The one-inch punch is a punching exercise from Chinese martial arts (kung fu) performed at a range of 0–15 cm (0–6 in). The one-inch punch was popularised by actor and martial artist Bruce Lee. It is designed to improve punching power and technique
The One-inch punch is present in many styles of Southern Chinese martial arts.[citation needed] As a general rule, Southern Chinese martial arts rely mostly on hand techniques from very close quarters (as opposed to Northern Chinese martial arts which focus more on kicking techniques from medium to long distances). Because the Southern styles martial artists were often fighting nose-to-nose with their opponents, they had to learn a way to deal out punishing blows even while almost touching their target.
The one-inch punch is a skill which uses fa jin (translated as explosive power) to generate tremendous amounts of impact force at extremely close distances. This "burst" effect had been common in Neijia forms. When performing this one-inch punch the practitioner stands with his fist very close to the target (the distance depends on the skill of the practitioner, usually from 0–6 inches). A quick movement of the wrist produces the force needed, the wrist is held with the knuckles facing out on a vertical axis, the wrist is then moved up and a strike is produced with the bottom two knuckles. The target in such demonstrations vary, sometimes it is a fellow practitioner holding a phone book on the chest, sometimes wooden boards can be broken.
The one-inch punch was made popular in the west when demonstrated by Bruce Lee at the Long Beach International Karate Championships in 1964. Bruce Lee learned the technique from his Wing Chun training in Hong Kong. He used the art of Wing Chun as his basis of the art he founded, Jeet Kune Do.
In the television show MythBusters episode "The One Inch Punch", the technique was tested quantitatively using a force gauge. For comparison, it was matched against a conventional punch thrown with a full wind-up by Jamie Hyneman. The one-inch punch was delivered by Anthony Kelly, a Martial Arts Expert and Master Instructor who had learned the technique from one of Bruce Lee's students. The conventional punch measured 325 pounds of force while the one-inch punch measured 153 pounds. In the absence of a safe method of testing against a human being, the hosts deemed it "plausible" as a combat technique, if the user had proper training and experience.[1]
The one-inch punch is also often used in martial arts as a training exercise to show how to generate further power at the end of a conventional punch.
In the television show Stan Lee's Superhumans, the Shaolin monk Shi Yan Ming demonstrated his one-inch punch on a crash test dummy. The testing showed it was 1.7 times more injurious than a 30 mph (48 km/h) car crash with modern safety features.[2]
In the Quentin Tarantino directed Kill Bill: Volume 2, the protagonist (Uma Thurman) learns a variation of the technique as part of her training to exact revenge on her would-be killers. She learns to punch through thick planks of wood, from a distance equal to the length of her fingers. She eventually uses the technique to break out of a wooden coffin, after being buried alive.
Biomechanical Breakdown
To understand why the one-inch punch is more about mind than muscle, you first have to understand how Bruce Lee delivers the blow. Although Lee's fist travels a tiny distance in mere milliseconds, the punch is an intricate full-body movement. According to Jessica Rose, a Stanford University biomechanical researcher, Lee's lightning-quick jab actually starts with his legs.
"HIS LEADING AND TRAILING LEGS STRAIGHTEN WITH A RAPID, EXPLOSIVE KNEE EXTENSION."
"When watching the one-inch punch, you can see that his leading and trailing legs straighten with a rapid, explosive knee extension," Rose says. The sudden jerk of his legs increases the twisting speed of Lee's hips—which, in turn, lurches the shoulder of his thrusting arm forward.
As Lee's shoulder bolts ahead, his arm gets to work. The swift and simultaneous extension of his elbow drives his fist forward. For a final flourish, Rose says, "flicking his wrist just prior to impact may further increase the fist velocity." Once the punch lands on target, Lee pulls back almost immediately. Rose explains that this shortens the impact time of his blow, which compresses the force and makes it all the more powerful.
By the time the one-inch punch has made contact with its target, Lee has combined the power of some of the biggest muscles in his body into a tiny area of force. But while the one-inch punch is built upon the explosive power of multiple muscles, Rose insists that Bruce Lee's muscles are actually not the most important engine behind the blow.
"Muscle fibers do not dictate coordination," Rose says, "and coordination and timing are essential factors behind movements like this one-inch punch."
Because the punch happens over such a short amount of time, Lee has to synchronize each segment of the jab—his twisting hip, extending knees, and thrusting shoulder, elbow, and wrist—with incredible accuracy. Furthermore, each joint in Lee's body has a single moment of peak acceleration, and to get maximum juice out of the move, Lee must layer his movements so that each period of peak acceleration follows the last one instantly.
So coordination is key. And that's where the neuroscience comes in.
Martial Arts Neuroscience
In a 2012 study, Ed Roberts, a neuroscientist at Imperial College London, compared the punching strength (at a range of slightly less than 2 inches) between practitioners of karate and physically fit people with similar amounts of muscle who do not practice martial arts.
"The first thing we found was that karate experts can punch much harder than normal, untrained people. Which isn't exactly what you'd call Nobel Prize–worthy work," he says.
But Roberts also discovered that for the karate practitioners, muscle alone didn't dictate strong punches. Rather, when he used motion-tracking cameras to track the puncher's joints, he found that strikes that synchronize the many peak accelerations in one complex move—like Bruce Lee's—were also the most powerful.
BRUCE LEE OWES HIS MASTER FEAT IN PART TO A BEEFED-UP GLOB OF WHITE MATTER
And when Roberts took brain scans of his study's participants, he also found that the force and coordination of each participant's two-inch punch was directly related to the microstructure of white matter—the substance that manages communication between brain cells—in a part of the brain called the supplementary motor cortex. This is important, because this brain region handles the coordination between the muscles of the limbs, which close-range punches rely on. The altered white matter allows for more abundant or complex cell connections in that brain region, Roberts says, which could increase the puncher's ability to synchronize his or her movements.
So Bruce Lee owes his master feat in part to a beefed-up glob of white matter. But that doesn't diminish the grandeur of the one-inch punch one bit. Like his muscles, Lee earned his brainpower the hard way, with many years of practice. Roberts says the white matter changes in his study's participants can be traced to the concept of neuroplasticity—the brain's ability to fundamentally rewire itself to cope with new demands. The more karate experts practiced these coordinated moves, the more the white matter in their supplementary motor cortex adapts.
Of course, neuroplasticity diminishes with age, so it's better if they start young. In the words of an ancient Chinese proverb, "The best time to plant a tree was 20 years ago. The second-best time is now."