What does it mean to "chamber a kick"?

Question

I've read that tons of time on forums and heard it in many videos.

The explanations always seem kind of vague and to this day I can't explain what it is to "chamber a kick". I know it's very important, maybe I'm already doing it (I probably am, I have some years of training behind me).

The main problem might be that I'm French, so the signification of "chambering" isn't clear to me.

So, what does it imply to chamber a kick? There probably is a "canon definition". What are the steps towards this?

I'd like a "canon answer", to try and make this a reference for anyone who'd have this question in the future.

Answer 1

Chambering is an analogy drawn from firearms. In firearms, you chamber a round (put a bullet in the chamber). In the same way as you chamber a round in firearms, you can chamber a kick to "fire" it. This is very probably an American saying in martial arts.

When one refers to chambering a technique (any technique, but in this case a kick), they mean fully drawing back the technique in preparation for exploding forward. In looking for images to illustrate this point, I was disappointed because I cannot find an example of a good chamber for a sidekick. So I'm going to ask you to use your imagination.

In image #4 this is what we mean by chambering a sidekick. This stylist is illustrating a poor chamber. His knee should be tightly tucked into his chest instead of far out from his body, and his heel should be pointing directly out at his target. Thus, when executed, the sidekick should pump quickly and powerfully out, then retract back in like a piston.

EDIT

To further illustrate the point, the following is a sequence of throwing a front kick. There are twelve images. If we number those images top to bottom, left to right, the 9th and 11th images are chambers for a front kick.

Likewise, in the image series below, images #10 and #12 are chambers for a round kick.

A chamber is, very simply, the inverse of the executed technique. To use a punch as an analogy, the fist on the hip is the chamber, whereas the fist that is punching is the technique. Notice that the chambered fist is exactly the opposite of the punch. It is supinated, whereas the punch is pronated. When the chambered fist is thrown it will twist. There is some yin/yang stuff going on here, but it need not be thought of esoterically, but rather as physics.

Chambering adds power to the kick

By chambering the kick fully (especially in the example of the sidekick) you are adding power to your kick in two ways:

1. By fully drawing back, you are increasing the distance your kick will have to travel. The further it has to travel, the more speed it will develop en route to its target, and therefore the harder the impact will be. This is a game of inches, so drawing back even a little more than you could before will help.
2. By fully drawing back, you are targeting the area of your opponent's body that you want to hit. Your kick will follow a straight trajectory to the target. Any deviance from a straight trajectory (i.e. "sweeping your kick") will detract power from your kick. This is true in round kicks and other circular kicks as well, though in those cases the trajectory is circular, not straight, but still should be as direct as possible and deviate as little as possible from its trajectory.

Answer 2

Chambering a kick means mainly actively pulling your heel to your glutes, ready to 'shoot' as explained in the other answer:

By doing that, you prepare your body to produce as much power as possible. Where your knee should be (the picture being a bad example) depends on whether you extend (straight/hook/push kicks) or flex your hips (roundhouse) during the execution of the kick. Why that is the case will hopefully be clear after the following remarks.

Two biomechanical principles of chambering

Besides the points mentioned in the other answer (longer way of acceleration, (more) straight trajectory), there are also other, biomechanical reasons why chambering makes sense in terms of power:

1. You pre-stretch the muscles that are about to work for your kick.

That means that since you extend (straighten) your knee in the kick, flexing it maximally always makes sense. That way, you pre-stretch your main knee-extensor, which is the quadriceps. As soon as you loosen the chambering, the elastic muscle will automatically go to neutral length without you having to do anything, ie. you get some acceleration "for free", as it were, since the muscle does not have to exert any energy for that and any contraction will only add speed.

But what about your knee position? If you do a roundhouse, you engage your hip flexors, ie. the muscles that pull the knee towards the chest. Accordingly, a good chamber for a roundhouse will involve some hip extension, ie. pulling your knee back to achieve this pre-stretch. Conversely, a push/hook kick will ideally be chambered with your knee close to your chest.

2. Due to antagonistic inhibition, you will have more rested, available muscle fibres that can add power to your kick.

All the time, the muscles work to hold your weight and the position of the joint. Since individual muscle fibres have a refraction time, ie. need to rest for a bit after each contraction, there is a constant interplay of muscle fibres waiting, resting, and contracting.

Now, when you properly chamber a kick, you actively engage the antagonist of the muscle you need for the kick. That not only means that this muscle you will need has less work to do for that moment, due to neural reasons it also means that there is a neural inhibition of that muscle, ie. all (or at least most) of the fibres have time to rest since no (to be exact: less) neural signal comes through that tells them to contract. This mechanism is in place so that the muscles do not constantly work against each other in movements.

The outcome is that the moment you loosen the chamber, not only the pre-stretched muscle will add power due to elastic retraction, there will also be a higher percentage of rested muscle fibres not in refraction time so that you can engage more muscle fibres at once for your kick. The kick can be more powerful.

A remark on the problems and limits of chambering

Of course, the very same principles apply to punches. And it certainly adds power and end-speed. While this is all well and good, chambering perfectly is rather for forms than sparring since obviously, having a longer way of acceleration and an additional move before you execute your technique also means your opponent has more reaction time available. They will simply be able to see what is coming in what direction with which limb.

Answer 3

In addition to the existing excellent answers, in my experience, chambering the kick is also heavily emphasized in early training in a number of martial arts because the act of chambering makes the kicks more standard and neat, helping to eliminate sloppy technique or just throwing a kick out. It's perfectly natural (and sometimes best) to just pick the foot off of the floor and immediately extend it out into a kick, but as noted by others, this removes a bit of the potential power, and may result in a less stable technique compared to properly chambering (my instructor used to refer to it as "cocking" the kick, furthering the gun analogy) the kick, delivering it, re-chambering, and then setting the foot down.

It's a bit of a chicken and an egg in that, as noted in the the other answers, there are strong benefits to a properly chambered kicks, but in my experience, the primary way in which many students encounter the question of chambered kicks is in getting docked points when doing forms for testing for not having properly chambered the technique.

One additional physical benefit to chambering the kick that I haven't seen mentioned yet is that it can also aid in avoiding the kick getting stuffed before it can start. The chamber happens close to your body, which means it's less likely to hit some part of the environment (or a stray limb of the opponent), or be blocked by the opponent before it can build up power.