日本語版 https://www.jsgym.net/blog/jeet-kune-do-sidekick-vs-boxer-jab
I came upon this quote on the internet a while ago:
“I’m using my longest weapon, my side kick against the nearest target, your kneecap. This can be compared to your left jab in boxing, except it’s much more damaging.” – Bruce Lee
First of all, I am fan of Bruce Lee of course but when you're a fan you sometimes forget that the person you're a fan of is a person, just like yourself. And people are not perfect. Since Bruce Lee died way too young, but nevertheless managed to say and write a lot during his brief time on earth, he cannot control how he's statements are being used (which are often taken out of context for business purposes). And he cannot make corrections to his previous statements.
One of the things I've learned during my time as a wing chun teacher is that your understanding of martial arts changes and deepens. What you thought you understood, you really didn't understand at that point in time. At least not to the extend you might do many years later.
Now let's get back to the JKD side kick and try to compare it with the boxer's jab and look at the pros and cons. Since Bruce compares it with a jab I'll consider it used in the beginning and during fight, and not as a fight ending last attack (the only way I would use it as a wing chun practitioner!):
The side kick might be more damaging if, and only if, it connects with the kneecap at the right angle, at the right distance, with the right timing. The problem with kicks in general is that they are slower than punches so if we were to put a side kicking Jeet Kune Do practitioner up against a jabbing boxer, my money is actually on the boxer using a jab rather than the JKD side kicker if asked who hits first, or benefits the most from the attack.
First, the Jeet Kune Do side kick:
In order to kick you need to transfer your weight first.
If your kick is too high or low you don't get the effect that you were wishing for and you might have opened yourself up to a counterattack.
The same goes for the distance: too close and the kick is weak, too far away and you miss the target completely.
Timing: What if the opponent is moving? The kneecap is a rather small target and it's probably easy to time the kick wrongly and miss the target when there's movement involved.
Now let's look at the boxer's jab:
There's very little preparation needed for a jab. No need for transferring much weight.
The target is the opponent's head, which is bigger and easier to hit than a kneecap. A counterattack is almost always a possibility but you're in a better position to follow up than after a side kick.
Distance doesn't matter as much as the purpose of the jab is to measure distance and set your opponent up for the next punch. Timing is easier because it's easier to change direction on a punch than a kick. But the target is more moveable than the kneecap which can make it difficult to hit the target with a lot of power.
Let's recap:
When it comes to damage, the side kick wins. No doubt about that.
When it comes to risk assessment, the side kick will often be much more risky than the jab because of the small target, time needed for transferring of weight, difficult timing, etc.
So for the average person the jab is probably the better and safer technique.
For Bruce Lee, maybe his kicking ability was one of a kind but the chance of you being as fast as Bruce Lee is minimal.
I would practice the jab if I had to choose between the two techniques (though there's no use for a jab if you're using wing chun).
Bruce Lee on the other hand, might never have changed his fondness for the side kick.
