One of the defining characteristics of particular styles of kung fu are the hand shapes. In the USA, many kids who grew up on Sunday afternoon/night “Kung Fu Theater” shows in the ’80’s have done some version of the Shaolin Five Animals by striking poses while stating the names. And even kids complete unaware of the intricacies of Chinese culture knew instinctively that the styles we were aping were defined by their hand shape. Tiger: the classic claw, Crane: with the fingers touching at the tip making a beak shape, Leopard: with the hand clenched in a knuckle forward paw-like half fist, Eagle: a claw shaped hand with the finger touching at the sides, Snake: A flat hand with thumb against the side of the hand.
While these playful antics were fun, these hand shapes do serve an important purpose. I should say, many important purposes. Hand shapes not only add flavor and flair to a set, they help train grip, hand work, and whole body connectivity. Yes, they do serve performative function and a nemonic one. The Crane fist looks like a beak, the snake fist looks like the head and tail of the snake, etc. But the movement of the entire hand, wrist, and arm are altered by holding the hand in a specific shape, or by forming the shape with movement.
Talk to the Hand

All styles of Kung Fu have their own collection of hand shapes integrated into their training. These come in a variety of names dependent on the style, but can be boiled down to a few categories of shapes. Most hand shapes will fall in to one of the following types: fists, palms, claws, and hooks. There are also hybrid hand shapes formed by combining qualities of each type. Each these types have applications and physical qualities that are fairly similar across all martial art. While I am focusing on the Chinese systems, since that is where I come from, the other asian styles also use hand shapes to great extent.

The hand is a very complicated limb. It contains many separate organs and muscles groups. The articulation that is possible with our hand is immense and, as a result, the ways in which our hand functions are also almost limitless. As we talked about before, human movement and the science of kinesiology, are based on some fundamental principles.
In their home styles these hand shapes are given specific jobs and applications. But sometimes, a hand shape can be held for long periods of time. Sometimes through an entire set. While this may seem arbitrary and stylistic. But there are actually forces of biomechanics that are being exploited here, even if it is unconsciously. These processes help create tension and effort while the hand is in different positions. In this way hand shapes are a good way to improve over all grip strength and functionality.
Strength and Flexibility
This topic deserves it’s own discussion but a quick touch on it here is in order. Strength and flexibility are not, as many assume, inversely related. The stronger you are, the MORE flexible you should be able to be. Flexibility and range of motion are huge factors in safe training and injury prevention. But often people assume that increases in strength will decrease flexibility. This is patently not true.

What people are thinking about with this common mistake (one which has been a part of athletic training for too long) are the two functions of the muscle; extensibility and contractibility. We discussed this briefly with the types of contractions, and those do come to play here, but more important to our discussion is something called the ‘length/tension relationship”.
All of the muscles in the body can extend and contract. This changing of length is the major power producing action created by your muscles. But each muscle has a specific set of parameters about where and how it can activate depending on how long it is at the time. There is a sweet spot for each muscle and muscle group between these two extremes. The maximal contraction in any given muscle is dictated by length. If. a muscle gets too long, it tends to loose the ability to contract and remain at that length. When it is short, it cannot contract more and must release before it can extend or elongate.
All of this has a global effect on your body. Most of these processes are autonomic in nature, meaning you do not have direct control over them. In trying to train ones self as a high performing individual, we must train these things so they are a benefit to us not a hinderance. We must teach our body and muscles to activate at man lengths and produce many levels of power from each. Knowing ones limitation in this area is a huge advantage in training.
Hand shapes, as they are used in kung fu training, help train the hand to contract and extend and hold isometric contractions at various lengths and positions. These will have a net effect on the grip as a whole, allowing the hand to squeeze and produce force through more of the movement for a greater effect.
Another process that is very useful to martial artist in training hand shapes is, irradiation. Muscle irradiation is the technical way of saying that a great contraction in one muscle will stimulate a greater activation in the other muscle involved with the action. The simple example of this that you can do yourself is make a fist and squeeze it as hard as you can. You will feel the tension created move in to your arm. You may even feel it in the shoulder and neck. This neuromuscular phenomenon is one of the systems in our body that helps us create coordinated movement while staying stable and producing force.

The different hand shapes have different metrics for both of these. By moving around and performing actions using the hand shapes, they are patterning your hand not only to work with it self better, but also it is connecting it to the rest of your body.
The Types
Fists:

Fists are hand shapes where the fingers are closed. The tension and effort created is in toward the palm in a squeeze. The most basic types of fist are “Sun” and “Dragon” Fists. The Sun Fist is a vertical fist with the space in the hand by the thumb is upward. It is called this because it resembles the character for “Sun” 日. The Dragon Fist is the horizontal fist, with the thumb and pinky side of the fist facing to the sides. Other style of fists will clench different fingers more than others. Some my align the fingers and surface the fist differently as well. But the basic idea of wrapping and clenching your fist together remains the same.
Making a fist is an intuitive act. We often make fists when we are emotionally disturbed, frightened, or angry. It is very much linked to our fight or flight response. The clenching of the fist happens because of several things combining together. The hand and shoulder are neuro-muscularly linked in many ways. One way is by the rotator cuff. The RC Contracts and activates when the hand makes a fist. The shoulder is a very mobile joint, making it very unstable. The grip of the hand stimulates the rotator cuff to hold the arm in place as it is about to receive force or resistance. Without this function, your shoulder would dislocate all the time.
The different variants of fist found in martial arts styles is usually aimed at altering the surface area or creating a more focused impact. This is ostensibly to create a small point of impact, often aimed at particular areas or targets. This does not necessarily mean that impact is needed in the use of such a fist. More often than not, one uses this fist in sparing to push tender areas or push in body cavities during wrestling situations. Other fists like crane, monkey, or ginger fists, aim to brace the forearm musculatures. This technique will use wrist position as well to increase the irradiation that can come from the fist. The different shape of the fist allows different muscle groups to activate and stabilize while others can relax and allow different kinds of movement.
Palms:

Palms utilize the open hand. They tend to favor striking with the surface of the palm and the ulnar side of the hand. There are several different palm shapes used through various martial arts in China. The main differences between them is the position of the thumb, the spacing between fingers, and striking surface primarily used.
There are two basic categories of palm as well. Since there is more freedom in the hands movement with the finger extended this creates the need to come up with ways to protect the fingers and thumb from being bent back or otherwise compromised. The first way to do this is what I will call “Knife Hand”. This is a palm position that has the fingers press together, the thumb against the side of the hand and fingers straight. This hand shape tends to be used for more striking purposed because of the tucked nature of the fingers and thumb. Chops, slaps, finger jabs are common practice with this type of palm.
The next basic type of palm is the “lotus”palm. This is a much more extended and open palm shape. The fingers are extended straight from the hand and left a bit open. The thumb is extended and abducted away while being held straight. The index finger is often raised a little higher than the other fingers. The palm surface becomes concave in this position, like a lotus petal or willow leaf. This hand shape is best used for grappling type fighting. The ability to catch and grab on to incoming strikes and then being able to manipulate the opponents joints is a major advantage afforded here. The concave shape of the palm helps to obtain good grip and the extended fingers help brace and keep the fingers safe from jamming while the hand is moved fast among clothing etc.
Claws:

Claws are the next category. A claw is very much like a palm except that the fingers are curved in ward. The fingertips are positioned to transmit much of the force from the hand. It too is an intuitive action, clawing at things when they are overwhelming us or we feel trapped. Claw shapes have much of the same variations as do the palms, with finger spacing, position of the thumb, and shape of the hand being the altered characteristics.
The primary training conceit is that the claws train grips, holds, and locks within solo sets. The theory is that by repetitively assuming these claw shapes, specific types of grips that are used in the parent style will be trained. The mechanics of the claws do bare this out. By assuming a claw shape, the irradiation patterns for the arm can start to be felt without closing the hand all the way. Since, when one is grappling, they are not so much as making a fist but exerting force with the hand partially open. The relative strength of this grip is governed by a large number of criteria, but, by practicing holding a rigid claw shape with the hand can help pattern and condition the muscle groups needed for stronger and more dynamic grips in wrestling situations.
Claws also serve another purpose, even if it is unstated. The claw shape is another type of hand positing that can help activate the rotator cuff and firm up the hand for impact. Claw shapes, like the Eagle Claw, can and are used as positions suitable for chopping with the ulnar (pinky side), the knuckles and the side of the hand. Curling the finger is allows one to more easily create tension in the hand so that it does not buckle when used to strike a surface. This makes claw shapes a sort of “hard palm” shape that can be used for these types of hits.
Hooks:

Hand shapes that utilize the wrist are the final basic category. These are generally used to hook and trap. They fit in somewhere between grappling and striking and they can be used in both situations. Most hook type hand shapes use the “pinch” action of the hand. The fingertips are brought together in some fashion, either all touching or selected fingertips touching and the other folded out of the way. Often times, these handshakes are associated with a specific movement of the hand wrist. The action of rolling the wrist and bringing the finger tips together or pinching the palm of the hand is the basis for many escapes from wrist holds.
The hook shape is one of the most misunderstood of the hand shapes. Since the wrist is often left loose and reactive, some will complain that the positing of the wrist is a risky one to assume. From an injury prevention sense. But this idea is based on the misunderstanding of where and when the force is applied in live use and what is best way to train that when no outside resistance is present. Hooks and hook actions depend not on the hand or fingers themselves, but rather, the space and surfaces of the wrist where it joins with the ulna and radius bones in the arm. These bones have large head that have a fair amount of strength and help support the wrist that is hyper mobile. The hand is usually just along for the ride as far as contact. But the position of the hand and fingers is important to pulling off techniques using the hook shape.
Striking with the hook also, is not what most folks thin about right away. Most assume that you strike with the finger tips in such hand shapes. Although that is possible, your level needs to be fairly high to accurately hit small targets like pressure points and cavities like the eye or carotid artery with only the tips of your fingers. More useful is striking with the superior side of the wrist (the top). The bone process that is formed by the Lula and radius bones is a very strong joint capable of withstanding a good deal of impact. The danger comes in making contact with the hand instead of the wrist. But as long as the joint its self is not making contact, there is no force on the wrist joint that can proceed stress on the joint. Styles like monkey, mantis, and southern styles tend to use the wrist more inter methods.
Hybrid Forms
The above are the basic shapes that are used. There are also many hand shapes that are a combination of these basic hand shapes. These can vary considerably from style to style and for what their intended purpose is. They are shapes that are transitional. They often posses qualities of two or more basic hand shapes, or are used to train multiple responses and actions.
Conclusion
The basic shapes presented here are the starting point for a more expansive taxonomy of hand shapes that occur across multiple styles and time periods. The names change, the expression may evolve, and the application can expand. The mechanical and neuromuscular things that hand shapes produce are very specific and will be looked at separately for each basic shape. An understanding of the biomechanics and tactical uses of these hand shapes can give us great insight into what they can be used for. While their original intent and design might be lost to the sands of time, using our modern methods and honest sparring, we can see that there are benefits from hand shapes that most will not be aware of, even though they are still receiving those benefits.