Bone-Breaking Skateboard Drops - What's the Biggest We Can Go?
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- เผยแพร่เมื่อ 14 ต.ค. 2024
- Really interesting question for today - what's the biggest drop a human body can endure and roll away? How high can you go before you break a bone, even with perfect technique? And how close are we to that number already? It's down to the inches!
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You really should start a Patreon. You put a lot of work into your videos, many of use would happily pitch in to help pay for all of your hard work.
After watching this I can't believe that Jamie Thomas made it down the leap of faith (18'8") without breaking anything!
That was gnarly
+VLSkate he must be a mutant!
VLSkate the board absorbed a lot of the impact.
Oh! VLSkate! Nice to see you here :)
I'm 42...ive skated since I was 13...never ollied anything even half the size jaws does...i have severe arthritis in my left hip..and I actually put that down to just pushing...i sometimes can't sleep because of it..trust me Jaws has it all to come!!..lets hope he keeps his money safe.
I respect the effort you put in brother
Respect to you for actually spending hours researching this stuff for us.
but also no respect for not going out and skating it, because it's just theory.
"If you have your own formulas ... I really don't wanna hear em"
Lmfaoooo
RadRat lowkey savage.
But my formula uses REAL HUMANS not dead people
This channel is straight fire
Thank you RadRat. This is good work and a true contribution to skateboarding.
You are my favorite channel at the moment rad rat !! Love your channel and content, hope you are doing well.
believe me, Jaws will not be able to walk when he gets to 40+ years old.
jim mc i don't think so... he can afford the best health care and with our advancements in medical technology might even prolong his career.
Jed Gabriel And yet Mullen is too banged up to get surgery for his fusing bones.
Jim, I believe in him more than I believe in you...
Sure he will because he isn't human.
*Technology
The perfect Rad Rat video, a little nerdy, very interesting, and just good! Keep it up man.
Wouldnt you need to account for the shock absorbing aspects of the skater's board and shoes? Landing on 4 wheels spreads out the shock.
Also speed too. dropping off of something going slow hurts way more than it does when you have speed.
I know this is an old video but appreciate the research and work that goes into these. Thanks for the great content
I don’t know if this is true but I feel that the skateboard takes some impact aswell, this is purely just from experience but I feel way less impact when I stick a trick and also you didn’t take into consideration for the impact taken by insoles, I can’t imagine it would be that much but it may all add up to a 30 stair being possible
I found this that may also back that up since shecklers kickflip was like 16ft he landed it on a board but this guy tries it on feet and brakes his ankle www.jenkemmag.com/home/2011/03/08/genius-breaks-his-ankle-in-honor-of-ryan-sheckler/
Ike Buttle yes the wheels, trucks, deck and shoes will help absorb/spread out the impact.
RadRat. You're such a badass man!!!! It's really great that you pour in so much time to try your hardest to make the closest accurate answer. There isn't too many people who would have spent six hours reading boring lectures and textbooks and websites from the 90's. Just to try and figure out a hypothetical question that a random subscriber asked. Truly ONE OF THE BEST CHANNELS ON TH-cam!!!!!
Thanks for all of your hard work!!
People have survived jumping out of planes without a parachute ( parachute malfunction). Yes it is miraculous they survived but the human body is a marvel that continues to defy science/logic. There always seems to be execptions that break the rules.
2 years late to the comment party, but to be fair while they did survive they usually break a lot of bones. You’re right though, there are freak incidents in nature.
You need to also take into account the impact that your skateboard absorbs(and also your insoles,shoes, socks, etc...). I have jumped down some stairsets and it hurts way more when you don't land on your board. So that might change the equation quite a bit. Loved the in-depth video, keep 'em coming dude!
People like Jaws being able to land from higher falls without getting injured could fall down to Wolff's Law. They jump off of things a lot, and over time strengthen the bones (and muscles) in their legs and feet.
C Hastings definitely. An experienced skater will be well above the “breaking point” of an average human. Even further if this average is taken from females as well as males
That's probably the best and most satisfying video about skateboarding :)
I love physics and I'm always trying to connect it with skating and figure out new tricks
love the way you tackle these problems, most people would do is calculate the date using cadavers and 'perfect' physics but that never works in real life so thank you for using a logical approach. always look forward to seeing your videos, great job
Subbed just for the effort put into this. Props!
As a math phd student, I think your work was pretty impressive! And, come on, you can admit that it was kinda fun ;)
The Leap of Faith that Jamie Thomas survived with both legs intact is supposedly 18-foot, 8-inch drop (according to wiki). And as Jamie said on the Nine Club, he believes Jaws could actually do it one day.
oxnardcore but it’s not skateble anymore :(
bovedli didn't they put in an elevator?
imagine how many wannabees would try it .....
Idk, if rollerbladers couldnt
I dont think a skateboarder can
@@ronny12301 maybe,but jaws isn't human.he could probably AT LEAST ollie it.
I think the speed you're going makes a huge difference, the impact is spread out over longer distance, like how BMX riders can jump El Toro without popping their tires. If I were trying to figure this out I'd look into what heights suicidal people can jump from and survive, then multiply how much easier the speed makes the impact feel. Even then, skateboarding doesn't always attract the most physically gifted people, if you were to take some Michael Phelps-type genetics character and have him strength train his legs for a few years, he would no doubt be able to survive better than the average suicidal jumper.
Great video man. The amount of work you put into it is insane. This is a criminally undersubscribed channel.
i missed the last 20 years of skating mate, back on my board at 42! Thanks for all your nerddy info research and excellent presentation. I'm catching up now!
one of your best videos my dude. excellent analysis
First, as a student of an academic subject, props on your research!
I don't think the MIT article was necessarily wrong to say 87 metres. You can ollie it, and survive. You'll just be calling your cruiser a skate-chair.
Also, you may prefer to just use google search for simple algebraic calculations such as the exponential Probability of injury. Symbolab is better for geometric and analytical calculations, it does the calculations with more convenient and clear notation and gives full steps for solutions.
And just for fun, would've been nice if you'd talked about how they'd gotten those cadavers
I bet people who sign up to be donors don't count on stuff like that happening looooool, I know I didn't.
I think what needs to be considered is the fact that the hypothetical skateboarder is not landing stationary, the fact that he/she rolls away accounts for a large amount of the shock experienced to be dissipated, this can be likened to some of the mind boggling gaps dropped by snowboarders (albeit landing on a non horizontal surface, however the overall mathematical/physical concept is the same)... So can we go bigger???
this is so incredibly well thought out, but i think there are way too many variables not considered for it to be "true"
consider the skateboard and its flexibility/shock absorption what with how the trucks are adjusted. I think the best way to do this would be to send cadavers on skateboards down increasingly large stairsets!
I really appreciate the effort behind this video. crazy mannn
Amazing work man
Haha, that was surprisingly fascinating. Thanks for doing that research, would have drove me crazy.
Fantastic video as always! Truly educational and interesting. Thank you for what you contribute to the skateboarding world!
Big ups for the amount effort you put into this
Speed has in fact no consequence on the impact of anything falling down in general. The thing is that if you skate a big gap and fall of your board, going fast will force your body to roll upon landing, which will distribute the impact on your whole body, so it will reduce the risk of injury.
Its not just human limit. As you do those crazy gaps over time, given you're given you're body enough nutrients to heal the damage, you'll create small fractures in the bones that heal and strengthen over their original strength. They also increase in density as they are subjected to load repeatedly. Its how power lifters get to the point they are able to. It also causes the ligaments to somewhat be able to withstand more load. Look into the amount of shearing forces exerted on the spinal column during deadlifting especially when they hit the point where its over 3x bodyweight lifts. Its absolutely insane. This area of study would help find a more relatable answer because most skaters hitting gaps these size are subjecting themselves to heavy impact regularly and training their body for it. It wouldn't be a ton higher than you already figured but it definitely would add some height. Then there's factors of the absorption of the wheels, deck and even bushings that should add a slight advantage over force of just your body hitting although its probably minimal at this point. Very interesting video, i would love to see more science in skating and this is right up that alley.
Jeff Stills back to board for radrat 😂
This is my new favorite channel. Keep it up!
You deserve a medal for this.
Just wow, thanks for this video! Very interesting and thought provoking.
Incredible! Ill ask again RadRat... where’s your Patreon? Take my money !
Brilliant, well done, look forward to the next one, keep up the good work.
You post so much great skate content. This was a really cool vid. Keep these up dude.
First of all nice job, and thank you for putting in so much work into these videos.
As a few people already said. There is a major thing you missed, and it's the forward momentum.
When Ali jumped the Lyon set and kicked his board out he injured himself immediately. And I think if you land on your feet (no board) you will injure yourself every time doing that. But the difference when Jaws did it was that he rolled of every time.
So the amount of newtons Jaws actually absorbs through his legs are prolly not close to the numbers used in injury calculations.
This just makes me think of future skateboard tricks like the "inward heelflip to broken leg." Rolling away without the injury doesn't count. Skate and destroy.
The amount of effort you out into these videos is amazing! Keep it up man! Also, I think it would be interesting if you researched, What material would make the perfect skate shoe, as in it not ripping ever.
Great video, I would say it's quite accurate. A few notes for viewers. The idea that distance/horizontal speed matters is only true if the surface you are landing on is not flat. The other way it would matter is with fluid related effects such as air resistance (e.g. airplanes landing). But when you ollie to flat, your speed only affects your ability to land due to board and wheel distortion. In the case here, we might assume a perfect skateboard and thus minimal effect if speed. But this would come into account in any non-ideal environment. At an extreme, picture doing an ollie into grass. It's tough to stay on your board because of the rolling force you must impart on your board.
As for the model of a skateboarder with perfect technique, we would need to assume they have the strength to decelerate in an ideal way to minimize impact on the legs. This would be a path that brings the center of gravity from full landing velocity to zero while minimizing the peak force on the skater. This would depend on the distance the center of gravity moves during deceleration, and thus the height of the skater. I would think that the ideal deceleration path is a constant deceleration from landing velocity at y=y0 to zero velocity at y=0, where y0 is the height of the center of gravity of the skater at first impact and the origin is the lowest the skater can get after landing.
The limit would be defined by the bones and joints including tendons (from muscles to bones) and ligaments (from bones to bones). The stress on the bones and joints would depend on the position the skater crouches into, and the weakest position would dictate the limit (as we assumed constant force due to constant deceleration). Another option would be to optimize the deceleration function based on the strength of the position the skater is in (crouched all the way would be weaker than crouched with knees not totally bent) but this is exceedingly complicated and assumes an inhuman ability to control one's landing. Since the best crouch is probably with the tibia vertical I would say the video does a great job of approximating all these factors.
Great video RR!! Keep up the good work!
What we would do without your work you put into these
What about the absorption that comes from trucks/shoes? I imagine you could add another 2 steps with some avenue trucks and a fresh pair of etnies.
Good JOB! i NEVER was so impressed by a youtuber. good research. good presentation! i hope youtube pays out for you, because you do an amazing job!
This was awesome Aron. This was a good follow up the I'd you can Ollie you can tre flip it question. People are always talking about the limits. Well there you go we are already breaking em as I would have thought. You just see that Lyon stair set and go no, nothing else. Like please nobody try anything bigger for fear of pure safety of life.
This video has inspired me to challenge the laws of physics. 5 meter drop, here I come.
Every video of yours is heavenly
Impressive how much work and thought you put into this! Very much worth it, interesting and enjoyable to watch as always. You just keep delivering quality content! :-)
Awesome video!! I bet shoes and the board help too
Great content aronl!
I was always told the bushings of the trucks had a lot to do with impact absorption. Also, it just seems like forward velocity play a role somehow? Awesome vid, great work.
Kevin P bushings have no effect on impact unless you land to one side, but that would probably make you fall (wheelbite, foot slips off, ect). a straight, centered landing puts force on truck hanger, which is touching the baseplate with the pivot thing (the metal piece of the hanger that goes into the pivot cup). hope that made sense
gunner murphy Right, but unless your axle is directly below that "pivot nub" I think at least some of your downward force will go to the kingpin area. The hanger is angled so all the force WON'T got straight into pivot cup... I think.
Wow, you definitely did your homework on this one! Great video!
Can you explain why the nose is bigger than the tail ? And why we can't buy symmetrical decks (nose and tail)?
Great show !
Regards from Chile!
I wonder how fresh those cadavers were. Bone isn't just like a rock inserted in our bodies but is living tissue. Living bone is much stronger than bone that's been drying out in the desert.
Your channel is unique and very well executed. Keep doing what you do! ;¬)
Yo, I live in Columbus, OH where that Motorist Building is! Love your channel, btw.
you wanna ollie off it, take one for the team ahah
im on my pc so lets put a longer comment : few years ago i ask a doctor how we can jump, after sending him the leap of faith and the lyon 25 five. He said it is already above the limit and they are like " super human " ( ok for jamie but boulala is just a no brain dude ).
For the physic thing : Speed mater too because when you jump of stairs you don't land straight vertical. Even without board, you can absorb more impact if you roll instead of staying on the same place with knee absorbtion ( i saw lot of people making huge gap like bercy 5 blocs ).
A skater in the air is more like a bullet with balistics and fall at 10m sec acceleration, with that you can math the impact and king of substract the speed with a vector.
And you need to add another variable to your "math", the hardware. When you look at jaw at the 25 his wheel was litterally eject of the truck while the nut stayed. The board need to be extra strong too. So naturally i got a question you can answer for your next video :
Is it better a strong board you can"t break but at a point it push up the force back into your body or a board who break and absorb the whole impact. And more your feet are close to edges, more you can have force up back to your whole body if the board is very strong. ( power ply talk :p )
You didn't factor in the fact that he's landing on a skateboard, which would change the numbers No? Also moving forward at a pace changes downward impact forces on the joints.
Gets cybernetic enhancements, jumps down 21 story building.
Big part of the energy from the impact burts into spinning wheels when you land.
"if you have your own formulas, I really dont wanna hear them" is so funny to me
This is good stuff but there is one main variable you forgot to consider. That is the forward momentum of the skater. The skater is being subjected to 2 vectors, acceleration due to gravity downward and his forward momentum. The faster the skater is travelling forward when he hits the ground on wheels the less downward impact he would endure. As scary as the Lyon 25 is imagine if the fifteen foot droop actually had no gap and it was attempted at a really slow speed. The downward impact would be huge and broken bones and boards would be certain,. So the heights a skater can Ollie from is also proportional to the speed he can generate as the forward momentum at impact significantly reduces the shock.
It’s worth noting that athletes typically have higher bone density, which equates to stronger bones. That’s really hard to capture in something like this, but it explains why pros can do greater heights than this.
Its tough because youd have to really factor in a huge part, speed. Speed is what redirects your momentum from vertical to horizontal, which is why parkour guys roll when they land, we do the same but with wheels...if your going fast enough and land at such an angle, you could do crazy shit
Final verdict/best skate setup for drops; 78a Ricta Clouds,
Avenue Suspension trucks
8.5 Powel Peralta Flight deck (stability and more room to land)
Double layered FP insoles
Nike AirMax shoes. (Lmao or some skate shoes but I would suspect the Cushing in AirMax to absorb landing)
I fucking love this channel
there's a bmxer who's jumped a tennis court fence I'm pretty sure but with bmx you can use the rear wheel as a fulcrum potentially raising the max height substantially.
REALLY GOOD VIDEO MAN
The approach of focusing on force is wrong because it is impossible to estimate the time of shock. It is better to consider Energy (mgz) loose or speed to evaluate an impact 1/2mv2). There are 2 concepts of shock : hard shock and smooth shock which is better because it allows to spread the energy absorption in everypart of the body which transforms it in heat of failure of part of the body. The best way to take shock is to be flexible but also to be lightweight to reduce the mgz or 0.5mv2 ! which is why jaws is good because he has both qualities.
Not gonna do a physic class here though.
btw nice topic pick sir !
please mind the faster you have to go to get over a certain distance (big stair set) the less force is centered vertically. imagine it like hopping a stone over water: the more speed it gets thrown with, the smoother is the impact on the water surface and the smaller is the angle. so more force is going in an other direction than downward.
I very much enjoyed this video
"Maybe school started somewhere on the planet", LOL!
Great research!
Respect for the amount of work you put in this video!
Although I’m pretty sure that the amount of speed you skate a drop with, is very important regarding impact force. When you skate a drop faster you hit the ground in a sharper angle wich results in more falling energy being converted into „moving forward“ energy. I‘m not 100% sure if this only applies for drops with incline landing. If somebody knows better, let me know ;)
makes sense, thanks ;)
Highest I ever jumped down was 8 feet it was so painful my ankle joints still crackle and pop, never again man!
gotta eat some raw veggies mate
It’s an interesting discussion.
Even a purely theoretical model would need to take into account a whole host of factors;
Anatomical - strength of bones, ligaments, tendons, muscles and other connective tissues as well as weight of rider (which would influence acceleration and impulse)
Biomechanical - the skaters ability to best utilise the anatomical factors
The skateboard itself - the deck, trucks, bushings, bearings and wheels will all absorb some amount of ground reaction force from the impact
Environmental - landing surface, air resistance (this would also include size and shape of the deck and body shape of the rider), even gravity varies around different locations on earth
in Estonia one dude on a scooter and another one on a skateboard both have done a 8m drop. the scooter dude broke his ankle but the skater barely bruised his leg and heel. so it is possible to go bigger if you bend your knees enough
Damn, nice video man!
Crashing a car is definitely not comparable to a skateboarder rolling at x amount of speed and ollieng a gap. The force on the impact of the landing of a skateboard isn't straight down. Some of it is spread out in the direction forward....parrallel to the ground.
Lmao. Like a baby punched your ankle. I don't know about you but that cracked me the fuck up.
jaws says he does good jumping down stuff from years of using a trampoline as a kid
You're forgetting forward momentum and angle of landing. That would increase that drastically. Vert???
You said that the distance travelled doesn't really factor in... but isn't your impact lessened if your momentum is moving forward? Rather than all of the force compressing your body from the top down, some of it is split diagonally if you are moving at speed right? And the longer the jump, the more speed you'll have when you clear it.
This was very informative and awesome to listen to! Who knew math could be useful for skating :D
Matthew Stenquist Math is useful for a lot of stuff if you want it to be :D
Very nice and explained very well. howe3ver, you missed the point of wheels landing and the space betweeen the wheels and your feet, there is some kinetic absorbsion in there., Also the change of kinectic force from a downward angle towards a latteral angle changes the force of the impact as well. So does the squeeze of your wheels, rubbers and shoe(insole). This all has to be factored in to the calculation of a skater dropping from a height. Please let me know what your thoughts are on this. Thanks for the videos, they're great!
Well researchrd! Thank you, brother.
Interesting video, but I think you may have left out a few variables. The urethane wheels, the sole of your shoes and the board will absorb some of that force.
mikey leblanc oiled a 40 stair on a snowboard so its definitely humanly possible to drop a from least that high. I think the real question is how much impact force your skateboard can take before it can no longer roll away. jaws is able to roll away without wheels, so I think it is probably up to ether trucks or bearings assuming you land perfectly
link to mikey leblanc gap: th-cam.com/video/hQseC1MWV9g/w-d-xo.html
Zachary Taylor point is skaters still have quite a bit of room before they hit the limit of human ability. I think jaws could maybe do a 30 stair
Don't forget that when moving forward some of the downward motion will be turned into forward motion
If you already said this i apologize. But what about the speed going forward? The faster you go forward will lesson the impact going down right?
go back to physics classes .... answer is NO
Yeah I was wondering this as well. And on top of that, impact on you body also depends on how long the collision lasts (that's the absorbing of the impact part). The longer you can make the time between the moment your wheels hit the ground and when your center weight point is the lowest, the less impactful it'll be on your body.
To actually give a better answer then people who quickly just say, "NO". You're forward velocity, in let's designate the 'x' direction, is separate from your velocity in the vertical, 'y', direction. That said, if you can transfer some of that downward energy into the x direction by how you position your body on landing, that would reduce the impact in the y direction. I can't think of an effective way to do that as any attempt to do so would likely send your board flying out from under you, as ideally you would land 'bolts' otherwise you would be unstable. As an aside, a landing ramp would have the effect I'm describing. Since a ramp is at an angle, part of the force will be directed in the x and y directions, making you ride a way much faster and feeling less impact than if you had landed on flat
But if your forward momentum is big enough, you won't hit the ground completely vertical. The direction of the total force of your body's momentum would be diagonal right? I mean, if you land on a ramp your angle towards the surface you're landing on (the ramp in this case) is less then 90 degrees, lessing the impact compared to the ramp not being there. So instead of your angle being this: | its this: \ (compared to your landing surface). But with enough forward momentum, by the time you'll land, the angle will also be \. Maybe I'm missing something here, but the effect should be the same: the impact will be less.
An airplane is able to land softly (despite being an incredibly heavy object coming down from something like 40,000 feet) because it is moving fast. Going fast decreases the amount of force that will refract into your feet from a fall (think angle of incident/angle of refraction)...so you could technically go stupidly big as long as you were going really really really fast (therefore parallel to the ground). Skydivers have even exploited this to do water landings without parachutes, which is suuuuuuuper gnarly but technically possible. The problem here now depends on how fast one can ollie, land, and stop (and how are you going to get going stupidly fast). But there is no one right answer here.
The math in the video generally refers to the force someone might endure jumping straight off something with no forward momentum, like a taildrop or a caveman off of something really huge.
RadRat when are you going to play Rocket Power Beach Bandits?!?!
the flex of the skateboard would help absorb some of the impact
I think you are seriously underestimating the strength of the human body and mind. We're only limited to the limits we put on ourselves. I highly doubt skaters of the past thought drops like the ones being done today were even possible.
I like to think that too but there is limits. Over years of skateboarding we're only gaining small inches in drop height. Same goes for any Olympic sporting events, shaving 1/ 100s of a second on the 100m. there's the dead zone . Drugs, body modifications and evolution will be the only way to make gains rolling away from drop heights.
What about the forward motion of a riding on a skateboard reducing the damage of the height of the stairset etc.
It would hurt less if you diagonally launch yourself down 25 stairs rather than going straight down as the force pushing you forward would basically be very primitive gliding.
P.S as your skateboard has wheels it would also absorb some of the impact as you are rolling and not going straight towards the ground, so technically there is no limit to how high you can ollie, you just would have to go very, very fast.
the wheels...bushings...deck...would all absorb some of the force
I'm not even talking about that, the speed you are going at would mostly neglect the force pushing you down, see how fast jaws was going at Lyon? For each meter of height you would need to go faster to create less direct impact, creating indirect impact, making it possible for ANY possible height to be ollied if you are going fast enough off it.
For sure....already said that
Same with jumping off a building. With the right amount of speeed...you could ollie "down" x meters and nothing would happen. You just have to be going fast enough
Studying physics....
Zachary Taylor See, I’ve been trying to figure this out too, because it does make sense. If a person jumps off a building and rolls, they absorb the impact better than if they didn’t roll, but I think this is because the impact is spread out over a greater period of time. When you’re going fast, you’re spreading the impact over a longer DISTANCE over the same period of time (i.e. the distance you travel between when your wheels hit the ground and when you finish bending your knees). This seems to make sense logically but I can’t think of any physical law that would actually agree with me so I must be wrong haha.
No matter what what horizontal component of velocity is vertical component just before landing will be the same in every scenario. If anything landing could be easier because angle at which you hit the ground would reduce making wheels absorb the impact. But then again how tall can you go before bearings being sort of fragille object can themselves together?
Every force has an equal opposite force. When you ollie something you don't come from zero horizontal motion. You have speed. As in your not just free falling. You are going forward with x amount of speed. When you land going forward still with the momentum you do have...there is a not just force in the direction downward...but forward. You have to factor that in. The force downward would be slighlty lessoned by the force (acceleration times mass right) going forward. There would be an force in the opposite direction you came from (horizontal to the ground) aka friction that would essentially slow you down on impact. This sad attempt at analyzing an ollie over a gap was just an analysis of the impact of someone standing still free falling straight down. That's not what an ollie down something is unless you lesson hasn't been learned by going slow down a stair set or whatever. This analysis also is completely off base because the deck...trucks...and wheels are all going to counteract the actual impact on your ankles and rest of your body. Again a failure in analysis...it wouldn't JUST be your ankle taking the impact. Our body has these things called knees....hips...vertabrae with cushions between them.
Zachary Taylor I agree that horizontal speed is not important for all of these calculations but I was rather trying to show that it can actually improve result in some way. I didn't make that assumption from physical stand point but rather from more practical knowledge. If you've ever done bigger stairs you should be familiar with rolling away from a jump. With smaller angle its easier to absorb impact when you roll it away than if you are falling straight down. My bad for not explaining what I meant.