Thursday, November 6, 2008

Karate punches vs. boxing punches


In my article “Kime: the soul of the karate punch” I described the essential feature of the karate punch as being “focus” – ie. a combination of minimal deceleration before impact and optimum distancing – usually performed in karate with a straight thrust.

Many have, and will continue to, argue that this straight thrust is less powerful than a boxer’s follow-through punches. This is true. But to understand why this does not necessarily mean that the former is less effective we’ll have to examine punching methods – what someone I know calls “delivery systems” – in greater detail. To the extent that karate punching is “less powerful”, I will then go on to examine why this is a tactical choice rather than a necessary failing.

Categorising punches

In a very general sense karate punches can be divided into 2 kinds: straight line and curved. In boxing, punches can be divided into 2 different categories that overlap with the karate ones, namely:
    1. jabs (ie. punches which retract); and

    2. follow-through punches (which don’t – I’ll broadly use the latter to include hooks and uppercuts).
Is it possible to analyse karate punches in the context of the boxing paradigm? I’m going to try.


Jabs are principally straight line techniques; their only real distinction from a basic karate punch is the point of origin (in karate this is at the hip, while in boxing this is from a guard position). However as any senior karateka will tell you, the karate hip chamber is just a basic or “ideal” posture that allows a punch to be “fully loaded” for practise. It is not how the technique will necessarily look in combat. Karate basics serve quite a different function for their practitioners than the boxing equivalents. They are basics as well as isolation drills.

In fact, karate punches can (and should) be performed from any position (for more on this topic see my article “Chambering punches”). They are not limited to the basic “drill” posture that we all see in line practise or kata etc.

For example, when karate punches are performed from a guard they are called “kizami zuki” – a term often meaning “leading punch” but often translated as “jab”. What people seem to regard as the main distinction between the boxing jab and the kizami zuki is that the former is usually performed with a retraction or snap-back, where the latter is not.

As I discuss in the article “Retracting punches vs. leaving the hand in”, this distinction is in fact a red herring: For a start, the retraction of your arm is largely irrelevant to the nature and effect of a punch. A snap-back in no way boosts outward speed.

In any event, non-retracting thrusts are principally used in karate as a training tool for developing and perfecting focus. In higher kata there are many snap punches. Consider for example the video below of me doing snap punches in seisan kata in 1993.

Me doing snap punches in seisan in 1993

Accordingly there is no reason for karateka not to practise and use snapping punches (ie. jabs) other than a rigid adherence to basic form. Far more importantly, combination techniques render the whole "snap back" issue irrelevant: just as in boxing, karate uses a kizami zuki as a "set up" to other techniques, meaning that as soon as it is "thrown" the punch is being retratcted so as to give momentum to a technique with the other arm (eg. a reverse punch or "gyaku zuki"). In this respect karate and boxing "jabs" are really indistinguishable, even though karate basics are often isolated for (kime) practice.

Now while jabs have been known to produce the occasional knockout they are not generally regarded as “power” blows. The reason is simple; they don’t have much space within which to accelerate, resulting in a lower velocity at the point of impact. Using the simple equation p = m x v this means the amount of momentum generated will be less, hence the amount of momentum transferred (the impulse) is going to be smaller and so is the amount of force applied to the target. (For more on the physics, see my article: “Hitting harder: physics made easy”.)

Given that the principal karate punch is a straight thrust and that it corresponds with the boxer’s jab, it is little wonder then that karate punches are seen as “less powerful” than the rest of the boxer’s arsenal – the “follow-through punches”.

Follow-through punches

With the exception of jabs, boxers don’t attempt to stop their punches at a predetermined point. Instead they adopt a “follow-through” to their punches. This is less evident with uppercuts (“ura zuki” and “tate zuki”) than, say, hooks or crosses. However the karate variants all involve a distinct “stop” executed by the performer. The boxing versions either swing past or, in the case of the uppercut, continue until they have exhausted their velocity at the end of their vertical flight path.

The powerhouse of follow-through punches is, of course the right cross (or just “cross”). Those who have read my article “Chambering punches” will be aware that there is an equivalent in karate which I have called the “kosa zuki”. In both cases it involves a punch loaded just above waist level with the elbow away from the body. Then the fist is raised and the punch is executed so that it passes through the hypotenuse of the triangle formed by you, your opponent and your (right) hand. In other words it “crosses” your (and your opponent’s) centreline.

This hypotenuse provides a longer path, hence more time to accelerate, hence a better chance of reaching a higher maximum velocity. If the full range of movement is used, and the body parts act in a staged way to transfer momentum in a whip-like sequence from larger to smaller body parts, then the fist will be accelerated to the fastest possible speed. A reverse punch is biomechanically better suited to transfer momentum in this way than a leading arm punch. And the cross / kosa zuki is, of course, a reverse punch.

An analysis of the kosa zuki or cross punch

As you can tell from the description and the picture above, the punch ideally follows a straight line in order to prevent interception or evasion; after all, the shortest distance between 2 points is a straight line. It is for this reason that even in boxing the cross is sometimes called a “straight cross”.

However in most boxing contests the cross invariably follows a curve to some extent as you will note from the video below. This is partly because, unlike karateka, boxers don’t attempt to stop their own punches at a predetermined point except, as noted above, when they are jabbing. In the absence of a deliberate “stop” by the performer, a punch executed on a horizontal plane will always tend towards a curving follow-through given the biomechanical structure of the human body (ie. in particular the positioning of the elbow to the side when an arm is naturally extended outwards).

A boxing knockout showing a distinct “curve” to the path of the punch

When a cross / kosa zuki follows a curve it obviously travels an even longer distance than a “pure” straight cross. The further the punch travels from the chambered position to the target, the more time it has to accelerate and the faster its maximum velocity will be (at 80% extension – see my article “Kime: the soul of the karate punch”). This is why the cross carries more momentum than any other punch.

How gloves affect dynamics

Now it is important to note that fighting with gloves creates its own unique requirements: The padding of the gloves spreads the pressure over a wider area, diffusing the force. By contrast, a bare knuckle punch exerts pressure to a smaller area and causes more localised damage with the same force. This can be understood by comparing a flick with a towel to a strike with a pillow: assuming the same mass and velocity at impact, the towel flick will cause more damage.

Accordingly a boxer in a ring must prioritise force at all costs: where a simple jab might be determinative in an ungloved situation (eg. a finger in the eye), a gloved jab of the same force might be no more than a minor inconvenience. In other words, in order to be effective, a gloved punch must transfer more force than its bare knuckle equivalent.

Maximum force: the need to increase both speed and contact time

As I discuss in my article "Hitting harder: physics made easy" maximising transferred force can be undertood by reference to the following equation:

Force = impulse (transferred momentum) / time.

Using this equation, you can see that a boxer first needs to maximise the velocity of the punch. As I have just noted, the boxer can do this by adopting throwing a cross punch from a higher chamber (to line the arm up with the hypoteneus of the triangle) and very likely with some element of curve (because of the natural follow-through).

Second, the boxer needs to maximise the time during which the punch is in contact with the opponent (in order to transfer as much of that momentum as possible). Happily for the boxer, this is another direct consequence of using a follow-through punch: in much the same way as a golf drive uses a follow-through to drive the ball as far as possible, the follow-through punch ensures both maximum velocity and maximum contact time with the target.

Follow-through vs. "kime"

The need to maximise force at all costs in a gloved contest has a profound effect on tactics and training methods for boxers vs. karateka. For example, a large part of a boxer’s training is necessarily devoted to “power” training; heavy bags are hit with deep penetration or with blows that are seen to displace1.

By contrast, a large part of a karateka’s training is, just like a sword practitioner’s, necessarily devoted to honing maximally efficient “kime” or focus via an endless repetition of “cut-like” blows that should minimise displacement while causing sharp, localised damage with straight bare knuckle thrusts.2

“Kime” or focus is designed to make such thrusts more efficient. On the other hand, such punches are of limited effect in a gloved context.2 Moreover, focused thrusts are inherently conservative (for example, see my article "Stopping techniques at a pre-determined point"), making them less useful in a contest where your goal is to defeat your opponent (as opposed to a civilian defence goal of "not being defeated"). Last, it takes a long time to develop good “kime” or focus to a point where it is likely to be applicable under stress.

For these reasons, karate is not readily adopted as a “delivery system” for sports combat. It is profoundly unsuited to glove dynamics2 and developing it is, in any event, a long-term proposition.

So why bother with karate punches?

All of this poses the inevitable question, why don’t karateka simply adopt boxer’s tactics? As I have foreshadowed, this is largely answered by examining goals/motivations.

As I stated in my article “Civilian defence systems”, arts like karate aren’t designed to "beat" an opponent or score a point. Your principal goal isn't to "land a knockout blow". Rather, you are trying to defend yourself. Yes, this might involve a "knockout blow" - but it might not. In the course of this defence, your counters will tend to be conservative precisely because you aren't focused on "winning" – you are focused on not being hurt. Yes, the former and latter might end up being the same thing, but to suggest that they always will is a gross oversimplification of civilian defence needs and responsibilities under the law.

Since any attack/counterattack leaves an opening, civilian defence counters have to be conservative – they aim to minimise that opening. As I noted above, in order to make boxing blows more forceful you have to have some follow-through, meaning some element of curve. This increases momentum, and contact time, significantly. But it also increases the overall “flight time” of your blow, hence making it easier to intercept or evade. It also leaves a larger opening.

Hitting someone with a less than optimally powerful blow in boxing is problematic; you’ve wasted an opportunity to land a knockout and your gloved fists will ensure that its effect is reduced even more.

On the flip side, hitting someone with a less than optimally powerful blow in self-defence might be all that is needed. A poke in the eye does not require a great deal of force. Nor does a stop to the shoulder. In the end you might daze your attacker or do something else that is sufficient to enable escape or thwart further attacks. The latter is something that Marc “Animal” MacYoung calls “cutting the supply lines” (see his article "Generating Power"). As he puts it, you don’t necessarily have to “crush your enemy” in order to defend yourself. It can be sufficient if his “army” is unable to fight.

In other words, your goals have a fundamental impact on your tactics – and hence on your chosen “delivery system”.

Which is "better"?

In my view if you were to compare the results between identical twins, one training in boxing punches and one training in karate punches, then after one or 2 years the boxer would probably generate both more visible force and more applied force. However this is not to say that the karateka would be willing to swap “delivery systems”.

Certainly if I were scheduled to climb into a boxing ring in a month’s time, I’d be hurriedly brushing up on my boxing punching – not attempting to apply the karate “delivery system”.

But on the other hand, I believe karate is much better suited to my own goals of civilian defence.


Many people are inclined to dispute my assertion that combat sports are different from civilian defence arts. They maintain that “fighting is just fighting”. While it is true that boxers are phenomenally good fighters all round (ditto MMA, Muay Thai, etc.) their disciplines are intended first and foremost for competition in a ring. This doesn’t mean that they are inapplicable in a street confrontation. Far from it. However by the same token, just because civilian defence systems like karate are not suitable for use in a combat sports ring does not mean they are not fit for their purpose.

I’ve written this article largely to address the misunderstanding in the broader community as to why arts like karate have such different “delivery systems” from systems like boxing. Because Eastern civilian defence systems are much harder to understand intuitively (given that they take many more years to perfect) they have become an easy target for dismissive assertions that they “don’t work”. In my personal experience, they work very well for the purpose for which they were designed.


1. The more follow-through / contact time, the more you will “shift” or “displace” your opponent and the more forceful your punch will be - and be seen to be (see my article “Visible force vs. applied force”)! Having said all this, the displacement from a very forceful gloved punch (as opposed to a mere push) is still going to be relatively small; you’ll notice that while the knockout blow in the above video did move the opponent a little, it was still not so great as to knock him across the ring.

2. It is important to note that the padding of a glove makes it very difficult indeed to focus any punch in the karate sense of that word. Clearly all effective punches are focussed; if a boxer’s punches weren’t focussed they would be aimless and ineffective. All effective blows are, to some extent, focussed on a target. And just as with the differences in displacement generated by the different “delivery systems” can be slight, the differences in levels of focus are actually quite slight too. However it is those last few increments that are the hardest to achieve. The karate concept of “kime” is modelled on a bare-knuckle delivery system that focuses destructive force on a small area. The very purpose of a boxing glove is to distribute force over a wider area. And this runs directly counter to the concept of "kime".

Copyright © 2008 Dejan Djurdjevic