The impact of a Kung Fu Shin Kick - aka oblique kick in MMA

[JowGaWolf]

I created a video to try to shed some light on the impact of this kick. It's difficult to imagine how devastating this kick actually is unless you get one by someone who can actually do one correctly. I didn't have any volunteers that wanted their knee kicked so I had to bring out the heavy bag, that I practiced on.

I'm not sure how much the heavy bag weighs so I'll have to get back to you on that one. I used the yellow tape that's on the floor so you could get an idea of the distance that the bag travels. I originally thought about having someone stand behind the bag to hold it in place but I didn't feel comfortable with the impact that it might have on the leg that would next to the bag supporting the bag.

Force of the Kick
I thought the picture above would be a good place to start in terms of talking about the mechanics of this kicks. The picture is a screen capture from the video that I recorded using my smartphone. The first step is to analyze the movement of this kick by looking at the blur in the picture. The blur helps to give an idea of the body parts involved in this kick. You can also see that I'm not stomping down on the bag by looking at the indentation of the bag. A downward stomp would have made the lower part of the bag crumple, but in the picture you can see the indentation on the lower part of the bag is smooth.

The force being placed on the bag is not pushing force it's striking force. The top part of the bag is not blurred which means there is no motion at the point of impact. I'm not not pushing, I'm kicking. In the post
Awesome Kung Fu Kick used in MMA I talk about how the impact of the kick feels to the shin and how it shoots the calf muscle off the bone. You can actually see the bag react in a similar manner. Look at the blur to the rear of the bag. This is the energy from the kick shooting out of the back of the bag. The bur that you see in the back of the bag is caused by the bag rapidly expanding from the force of the kick and then snapping back. There is no other blur on the back of the heavy bag at this point. I slowed the video down so that you can see this entire process.

Some have expressed doubt that there is enough force to break a knee. From experience of receiving a kick like this to the shin. I can only assume that energy from the kick will shoot out the back of the knee in a similar manner that it shot out the back of this bag.

Technique of the Kick
The technique that I used for this kick is one that would be used if I was trying to break the knee, which means that I'll push through until something gives and then continue to push through after it gives. My goal was to follow through as much a possible without creating bad form and over extension. I had to kick lower than the knee for the purpose of the video. I was concern that if I kicked the bag too high up that it would fall over when I kick the bag. Then I would have to read the nonsense about how the kick worked on the bag because I kicked high up on the bag. My goal was to kick low enough to where the bag would slide across the floor instead of falling towards me from kicking too low and falling backwards from kicking too high. I was able to get that on the first try, which made me happy because I really didn't want to be at the school all day trying to make that happen. I was a little sloppy in the photo. My heel should not come off the ground as shown in the photo. F

Form vs application
The form version of this kick often looks useless and weak, but it teaches the proper mechanics that are required to make this an effective kick when done as an application. Unfortunately I've seen some really bad demos of this and I currently have a student who has messed up knees because she kicked with bad technique. Application of this can easily be done while in fighting stance and it's a really fast kick. The wind up of this kick is only because I tried to get a good video of the technique from beginning to end.

Here is the video enjoy it while you can

I would like to hear your opinions or questions about this kick. Let me know if you think this kick has enough power to break bone or at the least break a knee.

 

[KangTsai]

I tried the kick in the air (and I hope it looks "correct"). From what I feel, the movement is a quick twist of the kicking hip outward, with a slight lift of the leg. I don't see how you could strain from this kick. As for the power — hell yeah it can take out a knee.

 

[JowGaWolf]

I tried the kick in the air (and I hope it looks "correct"). From what I feel, the movement is a quick twist of the kicking hip outward, with a slight lift of the leg. I don't see how you could strain from this kick. As for the power — hell yeah it can take out a knee.

That is more like a scoop kick, you have to be careful with those because on impact you could damage your knee because of the whipping motion. In your video, your knee doesn't extend because you are using a scooping motion.The picture below was taken the same day I made the video. This is a screen capture for a warm up kick. It's the position for a low kick to the shine when the kick is extended. In this my leg is completely straight but in application when you kick something, you want to make impact before that gets straight. My leg looks hyper extended but it's not it's just the pants that make it look that way. In application the leg will only be this straight if you managed to kick all the way through the target. 99% of the time the impact of the kick will prevent it from being straighten out completely. There is a whipping motion in the kick but it's not extreme and it flow with the natural way your knee bends. Here's Video that shows the technique in slow motion. I tried to line it up with the bag so others could have an idea of where my foot will impact.

The best way that I can describe the mechanics of this is to think of it as if you laid a broom against the wall, like the picture below, and then someone told you to break the broom by using this kick. The first thing you'll notice is that you'll naturally change the way that you tried the kick originally. Your kick will have more of a push or stomp type of feel to it, that will allow you to send the force from the kick into the broom. This is something you can try with a broom, and you don't have to break the broom. Just by putting having your leg look like mind and putting pressure on the broom, will give you a good understanding of the direction you need to drive the force of the kick to break the broom.
You want to strike either with the heel or anywhere in the area starting from the middle of the foot to the heel. The closer to the heel you get the more efficient the strike will be.

Eventually you'll learn how to put your hip into the kick. One day I'll do an instructional video for this technique.

 

[Phobius]

You do not aim to break a knee. The goal is to cripple your opponent so he will not continue and that can be done well enough by a regular full power kick to the knee. Trick is to not injure yourself in the process.

Having taken a full powered kick to the knee unprepared and with hard shoes all I can say is, my knee was not broken and I was able to stand on it for a minute or two before I fell down in pure pain. Took me a few years to recover, not sure he ever did recover.

 

[Kickboxer101]

Personally while its not a kick I've eve used or trained that much simply because its not part of my style but I've thrown a few times in the air and yes it would do damage but now this is me genuinely asking what advantages does this kick have over a front leg side kick to the knee I always feel more power off the side kick and Its quicker and harder to see coming because its off the front leg. That's not me criticising it I'm genuinely asking since you'll have a better idea on it than me

 

[drop bear]

Personally while its not a kick I've eve used or trained that much simply because its not part of my style but I've thrown a few times in the air and yes it would do damage but now this is me genuinely asking what advantages does this kick have over a front leg side kick to the knee I always feel more power off the side kick and Its quicker and harder to see coming because its off the front leg. That's not me criticising it I'm genuinely asking since you'll have a better idea on it than me

Different set ups. What if you want to throw a hook after a knee kick?

 

[Kickboxer101]

Different set ups. What if you want to throw a hook after a knee kick?

Yeah sure but I mean the actual kick itself on its own just as a kick not as in how to do combinations with it

 

[drop bear]

Yeah sure but I mean the actual kick itself on its own just as a kick not as in how to do combinations with it

Is that how techniques work? or do they work in combination with other movements.

 

[JowGaWolf]

what advantages does this kick have over a front leg side kick to the knee I always feel more power off the side kick and Its quicker and harder to see coming because its off the front leg.

The movement of this kick is deceptive and it can be use either by itself or as part of a combo. The easiest combo is the 1-2 jab Kick combo (lead jab, reverse jab, and this kick.). The more intense the jab combo is the easier it'll be to get this kick in. The other benefit of this kick is that it travels under your vertical field of vision. When done correctly my opponent's brain will read the movement of the kicking leg as a kick that comes from the side like a low kick that is done in Muay Thai or a front heel kick, but half way in the technique, the brain will assume that I bailed out of the technique as, because that's what it looks like, this misread causes the person to settle in a stance which is usually front leg heavy. Being heavy on the front leg means that the kick is going to land on something that's really solid that won't give much. This is bad for the person getting kick because it's doesn't allow that person to move with / or give with the incoming kick.

The other danger of this kick is that the idea time to use is during the opponents weight distribution. This means things like advancing towards the kicker becomes dangerous. Especially when the kicker gives the illusion that they are retreating. The range of this kick can be as high as the kicker's waist and as low as the ankle. The two targets that one should aim for in self-defense should be the knee, shin, and ankle for the purpose of destroying the.. In a sporting context the kick can be used as a push kick to keep someone from advancing either by targeting the shin or the thigh. I'm against the targeting of anywhere around the knee. The only way to protect the knee from this kick is to use one of those deep martial art stances. The more bend in the need the better so long as you don't go beyond 90 degrees. The kick is destructive so stance training will help strengthen the ligaments and tendons that support the knee. When I experienced this kick, I could feel where the damage would have been had I received a kick at full force. The weaker a person's ligaments and tendons are the more damage the kick will cause even while in a good stance that protects the knee from hyper-extending. The surprising damage was how much damage the inside of my calf muscle (where it's close to the bone) took. For 2 weeks there was discomfort that felt like bruising on the inside of my calf muscles.

At full force I think a trained kick with technique can break the shin, the knee, or the ankle. If shin doesn't break then the calf muscle will suffer and eventually anything that requires the use of the calf muscle will be difficult or impossible to do. I was able to trade 5 kicks but on the 6th kick I fell to the ground because my shin could no longer support me. These were 5 kicks from a person who didn't quite have the technique down. So I can only imagine that it's much worse for someone who trains this kick and understands how to connect the power for it.

When it comes to martial arts techniques, I don't think one is better or more dangerous than the other. Each technique is a tool and you have to pick the right tool, at the right moment, that fits the job.

For me personally this kick fits well with my deceptive fighting style.

 

[Gerry Seymour]

Personally while its not a kick I've eve used or trained that much simply because its not part of my style but I've thrown a few times in the air and yes it would do damage but now this is me genuinely asking what advantages does this kick have over a front leg side kick to the knee I always feel more power off the side kick and Its quicker and harder to see coming because its off the front leg. That's not me criticising it I'm genuinely asking since you'll have a better idea on it than me

Different body positions for each. I was playing with this kick the other day, deciding if I want to add it to my arsenal. It seems it would be easier to make solid contact with the leg than with a front kick. That's because, like a side kick, you have some leeway in which part of the foot strikes. Off an inch with a front kick when striking a narrow target like a kneee (head-on), and you're in a soft area, but with a side kick you can still be in a valid striking area.

 

[JowGaWolf]

Different body positions for each. I was playing with this kick the other day, deciding if I want to add it to my arsenal. It seems it would be easier to make solid contact with the leg than with a front kick. That's because, like a side kick, you have some leeway in which part of the foot strikes. Off an inch with a front kick when striking a narrow target like a kneee (head-on), and you're in a soft area, but with a side kick you can still be in a valid striking area.

let me know if you sample a few kicks to the shin to see what it feels like. If you do, let someone with control do the kicks so that they can start off soft with kicks to the shin and then gradually increase power if you desire. Keep the knee bent and only target the shin with the kick. Don't start at or do 50% power with this kick. I was stupid when I did it at 50%

 

[Gerry Seymour]

let me know if you sample a few kicks to the shin to see what it feels like. If you do, let someone with control do the kicks so that they can start off soft with kicks to the shin and then gradually increase power if you desire. Keep the knee bent and only target the shin with the kick. Don't start at or do 50% power with this kick. I was stupid when I did it at 50%

I do have a student I'd trust with that. He has almost a decade of Shotokan, shows very good control, and actually worries about hurting people. The biggest problem will be convincing him it's not a trick to make him fall down. I don't know where he gets such ideas.

 

[RTKDCMB]

This kick is very useful to attack the knee of an attacker whilst you are on the ground.

 

[Buka]

I've always thought of the kick as more of a "check" to stop the forward movement of an opponent, used in conjunction with following hand strikes, grabs, etc. And, yes, thrown hard it can hurt like hell. I suppose the same could be said for all techniques.

One word of caution - a common habit of any striker is stepping in with the front foot to deliver something with the back foot or hand. Nothing wrong with that step, as long as you are aware you're doing it and it's part of your footwork, and not a habit. I, and many others, have made a living off of people habitually stepping in with that front foot.

And when someone steps in with that front foot - that kick shown is the perfect counter to check that step.

 

[Ironbear24]

What is the striking surface of this kick?

 

[JowGaWolf]

What is the striking surface of this kick?

The striking surface for this kick is anywhere in the area between middle and heel. You don't want to the impact to be directly in middle and you don't want it to be too far back on the heel. When you do this kick your foot will want to have your foot turned outward at about a 45 degree angle when it strikes. You don't want to hit the shin with the foot being vertical because then you risk slipping off the shin, which kills the effectiveness of this kick. You also don't want the foot turned horizontal because not only will the kick be ineffective but it will also cause damage to your knees.

People always debate the value of stance training. This is one of those techniques that validates stance training.

 

[Kung Fu Wang]

The striking surface for this kick is anywhere in the area between middle and heel.

IMO, by using the "reverse side kick" to attack your opponent's leading leg has the following issues:

- You have to kick with your back leg.
- The distance that your foot has to travel is pretty far.
- When you kick with your back foot, your opponent can sweep your leading leg.
- It takes too much time between the 1st kick and the 2nd kick. It's hard to use it as "chain kicks".

I prefer to use the "toes push kick" instead.

- You can kick with your leading leg.
- The distance that your foot has to travel is shorter.
- If you back foot is outside of your opponent's kicking range, when you kick with your leading leg, your opponent's leg still cannot reach to your back leg.
- You can kick out multiple times as "chain kicks".

 

[JowGaWolf]

IMO, by using the "reverse side kick" to attack your opponent's leading leg has the following issues:

- You have to kick with your back leg.
- The distance that your foot has to travel is pretty far.
- When you kick with your back foot, your opponent can sweep your leading leg.
- It takes too much time between the 1st kick and the 2nd kick. It's hard to use it as "chain kicks".

I prefer to use the "toes push kick" instead.

- You can kick with your leading leg.
- The distance that your foot has to travel is shorter.
- If you back foot is outside of your opponent's kicking range, when you kick with your leading leg, your opponent's leg still cannot reach to your back leg.
- You can kick out multiple times as "chain kicks".

Those issues aren't as detrimental as they seem.

 

[Kung Fu Wang]

Those issues aren't as detrimental as they seem.

Assume you and your opponent have the same speed.

Let the distance between

- your leading foot and your opponent's leading foot is X.
- your leading foot and your back foot is D.

1. If your use your back leg to kick your opponent's leading leg. Your back foot has to travel D + X.
2. If your opponent uses leading leg to kick your leading leg, His leading foot has to travel X.

X < D + X

 

[JowGaWolf]

Assume you and your opponent have the same speed.

Let the distance between

- your leading foot and your opponent's leading foot is X.
- your leading foot and your back foot is D.

1. If your use your back leg to kick your opponent's leading leg. Your back foot has to travel D + X.
2. If your opponent uses leading leg to kick your leading leg, His leading foot has to travel X.

X < D + X

It doesn't matter if my opponent has the same speed or is even faster. What matters is my ability to time the kick and to throw it at the correct time. If I can do this then my opponent will not be able to react to it fast enough to get out of the way.

You can't always measure the effectiveness of a technique by the distance a technique travels. If I strike when my opponent is least prepared to deal with the strike then my strike will land. People use the rear leg for low kicks to the lead leg all the time and the ones that are done with correct timing have a high success rate of landing with the opponent not being able to do anything about it. For example, these kicks are rear leg kicks that have to travel a greater distance than the shin kick that I do. If you notice they are thrown when his opponent is least prepared to deal with it.

The shin kick is no different and actually travel a shorter distance than the circular kicks in the video.
I train these kick all the time and even free sparring I can tap my opponent's lead leg without problems. Students at a lower skill level than me are able to land these kicks with ease too. The only difference between them and me is that they are still having problems connecting the power to this kick.

If people kick me with their lead leg then I just counter that kick with the appropriate technique.