Dtyjlui

I have heard a number of judoka promote gripping with only the lower three fingers (pinky, ring, middle) as opposed to all five. I've sometimes heard this referred to as the 'Japanese grip'.

Is there any evidence to support this grip being more effective in judo than grips where all fingers are engaged? Or is this just a stylistic choice?

^{When I first heard this recommended it reminded me of a passage in Musashi Miyamoto's Book of Five Rings:}

Holding the Long Sword

^{Grip the long sword with a rather floating feeling in your thumb and forefinger, with the middle finger neither tight nor slack, and with the last two fingers tight. It is bad to have play in your hands.}

^{When you take up a sword, you must feel intent on cutting the enemy. As you cut an enemy you must not change your grip, and your hands must not "cower". When you dash the enemy's sword aside, or ward it off, or force it down, you must slightly change the feeling in your thumb and forefinger. Above all, you must be intent on cutting the enemy in the way you grip the sword.}

^{The grip for combat and for sword-testing is the same. There is no such thing as a "man-cutting grip".}

^{Generally, I dislike fixedness in both long swords and hands. Fixedness means a dead hand. Pliability is a living hand. You must bear this in mind.}

^{And while in principle it seems sound - reducing fixedness and use of strength in your hand seems to imply having greater [wrist] flexibility and less fatigue - I'd like to see some evidence that it is more effective and is as applicable in gripping a gi as it is believed to be in holding a sword.}

The consensus of opinion on this, based on a brief survey of forums discussing it, is that the 3 finger grip is done for 2 reasons primarily:

1. It reduces fatigue in the forearm muscles. If you're gripping using the middle, ring, and pinky fingers only, then you're not engaging your forearm muscles as much. Instead, you'll be using your wrist muscles primarily. That should reduce muscular fatigue.




2. Reducing forearm muscle involvement increases range of motion in the wrist, making it easier and quicker to adapt to changes in grip. By not engaging your forearm muscles as much, you'll find that you can flick your wrist upwards more quickly. Otherwise you'll be struggling against your own forearm muscles to release your grip, what's known as "antagonistic muscle reflex".

Many grapplers (BJJ, Judo, etc.) readily switch between 3 and 4 finger grips. They might use a 3 finger grip on the lower sleeve, but switch to a 4 finger grip when they move to the lapel. Using a 4 finger grip on the sleeve makes it harder for them to adapt and change to a more secure grip.

While the 3 finger grip is more flexible, the 4 finger grip is more solid. The 4 finger grip can provide a connection with the rest of your body that the 3 finger grip can not. That's useful for getting the weight of your whole body behind your throw or take-down. It can also keep your opponent more immobilized, and therefore keeps you more stable.

Some think that the 3 finger grip makes you less susceptible to finger sprains and breaks. This sort of makes sense, because you can't sprain a finger that isn't involved in the grip. But it may have more to do with the fact that a 3 finger grip simply makes your grip more flexible, so you don't channel all of the torque in the finger tips.

One caveat to the 3 finger grip is that leaving the index finger out and loose is inviting someone to grab it and twist, at least in a real life street fighting situation. And unlike pressure point strikes, this is actually very easy to pull off against even experienced grapplers. Most mainstream BJJ and MMA competitions forbid small joint manipulation for that reason, which means that it doesn't get sufficient attention in training and can leave a hole in your defense. It's debatable how frequent this would happen in MMA / no-holds-barred competition if it was allowed, but there are examples of this in venues where the rules were less restrictive.

Hope that helps.

There are two primary muscle groups at work. The ones which control the 2 larger fingers, the 1st and 2nd phalanges (thumb and index) are controlled with the larger thenar muscles, called the flexor pollicis brevis, abductor pollicis brevis, and opponens pollicis muscles - collectively, I'll call them the thenar muscles.

The 3rd, 4th, and 5th phalanges (middle, ring, pinky) are controlled by a different muscle group which includes the abductor digiti quinti, flexor digiti quinti brevis, and the lumbricals of their respective fingers (I'll call this group the hypothenar muscles). Note that the middle finger only is controlled by a lumbrical and not of any of the hypothenar or thenar muscles. Therefore, it doesn't matter whether or not you use the middle finger with the sword. The same is technically true for the ring finger, but many people have difficulty independently controlling the ring from the pinky, and so the two tend to move together. You could, theoretically, control a sword with only a pinky grip, but I suspect only a good pianist or guitarist could do this, as they have trained to be able to independently control their ring from the pinky sufficiently. Nevertheless, you do want some control over the thing you're holding. Read on:

Now, when you are gripping a sword, you want your hand to be as flexible as possible. That cannot happen when the thenar muscles are tensed and in contraction. You want as much free wrist flexion as you can get, while still holding onto (and controlling) the sword. When the thenar muscles are tensed, they are said to be "in contraction" (that's how all muscles do work: they contract). And in contraction, you may note your wrist loses some flexion. You don't want that when you need your wrist to flex with an object where precision control is needed.

The reason for this is that when both muscle groups are activated, both are contracting, and are controlling the object being held. In order for you to precisely control the sword, you need to dexterously contract and relax the thenar muscles, and time it properly with the desired action you want. This is extremely difficult to do, and what's more, this contributes to fatigue. Ever use a sword for a long period of time and your hand gets tired? Try not to squeeze with the thenar muscles next time, and see if you are thus fatigued in the same way.

When you want rigidity and absolute control, then you need to engage the thenar muscles. This tenses and strengthens the whole hand, and flexion is more limited.

So, fencers, swordsmen, golfers, baseball players, writers (pen/pencil) all need more flexion in the wrist, and are taught many methods to not tense the thenar muscles. In fact, some people have difficulty independently controlling these muscles. Children, for example, often have difficulty, and it is evidenced in their handwriting. Once they learn how to independently control these muscle groups, their handwriting and stamina improves.

And when strong grip is needed, such as when grappling, lifting weights, shooting a gun, using some tools, skiing, hiking (with a pole), or using a knife (eg, for kitchen, butchery, or self-defense), then you tend to want the whole hand as rigid as you can get. Stability is important here.

Here is some more information on the Thenar eminence, which describes how the thenar muscles work and are enervated. It might suprise you to know that not everyone has the same nerve control over these muscles.

You may also find information in the Hypothenar eminence, which describes the other side of the hand.