Jumping kick issues?

[ralphmcpherson]

I don't practice jump spin kicks. Totally worthless in a SD scenario.

I agree they are worthless IF you view it as learning new kicks. I see them as drills to improve my effective kicks. Learning jumping and spinning kicks has taught me heaps about what my body can and cant do and about balance, hip rotation etc. These things have helped immensley in many other facets of my tkd. It also comes down to why someone is learning tkd in the first place. I ask all new students why they started tkd and less than 10% say "to learn how to fight", for many this a by product of why they have started but very rarely is it the main reason. So for many people the idea of not learning a kick because it "wont work on the street" doesnt make much sense.

 

[ralphmcpherson]

He is still in the air as the kick is being delivered. The fact that he allows his entire body mass to smash into the target before touching down and diverting all the energy into the target. As long as you are grounded there is still some energy left in the supporting leg.

Watch the Maui Thai guys kick. it is grounded and his foot slides along the ground ever so slightly. There is energy that is not transfered into the kick.

No we are not rockets and gravity slows down everything. As does friction. However the kick is still using the energy force provided by the muscles. removing the pulling force by jumping and kicking while at zero gravity (actually negative gravity while still going up) you enhance the speed and actually do speed up. Plus with the pull of gravity at impact your force is also increased.

But science aside, logic would only dictate that if jumping or spinning did not increase power or speed then why do it.

Lets look at Olympic javelin throwers. They run then hop while throwing. I would have to ask why.

Olympic shot put tossers as well. They spin then hop and toss. There is added power and speed that is created with the spin and the hop.

All good points. Why does a bowler in cricket run in from 30 metres away from the stumps? He may as well just stand at the crease and bowl, but Im sure without the run up he would not bowl at 150 klm/h.

 

[Cirdan]

Bad physics won`t make useless techniques more effective or functional.

In a flying kick there is only the air resistance that keeps you from bouncing off. A rooted supporting leg on the other hand provides so much friction it does not move at all, allowing the energy to be delivered to the target.

As dancingalone said we are not rockets, the leg is merely delivering a controlled push here. And to push you need..

 

[dancingalone]

He is still in the air as the kick is being delivered. The fact that he allows his entire body mass to smash into the target before touching down and diverting all the energy into the target. As long as you are grounded there is still some energy left in the supporting leg.

Well, sure. I've already conceded jumping MAY allow you to move more of your mass into the kick if your technique is good. And mass is indeed one component of power, but it cannot be the only factor considered in isolation.

But do you see the point I am making? Foster's kick was devastating because it is an advanced manifestation of 'normal' technique. He is not jumping up, spinning 180 degrees, and then kicking. Notice also that he didn't pick the jump spinning back kick or the flying side kick for his attempt when he had the entire universe of kicks available to him per the scenario. Instead he went with the humble back leg roundhouse kick.

No we are not rockets and gravity slows down everything. As does friction. However the kick is still using the energy force provided by the muscles. removing the pulling force by jumping and kicking while at zero gravity (actually negative gravity while still going up) you enhance the speed and actually do speed up. Plus with the pull of gravity at impact your force is also increased.

I'm not convinced. I think the physics involved is considerably more complex with things like drag and propulsion and acceleration forces unaccounted. Also, the various kicks have different directional flow (rotation direction and force) which have to be considered as well, i.e. is an aerial 180 degree kick as powerful as its grounded cousin vs. the different comparison of a 360 or even a reverse 180 from the back side. Human muscle groups are distinct after all - it's not the same level of complexity as an abstract problem like shooting something straight up in the air and then measuring its rate of descent.

But science aside, logic would only dictate that if jumping or spinning did not increase power or speed then why do it.

Lets look at Olympic javelin throwers. They run then hop while throwing. I would have to ask why.

Olympic shot put tossers as well. They spin then hop and toss. There is added power and speed that is created with the spin and the hop.

They are projecting an object out of their hands much like a catapult does. They are building up momentum which will help with the velocity of the much smaller object which is leaving their hand. A somewhat different premise than using the muscles in the legs to launch and propel the entire body both UP and OUT towards a target, I would think.

I play tennis at a high level. When you turn on the tv and watch players serving the ball to start the point, it can look like they are jumping at the ball. They are not. They are initiating a kinetic chain from bending and then uncoiling their knees and then turning their hips, waists, and shoulders along with some wrist pronation. Like Bren Foster's kick above, the power from their natural motion carries them into the air, not because they thought deliberately jumping up was a good idea.

I know I'm not going to convince you, ATC, but I would suggest to anyone who is interested in discovering the power of jump kicks for themselves to take my suggested trial. Get a good kicker around your same size. Actually, even someone a bit smaller than you should be fine too since we're seeking to prove the idea that a jumping kick is powerful. Set up in a front stance without the back leg locked with a kicking shield in hand. Have the kicker take a running start and let them kick your shield with the intention to blast you if they can. Time yourself and when their kick is arriving, stick your front stance with your own hip power and thrust the shield against the kick with both arms. I know that when I have tried this, I have knocked back the kicker every time and yes, we can kick a bit.

 

[ATC]

I know I'm not going to convince you, ATC, but I would suggest to anyone who is interested in discovering the power of jump kicks for themselves to take my suggested trial. Get a good kicker around your same size. Actually, even someone a bit smaller than you should be fine too since we're seeking to prove the idea that a jumping kick is powerful. Set up in a front stance without the back leg locked with a kicking shield in hand. Have the kicker take a running start and let them kick your shield with the intention to blast you if they can. Time yourself and when their kick is arriving, stick your front stance with your own hip power and thrust the shield against the kick with both arms. I know that when I have tried this, I have knocked back the kicker every time and yes, we can kick a bit.

No not convinced. When doing jump or jump spinning kicks the kicker is not just jumping for the sake of jumping and without the jump serving a purpose. They are in fact jumping to do just what you mentioned in your tennis reference. They are jumping to add power to the kick. Based on your theory of natural motion carrying them into the air they simply take it to the next natural level by deliberately jumping at the correct time with the correct technique to increase the power. By adding the momentum of the spin with the jump the power in increase even more.

As for you experiment, it is flawed. The reason you cannot push back the grounded side kick vs. the jump side kick is not because the grounded kicker is hitting or delivering more force but simply that there is nothing stopping the jump kickers recoil off of the target. The energy you used to push back is allowed to continue moving back the kicker. Vs. the energy used to push back the grounded kicker is rebounded off the ground and back into you, due to the grounded kicker being a part of the mass of the floor or the world. Pushing back only 200 pounds vs. how much the world weighs is what you are doing.

You are not measuring the force of either kick you are simply pushing back weight. With one being in the air and the other being a connected to the earth being the difference. The only true test would be to measure the kicking force with some equipment.

Also there are a few other things at play. Force impact vs. force to mass velocity ratio. Just like in the video the TKD guy hit harder and faster but his mass to velocity ration was less than the Capoeira guy. Meaning that the Capoeira kick was actually harder at a slower speed. The same kinetic linking was at play but the spinning of the capoeira increased the kicking power. The problem is that he did not spin and kick as fast as the TKD guy. If he could have matched the same speed he would have surpassed the force impact of the TKD guy.

Had the TKD guy done a tornado kick the power (force) would have also increased to mass and velocity. Maybe the kicking speed would have slowed but the force to mass and velocity would have increased.

As for why one kick vs. another chosen by the TKD guy? I can only guess. Not enough room on the platform maybe, again only a guess.

The one thing I will agree with you on it that the level of accuracy will drop when doing jump or spin kicks and if not done correctly with pin point accuracy the kick will lose power as it will miss or not direct all the power into the target. But that does not mean that more force is not possible but only the maximum force possible did not hit the target. Maybe another reason that the simple back leg round house was chosen. Also they may have been told that the next kick would be on a moving platform and he choose the most stable kick that he could do with power.

There is a second part to the clip where they moved (rocked or shook) the platform and then had the kickers kick again. All the kickers kicking powers drop drastically as they all had no balance with kicking and could not deliver all of the kicking power into the target.

 

[dancingalone]

No not convinced. When doing jump or jump spinning kicks the kicker is not just jumping for the sake of jumping and without the jump serving a purpose. They are in fact jumping to do just what you mentioned in your tennis reference. They are jumping to add power to the kick. Based on your theory of natural motion carrying them into the air they simply take it to the next natural level by deliberately jumping at the correct time with the correct technique to increase the power. By adding the momentum of the spin with the jump the power in increase even more.

Negative. The best reasons for executing jump kicks generally have to do with spectacle (they are cool looking), distance (a flying side kick can attack from a far way), or height (kicking a board held by someone standing on a chair for a demo).

Saying it is for power is a rather iffy proposition given the risk/reward factor. I reassert that anyone who can kick hard with a jumping kick could surely do just as well with less risk with a grounded version of the kick. It works out that way in pragmatic terms even though the idea of perfect mass conversion and awesome rotation speed from a jump and spin is appealing.

As for you experiment, it is flawed. The reason you cannot push back the grounded side kick vs. the jump side kick is not because the grounded kicker is hitting or delivering more force but simply that there is nothing stopping the jump kickers recoil off of the target. The energy you used to push back is allowed to continue moving back the kicker. Vs. the energy used to push back the grounded kicker is rebounded off the ground and back into you, due to the grounded kicker being a part of the mass of the floor or the world. Pushing back only 200 pounds vs. how much the world weighs is what you are doing.

You are not measuring the force of either kick you are simply pushing back weight. With one being in the air and the other being a connected to the earth being the difference. The only true test would be to measure the kicking force with some equipment.

How do you measure force without resistance being inherently part of the equation somehow? There used to be those force impact sensors sold in Black Belt magazine that supposedly measured how hard you were kicking and striking, but they inevitably depend on being placed on a support (like a heavy bag or a striking post) where you can then hit the sensor.

I submit that my kicking shield test is as good as anything that can be done inside a dojang, and it's worthy on practical terms. If we can by anecdotal experience take a kick from a step through side kick on a shield and say 'Good kick!', I see no reason the same standard for efficacy couldn't be used for a jumping version. Regardless of any aid from gravity, if the ultimate outcome is that a standing defender is able to repel easily a jumping kick, that says a lot about the usefulness of such a kick doesn't it? What good is it if it is so easily foiled? What kind of useful power is that?

Also there are a few other things at play. Force impact vs. force to mass velocity ratio. Just like in the video the TKD guy hit harder and faster but his mass to velocity ration was less than the Capoeira guy. Meaning that the Capoeira kick was actually harder at a slower speed. The same kinetic linking was at play but the spinning of the capoeira increased the kicking power. The problem is that he did not spin and kick as fast as the TKD guy. If he could have matched the same speed he would have surpassed the force impact of the TKD guy.

But that's the trade off. Kicking the way he did, the Capoeira guy cannot match the sheer speed of the standard roundhouse kick. This is similar to what I've been arguing about the flying side kick vs. the step through side kick. There is no way the speed of the flying kick matches the step through in real terms from start to finish. Even from chamber to hip turning over to heel thrusting out, if you prefer. You might gain some things from a jump side kick but useful, applicable power isn't one of them.

You have to also look at the bodies of the athletes in that video. Capoeira guy looked noticeably bigger and more muscular than Foster, so he probably had the mass advantage going in. I enjoy shows like Fight Science, but it's hard to make any real comparisons about technique differences without having exact clones for test subjects.

Had the TKD guy done a tornado kick the power (force) would have also increased to mass and velocity. Maybe the kicking speed would have slowed but the force to mass and velocity would have increased.

<shrugs> And there we have another trade off going. I don't particular care about crescent kicks myself, so I am not inclined to think about this kick further.

 

[ATC]

Negative. The best reasons for executing jump kicks generally have to do with spectacle (they are cool looking), distance (a flying side kick can attack from a far way), or height (kicking a board held by someone standing on a chair for a demo).

I am not talking about any demo kicks that are kicked way above the head. I am talking about kicks that can be used to defend or compete with.

Saying it is for power is a rather iffy proposition given the risk/reward factor. I reassert that anyone who can kick hard with a jumping kick could surely do just as well with less risk with a grounded version of the kick. It works out that way in pragmatic terms even though the idea of perfect mass conversion and awesome rotation speed from a jump and spin is appealing.

Not sure what you are saying here. I never said that a normal grounded direct type kick was not powerful. I only said that jumping or spinning kicks of the same nature as the equivalent grounded kicks hit with more force or power.

How do you measure force without resistance being inherently part of the equation somehow? There used to be those force impact sensors sold in Black Belt magazine that supposedly measured how hard you were kicking and striking, but they inevitably depend on being placed on a support (like a heavy bag or a striking post) where you can then hit the sensor.

Resistance of the target, yes.

I submit that my kicking shield test is as good as anything that can be done inside a dojang, and it's worthy on practical terms. If we can by anecdotal experience take a kick from a step through side kick on a shield and say 'Good kick!', I see no reason the same standard for efficacy couldn't be used for a jumping version. Regardless of any aid from gravity, if the ultimate outcome is that a standing defender is able to repel easily a jumping kick, that says a lot about the usefulness of such a kick doesn't it? What good is it if it is so easily foiled? What kind of useful power is that?

Still it is a flawed test as you are not measuring anything. Plus it is not being foiled at all. I can hold a shield and stop and baseball bat swing with it, even push against it. Take the shield away and I now fell the force and won't push against it even though I could.

But that's the trade off. Kicking the way he did, the Capoeira guy cannot match the sheer speed of the standard roundhouse kick. This is similar to what I've been arguing about the flying side kick vs. the step through side kick. There is no way the speed of the flying kick matches the step through in real terms from start to finish. Even from chamber to hip turning over to heel thrusting out, if you prefer. You might gain some things from a jump side kick but useful, applicable power isn't one of them.

He hit harder relative to speed. Regardless of the speed used the force impact is still greater. This in itself explains how you add power to something without adding speed. You increase the amount of mass. He put more mass into a slower technique. Not sure how it gets any more cut and dry as this.

You have to also look at the bodies of the athletes in that video. Capoeira guy looked noticeably bigger and more muscular than Foster, so he probably had the mass advantage going in. I enjoy shows like Fight Science, but it's hard to make any real comparisons about technique differences without having exact clones for test subjects.

Now this we can agree on. I am with you here.

<shrugs> And there we have another trade off going. I don't particular care about crescent kicks myself, so I am not inclined to think about this kick further.

[/quote]
We do the tornado kick as a round house no crescent. We keep the hip turned over and hit with the instep not the crescent way. More power in it that way.

 

[dancingalone]

I am not talking about any demo kicks that are kicked way above the head. I am talking about kicks that can be used to defend or compete with.

I am talking about kicks that can be used to compete with. There. Fixed it for you. :angel:

Not sure what you are saying here. I never said that a normal grounded direct type kick was not powerful. I only said that jumping or spinning kicks of the same nature as the equivalent grounded kicks hit with more force or power.

I am saying in the (hate to use this phrase but it fits) real world, jump/spin kicks DON'T have more power than their grounded versions. We can throw around all the theories about centripetal force and all, but it just doesn't happen that way when things matter.

Still it is a flawed test as you are not measuring anything. Plus it is not being foiled at all. I can hold a shield and stop and baseball bat swing with it, even push against it. Take the shield away and I now fell the force and won't push against it even though I could.

No? I can't find it on Youtube, but if you follow baseball, you might remember that game when Chan Ho Park, a Korean pitcher in MLB at the time, threw a bean ball at a batter. The batter charged the mound, and Park with his previous TKD training tried to throw a 180 degree jumping roundhouse kick. The batter easily crashed into Park with his body and avoided the kick. The fight was ended by people rushing in to pull them apart but Park was at a clear disadvantage after making the ill-advised kick.

Here is a video of Chan Ho Park trying another aerial kick on another occasion. Park didn't connect with this one either. It is #6 on the video.

http://www.metacafe.com/watch/133074/top_ten_baseball_fights/

The point is with these stories is that yes I believe I could very well knock down a jumping kick even without a kicking shield in hand.

He hit harder relative to speed. Regardless of the speed used the force impact is still greater. This in itself explains how you add power to something without adding speed. You increase the amount of mass. He put more mass into a slower technique. Not sure how it gets any more cut and dry as this.

I was addressing these two sentences you wrote: "The problem is that he did not spin and kick as fast as the TKD guy. If he could have matched the same speed he would have surpassed the force impact of the TKD guy." He CANNOT add more speed to the kick. That is the point. It is a necessary trade off from kicking in this manner. So any discussion about what if more speed could be added is merely an egghead academic one.

We do the tornado kick as a round house no crescent. We keep the hip turned over and hit with the instep not the crescent way. More power in it that way.

OK. :ultracool

 

[ralphmcpherson]

I tested the theory again in class last night and for me (and it may be different for others), I could definetely break a lot more timber with a spinning hook than a normal grounded hook kick. I dont know the physics behind it but it was significantly stronger with the spin, the instant my heel connected with the timber the extra force was very apparant with the spinning version. I got the same result when testing the difference between tornado and grounded roundhouse. Saying that spins/jumps are added purely for "asthetic value" just doesnt make any sense to me. Im definetely not talking about "street effectiveness", just sheer power.

 

[ATC]

...Im definetely not talking about "street effectiveness", just sheer power.

Exactly my point.

 

[dancingalone]

And my point was that jump kicks aren't powerful in real terms. It's a meaningless statement to claim they are more powerful if they cannot be applied in practical circumstances.

Regardless of any aid from gravity, if the ultimate outcome is that a standing defender is able to repel easily a jumping kick, that says a lot about the usefulness of such a kick doesn't it? What good is it if it is so easily foiled? What kind of useful power is that?

But since I am repeating myself, it might be time to stop now.

 

[ralphmcpherson]

And my point was that jump kicks aren't powerful in real terms. It's a meaningless statement to claim they are more powerful if they cannot be applied in practical circumstances.



But since I am repeating myself, it might be time to stop now.

I think that its hard to ever say that any kick "cannot be applied in practical circumstances". I have seen someone knocked out in a "real fight" with a spinning hook kick, and I havent seen a great deal of real fights. Fair enough, it wouldnt happen often but as you've probably seen from my previous posts on many threads I dont believe any kicks are "impractical". If Im mucking around fighting one of my non martial arts mates I guarantee I could connect with a spinning or jumping kick within 30 secs, and Im far from a great tkdist.

 

[Cirdan]

I think that its hard to ever say that any kick "cannot be applied in practical circumstances". I have seen someone knocked out in a "real fight" with a spinning hook kick, and I havent seen a great deal of real fights. Fair enough, it wouldnt happen often but as you've probably seen from my previous posts on many threads I dont believe any kicks are "impractical". If Im mucking around fighting one of my non martial arts mates I guarantee I could connect with a spinning or jumping kick within 30 secs, and Im far from a great tkdist.

Given a minute I could connect with a tornado punch to the ankle or a flying head butt to the bottocks too. Doesn`t mean it has any value in combat.

 

[ATC]

And my point was that jump kicks aren't powerful in real terms. It's a meaningless statement to claim they are more powerful if they cannot be applied in practical circumstances.

That can be the case for any kick or punch for that matter. Landing anything is a matter of ones own ability. Some can setup and land any kick. Some could not land the most basic of kicks. My only statement was that spin and jump kicks produce more power if performed correctly vs. the standard base kick.

Just saying.

 

[ATC]

Given a minute I could connect with a tornado punch to the ankle or a flying head butt to the bottocks too. Doesn`t mean it has any value in combat.

Really!? That's cool.

 

[Cirdan]

Really!? That's cool.

Yeah, sometimes I`ll finish with a tombstone piledriver too!

 

[ralphmcpherson]

That can be the case for any kick or punch for that matter. Landing anything is a matter of ones own ability. Some can setup and land any kick. Some could not land the most basic of kicks. My only statement was that spin and jump kicks produce more power if performed correctly vs. the standard base kick.

Just saying.

So true. Im sure if I got into a 'real fight' with someone like bren foster he could demonstrate very quickly why spinning/jumping kicks are not impractical (hopefully he would also get me to medical help as quickly as possible also).The point is, it come down to the skill level of the person involved, saying kicks are impractical is just too broad a generalisation.

 

[zDom]

I could make all sorts of arguments about why certain pitching techniques are better or worse based on my experiments but what does that really matter if I'm a poor pitcher who can't break 70 mph? All I can prove is what works best for someone with my poor ability and training.


Being in the air eliminates all friction from the supporting foot &#8211; this is an improvement on acceleration (F = M*A).

As for pushing from the grounded foot, keep increasing that push until there is so much PUSH that you are in fact launching the mass into the target.

I don't know physics well enough to explain it, but I wish I could demonstrate for you.

If I increase my power on a back leg round house kick, based on the "fold" of the bag I eventually top out power until I commit so much rotational and muscular force into the kick that I am leaving the ground just before impact, putting more of my mass into to the target.

If find it works the same with with side kick: eventually I kick so hard that my supporting foot leaves the ground as my body is launched into the air behind the kick.

Likewise I find jump spinning heel kicks and jump spinning hook kicks deliver more force &#8212; more acceleration, presumably, and more mass into the target (again, F=M*A)

But I watch lower belts or even other black belts with less refined technique attempt the same things and, as you have observed, generate less power.

 

[ETinCYQX]

I know for me, my spinning hook kick is way more powerful than my hook kick. Also much faster and cleaner. Still working the Tornado kick, but my roundhouse is an exceptionally powerful kick for me so I'd doubt it would have much more power. My hook is a more "precision" kick used for a close headshot.

EDIT: When I have time I'll play with some of my college's fancy physics toys and try and determine some speeds and some ratios. Could be fun.

 

[ralphmcpherson]

I know for me, my spinning hook kick is way more powerful than my hook kick. Also much faster and cleaner. Still working the Tornado kick, but my roundhouse is an exceptionally powerful kick for me so I'd doubt it would have much more power. My hook is a more "precision" kick used for a close headshot.

EDIT: When I have time I'll play with some of my college's fancy physics toys and try and determine some speeds and some ratios. Could be fun.

It would be interesting to hear the results if you do some experimenting. I experimented but without all the physics gadgets and spinning/jumping kicks were significantly more powerful, particularly spinning hook and tornado.