Twisting a punch
Intro
In a full-twist martial arts punch, the punch begins with the fist at the hip with the palm upward. The fist then drives forward, centered in front of the body. As the punch extends, the fist rotates inward 180 degrees, ending with the palm downward. In a three-quarter-twist punch, the fist also begins at the hip with the palm upward. As the fist drives forward, instead of being centered in front of the body, it is aimed slightly inside the line of the shoulder. As the punch extends, the fist rotates inward about 135 degrees, ending with the thumb side tilted slightly upward.Background of the twist
Some martial art styles use the full-twist punch, some use the three-quarter-twist punch. Of the martial arts that use the twist punch, some only teach the full-twist punch to color belts and the three-quarter-twist punch is only taught to black belts. The reason for these differences in teaching is because the full-twist punch is more traditional, while the three-quarter-twist punch is more practical.Some researchers believe the full-twist punch was created to make it safer to train young people. When the martial arts began to gain popularity and more children began training, some instructors tried to tone down the more dangerous techniques, so they used the full-twist punch for children and beginners and reserved the three-quarter-twist punch for the advanced students.
Another possible reason for the development of the full-twist punch is aesthetics. Philosophically, the martial arts are involved in the development of character. Many styles that are based on the do (way) of the martial arts have a strong sense of aesthetics. Part of this aesthetic expression lies in the use of horizontal and vertical lines. Whereas jutsu (science or skill) types of martial arts tend to use diagonal lines. For example, in iaido (a do type art), the sword is most likely to be drawn to execute a horizontal cut followed by a vertical downward cut, while in battojutsu (a jutsu type art), the draw-cut is more likely to be a diagonal upward slice, followed by a diagonal downward blow. Likewise, in taekwondo (a do type art), the knife hand strike is performed in a horizontal slicing motion, while in jiujutsu, the knife hand is performed in a vertical downward chopping motion. Similarly, the full-twist punch uses horizontal and vertical lines, while the three-quarter-twist punch uses diagonal lines.
While executing the full-twist punch, the forearm muscles are fully stretched and fully contracted sequentially. In the three-quarter-twist punch, the forearm muscles only work to the point of greatest structural equilibrium. This means that the full-twist punch moves the forearm muscles through a greater range of motion than does the three-quarter-twist punch. Also, the alignment of the full-twist punch to the center of the body increases the range of motion of the chest and shoulder muscles; the pectoral muscle is more fully contracted, and the lateral deltoid is more stretched. As a result, the centered, full-twist punch is a better form of exercise than the off-centered, three-quarter twist punch. Therefore, to minimize the risk of injury, only use the full-twist punch should when performing patterns or drills; only use the three-quarter twist punch when punching a heavy bag or during breaking.
Research
In 1992, Ralph Buschbacher, M.D., a 7th-degree black belt in ryukyu kempo and a clinical associate professor in the Department of Physical Medicine and Rehabilitation at the Indiana University Medical Center in Indianapolis, Indiana, conducted cadaver studies to understand the physiology and mechanics of punching. He found that the three-quarter-twist punch best fits the anatomy of the forearm in handing the stress of punching. The following paragraphs discuss some of the factors involved in punching.Bone factors
The forearm has two bones: the thick radial bone and the thinner ulna bone. They are not straight; they are curved so they may wrap around each other to allow the hand to rotate from a palm-up to palm-down position. When punching a solid object, these bones are located between the resistance of the target at the fist and the driving force of the body at the elbow. As a result, when under these stresses, they bend away from each other.Because the ulna is thinner than the radius, it bends more easily and more extremely, producing uneven support at the wrist. However, the body compensates for this unevenness. Between the radius and ulna is a thin, but tough, connective tissue called the interosseous membrane. As the bones bow apart under stress, the membrane is drawn tight, transferring the stress between the two bones to keep them from bowing further and maintaining the structural integrity of the forearm. The force of the punch is distributed over the length of both bones so there is virtually no loss of power or injury. However, the interosseous membrane does not transfer force laterally; it only transfers the force diagonally between the bones.
The radius is quite thick near the wrist but thin near the elbow, while the ulna is thin at the wrist and thick near the elbow. The angle of the interosseous membrane ensures that the weaker portions of each bone attach to the thicker portions of the other bone. And finally, the angle of the membrane is designed to work with the natural stress alignments along the arm when a punch is delivered, which is typically force generated along the line of the radius. The pressure on the radius will cause it to move back slightly, but the angle of the membrane works to keep the bone in place and transfers the forces without any play or slack. This means one should be careful not to punch strongly with the middle, ring, and little fingers because they direct the stress of the punch along the thinner ulna.
During a full-twist punch, the ulna and radius wrap around each other, which means they collapse onto each other and the connecting membrane is folded between them. When the membrane is slack, it cannot support the structure of the forearm bones, so they bend apart and shift upon impact, producing unequal forces in the wrist that results in a loss of punching power and a risk of injury at the weakest areas of the bones. Conversely, during a three-quarter-twist punch, the position of the bones maintains optimal tension in the membrane throughout the movement.
Muscle factors
The muscles of the forearm are also important when punching. The ones that turn the forearm into the palm-up position are called supinator muscles; the ones that turn the palm down are called pronator muscles. The two oppose each other.If the fist is turned fully palm upward, the supinators are completely contracted and the pronators are completely stretched. Likewise, when the palm is turned downward, as in the full-twist punch, the pronators are fully contracted and the supinators fully stretched. In the three-quarter-twist punch, the pronators and supinators are equalized, each being approximately in the middle of its respective range of motion. The result is a muscular balance that contributes to the overall stability of the forearm. In contrast, at the end of the full-twist punch, the supinators are fully stretched and unable to balance the contraction of the pronators. Since these muscle groups help support the wrist, their unbalanced state increases the likelihood of the fist buckling on impact.
Skeletal factors
As mentioned earlier, the full-twist punch lines up with the center of the body, while the three-quarter-twist punch is aligned just inside the shoulder. The reason for the three-quarter-twist punch's alignment is skeletal mechanics.If you watch a full-twist puncher strike a board, the person will align the fist and shoulder with the board. People instinctively know this is the way to get the most power into the punch. Thus, the off-center alignment used in the three-quarter-twist punch is best for hitting with power. Its ideal skeletal and muscular alignment means that more energy can be transferred to the target with less likelihood of injury to the puncher.
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