Oi Zuki is well known in karate because it is often worked in kihon.
It is a technique of fist (Tsuki) coupled to the displacement Ayumi Ashi in position Zenkutsu Dashi. This is called the pursuit punch. That is to say, one step forward while putting a punch. The fist technique must simultaneously arrive at the stabilization of the position.
Said like that, the technique seems very simple, but Oi Zuki requires a lot of training to be perfectly mastered (although we probably never achieve perfection with Oi Zuki ;))
We are going to fully understand the difficulties of this Tsuki, break down Oi Zuki by analyzing the various muscle groups in action. In a future article, I'll give you other ways to work on Oi Zuki by changing the use of your spine
Decomposition of Oi Zuki:
We will position ourselves in Zenkutsu Dashi the body of 3 / 4 face (Hanmi).
As for a Gyaku Zuki, we will trigger, through the Hara, a vibration at the hips. This vibration spreads such a wave in the hind leg with contraction of the glutes, quadriceps and calves, thus generating a strong thrust in the back heel.
Everyone knows the principle of action / reaction (Revisit your Physics classes;)), so this push back causes a forward force of the body.
As soon as the center of gravity of the body passes in front of the front foot (which will be called "back feet"), we will continue our journey with an 2th vibration which this time is going to spread at a time in the other leg (glutes-> quadriceps-> calf) and in the front arm (contraction deltoid-> triceps-> forearm) to hit Zuki with the front fist.
During all the movement, the hip that was behind initially will move forward and thus rotate the body. This pivot spreads to the shoulders triggering the Tsuki.
The final kime must be synchronized with the stabilization of the displacement so that the return energy of the impact can be cashed up to the rear feet.
You must feel these two vibrations that start from the belly as two successive explosions of the energy of the Hara. Everything is done in continuity, without downtime. The first vibration triggers the movement, the other accelerates it.
And most importantly, you have to synchronize the second vibration with your displacement:
Indeed, if you make your Zuki too early, you will have almost no force in the fist at impact since your kime will already be past.
Conversely, if you do your Zuki too late, you will lose the energy of movement and will not have more power than on Mate-Zuki (punch on the front arm.)
You have to push once in each leg. The first time generates the displacement, the second time accelerates this movement and gives the technique.
If you are well synchronized and especially if you do not no muscle tension which slows you down, you should have the power of 2 legs, body rotation and arm extension that come into the fist at the same time.
As Gyaku Zuki, In Oi zuki the body remains straight, the back is contracted, but not arched. One draws well the reverse arm back (Ikité).
A strong pressure is maintained on the ground by a contraction of the adductors (One puts the force between the thighs) and one locks well the shoulders by contracting the muscles under the armpits.
To help you improve on Oi Zuki and to work on simultaneous outbreaks of 2 legs, I have concocted a training video.
I'll let you put on your kimono and find you immediately on the video.
(Do not forget to warm up before, thanks to the advice I give you in the ABCs of warming up , my book to download for free ;-))
That's it, I hope the training was good
Coming soon, I will tell you about 3 Ways to Use the Spine in Oizuki to add power to your fist.
But in the meantime, I'm waiting for your questions and remarks in the comments below, I'll be happy to answer you.
Thank you and see you soon,
"How to succeed your grade passes"