A few months ago in the dojo our instructor grabbed out the rebreakable boards and we worked on a palm heel through it. Then he put two boards together.
Then for a bit of fun he asked if anyone wanted to try and break the two boards like this: extend your arm, fingers outstretched and tips touching the board. From THAT distance palm heel. Put up my hand and said "oh yeah sure I'll give it go!"
No idea if I could or not, but I knew the mechanics and proper relaxation and alignment that was theoretically needed. First attempt it didn't break, so I shook it out, relaxed about tenfold more than before, and really honed in on my breathing and connection with the ground, and utilising my feet.
BOOM! I honestly surprised myself and instructor was rather impressed haha. Very cool! Chinkuchi is the term I believe is used for this sort of thing, or a really good understanding or expression of that principle.
I am curious, is rebreakable boards easier or harder to break than real board? I have rebreakable boards, never try the real boards as I am too cheap. I found rebreakable boards are not that easy to break. One is very easy, but stacking 3 with no space is not so easy. I actually broke my knuckle when I broke 3 boards with no space between in the holder that tied onto a heavy bag(so I could punch horizontally instead of punching down. I worn a thin Everlast bag glove that is about 1/4" thick padding, still broke my knuckle. Just curious how does this compare with real boards. Since I broke my knuckle, I never dare to do it again. Just want to find out how many real boards I can break WITHOUT actually try it again.
Ha ha, finally I see the word "CHINKUCHI" here. I mentioned this a few times and nobody responded to that!! The idea is very simple, nothing mysterious about it at all. Doing it is hard, a lot of practicing. Like I said, you can feel it and hear it if you do it right on a heavy bag. It feels and sounds different.
It's about about Chinkuchi, be it 1", 6" or longer punch. Longer punch can hit a lot harder. This is just physics, it's like car testing in 1/4 mile run. They set the fix distance for the car to accelerate from dead stop to max speed. If the distance is longer, the faster the car will be at the end because it has time to gain speed travel the longer distance.
So for 1" punch, you only have 1" distance to accelerate, it is slower than if you have 3", 3" is slower than 6". This is simple physics. There is NO WAY the same person can punch just as hard at 1" vs 6" if everything is done the same. It's that simple. This means if one practice hard enough, his 6" punch is going to much harder than 1".
That's the reason I said it's useful to practice, but don't get too hung up on it, more practice, better one can achieve Chinkuchi.
BTW, all the 1" punch I saw including Bruce Lee has a
lot of PUSHING element in it rather than penetration. A good penetrating punch does NOT move the object backwards. This is very basic also, a good punch penetrates the heavy bag, not pushing the heavy bag. One can easily see how good a person punch by looking at the heavy bag and how it sounds. A good heavy punch doesn't move the bag a lot, the punch make a bigger dent into the bag. That if one punch a few punches, the bag just slowly move back, not bouncing all over the place if he achieve Chinkuchi. Also it sound very different, very echoie sounding, have a deeper sound. Idea is simple, doing it right takes a lot of practice. I just never take 1" punch serious.
