physical limits."
- 082349872349872 2y ago
  Let's say we have a 100 kg sprinter capable of anaerobically producing 20 watt/kg for up to 10s. How fast could they reach 100 m from a standing start, in a vacuum, with perfect traction? Having forgotten how to set up simple integrals, I've consulted the interwebs, which claim d = (8*P/9*m)^1/2 * t^3/2 Assuming I can still do algebra, that's t = (d / (8P/9m)^1/2)^2/3 ~= a little over 8 sec ? Lagniappe: https://www.youtube.com/watch?v=-Zd-70dCstI&t=55s https://www.youtube.com/watch?v=-Zd-70dCstI&t=55s
  - deleted 2y ago
    [deleted]
  - deleted 2y ago
    [deleted]
  - 082349872349872 2y ago
    without androgens, that'd be 15 watt/kg for 9 sec. unless you're a horse, in which case without androgens, with wind resistance and less than perfect traction, while carrying a 57kg human, it's possible to do 101m in 6,67 sec. https://www.youtube.com/watch?v=86isg0zNpi8&t=80s https://www.youtube.com/watch?v=86isg0zNpi8&t=80s
interludead 2y ago
Have you ever had the chance to see a Greyhound in real life? They are so beautiful.

67 points by fforflo 2y ago

deleted 2y ago

[deleted]

I don’t think the title is accurate. And this isn’t about biology. The biology is there and the author dismisses it in Introduction and proceeds to go down the statistics rabbit hole. A golden opportunity to discuss how we can obtain limits of locomotion while adhering to thermodynamics was lost. There’s no physiology in here. Instead, we have plots of past competitions and silly predictions to go along with it. I suppose I’m asking too much of the author to write the “Tire & Vehicle Dynamics” book applied to the human body but, one can dream I suppose.

Mathnerd314 2y ago
Yeah, I was hoping for something building on this kind of work: https://simtk.org/projects/runningsim https://simtk.org/projects/runningsim There is definitely a speed at which your muscles would have to exert more force than bones/tendons can handle, for example. And then there is probably a muscle/weight tradeoff.
- BobaFloutist 2y ago
  > And then there is probably a muscle/weight tradeoff For sprinting I don't know that there is, given that muscles are capable of exerting more force than their weight.
- AlbertCory 2y ago
  if you're a data guy, then that's what you do. If there are absolute limits, they are probably in the ligaments. See my answer above about baseball pitchers.
  - Someone 2y ago
    > If there are absolute limits, they are probably in the ligaments. Maybe. https://en.wikipedia.org/wiki/Ulnar_collateral_ligament_reconstruction#Misconceptions https://en.wikipedia.org/wiki/Ulnar_collateral_ligament_reco...: “Some baseball pitchers believe that they can throw harder after ulnar collateral ligament reconstruction than they did beforehand. As a result, orthopedic surgeons have reported that parents of young pitchers have asked them to perform the procedure on their uninjured sons in the hope that it will increase performance. However, many people, including Frank Jobe, believe that any postsurgical increases in performance are most likely the result of the increased stability of the elbow joint and pitchers' increased attention to their fitness and conditioning. Jobe believed that rather than allowing pitchers to gain speed, the surgery and rehab protocols merely allow pitchers to return to their pre-injury levels of performance.” (I don’t see that header “misconceptions” follow from that paragraph, which says “some people believe A, others believe not-A”) Also, even if ligaments can’t be trained to be stronger and can’t be replaced by something stronger, longer arms should lead to faster throws for the same forces on those ligaments, wouldn’t it?
    - AlbertCory 2y ago
      well, there's always surgery, isn't there? Bionic pitchers. Longer arms: maybe. The tallest pitchers aren't the fastest, though. And there will probably never be a human with a 10 foot wingspan. There have always been pitchers with unhittable fastballs, but often they can't control them and they walk too many batters.

wongarsu 2y ago

Looking at <100 years of data, fitting a logistic equation to it and concluding that the limit is close to the current plateau is ... unsatisfying. Maybe that's an unfair summary, there is more statistic rigor than that in the paper. But nonetheless the observed time period seems way too small to support any conclusion

Aachen 2y ago
I was similarly wondering whether the author has tried taking a subset of the data and seeing if the result still comes out the same. It seems mildly suspect that, in each case, it just so happens that we've just about reached the limit. By excluding recent data, there can't be a bias to recent values
hansvm 2y ago
It depends a bit on your model of the observed performance improvements. Do we have better training and nutrition (a logistic model seems simplistic if so)? Do we simply perform better when we have other high-performing peers to compete against (in which case the logistic model isn't perfect, but it's not terrible -- you'd expect an exponential increase in population to have enough additional brackets to get every constant, additive gain, and assuming logistic growth for the population a logistic curve-fitting roughly inverts that function)? At best though, it's a model of what _will_ be achieved, as opposed to the hypothetical bounds on those achievements if we were going to invest resources into hitting them.
PaulDavisThe1st 2y ago
What it incredibly frustrating to me that is on the one hand, we might somewhat glibly say that we know we can ignore the data for the preceding 5000 years because we know that all the fastest performances have been in the last century. But merely saying that then leads to the question: do we actually know that? And what's frustrating is that I don't there is any way to be confident about any answer to that question.
- scott_w 2y ago
  I think we can. We have archeological records showing us what even the fittest people looked like and what clothes they wore. Modern equipment is so much better than what ancient people had access to, it’s just not even close. Better nutrition means people can get bigger/stronger more easily. Easier access to training equipment amplifies this. The access to information we have means even more people can train more optimally than people in the past possibly could. The sheer volume of people gives us statistical probability that genetic freaks will appear more frequently. All of these gives us more confidence that current records are “true” records.

Aachen 2y ago

The to-me coolest bit is at the very bottom, captioned "context": > [...] a women running the estimated absolute fastest speed for 100 m would have beaten the world's fastest male in 1955, a feat that would have astounded contemporary spectators. The predicted maximum speed (5.83 m s–1) for a man running a marathon (42.2 km) would have been fast enough to beat the great Emil Zatopek in his world's best 10 km race in 1954. Those in the stands watching that race could not have imagined someone besting Zatopek by 16 s, and then simply continuing at that winning pace for another 32.2 km. The actual result for humans is split out by distance and gender in figure 11 near the bottom, peaking at ~150m distance just shy of 11 for men and 10 m/s for women

polishdude20 2y ago
I wonder if we have better/faster athletes now because poverty is going down? Like, back in the 1950's there were people on this earth who were genetically the best at running but potentially did not have the economic means to actually train themselves and develop. As we bring more people above the poverty line, there's more of a chance of finding those genetically gifted people and developing them.
- hacb 2y ago
  The technology related to running also improved a lot in the last years (running shoes with carbon inserts, better nutrition, ...)
- K0balt 2y ago
  I’d conjecture that what we see with both humans and animals is a result of two primary factors: nutrition and global mobility. Better food and medicine combined with mobility so that the best of the best can be brought to the competition.
- wiether 2y ago
  There are dozens factors that explains the performance improvements, like tech that can help detect future talents, globalization that can help finding talents in the middle of nowhere, studies on physiology... The biggest one being probably : experience. Thousands of athletes and coaches have learn for other's success and failures regarding training, pacing, resting, nutrition and removal of psychological limitations. Roger Bannister history is relevant : before he broke the 4mn mile, people thought it was impossible for decades. Once he did, many other achieved the same feat in the following years. Regarding your question about poverty, I'd say it's a tough one. Because in third World countries, only the athletes that pass the selection process actually come out of poverty. The others stay there. In rich countries on the other hand, I see two things : - having the means to train with the best coaches, the best gear... can help you make it to the top ; some rich parents are even pushing hard this way (see the article on tennis a few weeks back here en HN) - but also, if you have the means to go to college, aiming for a regular career is a way much safer bet than pursuing a professional athlete career. Teenagers that are very good at a sport and are given the choice between the two, most are going to pick the regular career and enjoy sport outside of work. A poor kid who's choice is between a life changing career in sports and stay in the misery they known since their birth, are definitely going to pick the only one offering the hope of a positive outcome.

joaomacp 2y ago

Obligatory related paper: "in the future, the fastest humans on the planet might be a quadrupedal runner at the 2048 Olympics, which may be achieved by shifting up to the rotary gallop and taking longer strides with wide sagittal trunk motion." https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4928019/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4928019/

ptsneves 2y ago
Today I learned there is such a thing as human quadrupedal rubbing. https://youtu.be/RZlvWpeC208?si=xsii66h2cPtjH6ba https://youtu.be/RZlvWpeC208?si=xsii66h2cPtjH6ba
- jacobolus 2y ago
  15.7 seconds to run 100 meters on all fours is pretty impressive, https://www.youtube.com/watch?v=F3h0AkNNP70 https://www.youtube.com/watch?v=F3h0AkNNP70 Seems like it would be hard on the wrists.

jijojohnxx 2y ago

Interesting perspective!

mark-r 2y ago

Interesting fact: humans are well built for shedding excess heat, which is a limiting factor in long races. It is possible under the right weather conditions for a man to outrun a horse.

spacecadet 2y ago
I am not a researcher here, but I have read that some believe this contributed to early human success, as it allowed humans to essentially run down their prey over long distances. For instance, as a bow hunter, I have observed how short distance a deer can actually flat out run before what appears to be lack of "something", not lack of fear. That something being energy or physical constraints of some kind. I am also a long distance runner with ultra marathons under my belt and I believe that humans are great at sustained long distance. Anything can sprint fast for a short distance, but it requires a unique combination of human qualities to sustain medium speed over great distances.
- paganel 2y ago
  Since I’ve started owning dogs I’ve realized how much of an advantage we, humans, have as a species because we can sweat and hence regulate our temperature through almost all of our body, while on the other hand dogs can only do that through their tongues (afaik).
  - dredmorbius 2y ago
    Dogs have a higher surface-area-to-volume ratio, which helps, though the fur of course hinders. On a related note, I've speculated for years that tongues play a major cooling role for whales. These are highly vascularised structures which can be exposed to tremendous water flows (for effective thermal transfer). The animals otherwise have an immense metabolism, and are largely quite well insulated by blubber. And of course cannot effectively sweat. Even if the usual problem is heat retention, highly-energetic activities (long-distance migration, escape from or combat with predators, feeding activities) might result in excess heat which needs to be shed quickly. As a long-time swimmer myself I've experienced overheating even in relatively cool waters (for humans) and the challenges in reducing core temps. There have been multiple cases of open-water swimmers overheating and even dying swimming in warm temperatures (several in the middle-east over the past decade or so). I'd just written that I'd found no scientific literature discussing this when I attempted another search (using FastGPT from Kagi, which I'm finding quite useful for this sort of thing). And lo! Two hits: "Thermoregulation in the mouths of feeding gray whales" (1997) <https://pubmed.ncbi.nlm.nih.gov/9353198/ https://pubmed.ncbi.nlm.nih.gov/9353198/> doi: 10.1126/science.278.5340.1138. "The blood vessel network in the tongues of gray whales precools blood to avoid heat loss via counter-current heat exchange." <https://asknature.org/strategy/lingual-rete-precools-blood/ https://asknature.org/strategy/lingual-rete-precools-blood/> This actually discusses structures of the tongue which reduce thermal transfer, but also specifically addresses the characteristics of the tongue which make it effective at thermal transfer: Baleen whales such as the gray whale move huge quantities of cold ocean water through their very large mouths and across the filtering surface of the baleen. The tongue of a whale can represent as much as 5% of its total body surface area. The whale’s body is well insulated with blubber but not the tongue. Thus, to avoid losing too much of its body heat to the cold water passing through its mouth, the gray whale’s tongue has the largest counter-current heat exchanger yet described. I feel vindicated!

lupire 2y ago

The host website is as interesting as the article: http://biologists.com http://biologists.com

Glyptodon 2y ago

I was hoping this would be a more mechanical/physics defined limit. Along the lines of "given bone shapes and mass, muscle mass, maximum twitch speed, and energy expenditure, we determined the maximum performance combinations and their physical limits."

082349872349872 2y ago
Let's say we have a 100 kg sprinter capable of anaerobically producing 20 watt/kg for up to 10s. How fast could they reach 100 m from a standing start, in a vacuum, with perfect traction? Having forgotten how to set up simple integrals, I've consulted the interwebs, which claim d = (8*P/9*m)^1/2 * t^3/2 Assuming I can still do algebra, that's t = (d / (8P/9m)^1/2)^2/3 ~= a little over 8 sec ? Lagniappe: https://www.youtube.com/watch?v=-Zd-70dCstI&t=55s https://www.youtube.com/watch?v=-Zd-70dCstI&t=55s
- deleted 2y ago
  [deleted]
- deleted 2y ago
  [deleted]
- 082349872349872 2y ago
  without androgens, that'd be 15 watt/kg for 9 sec. unless you're a horse, in which case without androgens, with wind resistance and less than perfect traction, while carrying a 57kg human, it's possible to do 101m in 6,67 sec. https://www.youtube.com/watch?v=86isg0zNpi8&t=80s https://www.youtube.com/watch?v=86isg0zNpi8&t=80s

interludead 2y ago

Have you ever had the chance to see a Greyhound in real life? They are so beautiful.