Bruce Lee – One Inch Punch: Scientific Evaluation (Part 2): Between Reality and Fantasy

Lee punch 3At the beginning, I admit that Bruce Lee (born in November 27, 1940 –July 20 1973) was an amazingly phenomenal person who helped for increasing the popularity of martial arts all over the world by his performances of combined martial arts.

Lee was born in Chinatown San Francisco to the parents from Hong Kong. Lee moved to the United States at the age of 18 to receive his higher education at University of Washington in Seattle. It was during this time when he began teaching martial arts.

He is noted for his roles in the following movies; The Big boss (1971), Fist of fury (1972), Way of the Dragon (1972), and Enter the Dragon (1973). With these movies Bruce Lee became an iconic figure known throughout the world.

He trained in the art of “Wing Chun “. Later combined his other influences from various sources in the spirit of his personal martial arts philosophy which he named, Jeet Kune do, The way of the intercepting fists. Lee held dual nationality of Hong Kong and the United States.

Lee portraitLee began teaching martial arts in the United States in 1959. Even though he called what he taught “Bruce Lee Kung fu”, it was basically his interpretation of Wing Chun.

Lee opened his first martial arts school named the Lee Jun Fan institute in Seattle. Lee dropped out of college in the spring of 1964 and moved to Oakland to live with James Yimm Lee. James Lee was twenty years senior to Bruce Lee and a well-known Chinese martial artist in the area. Together they founded the second Jun Fan martial art studio in Oakland.

James Lee was also responsible for introducing Bruce Lee to Ed Parker American martial arts and organizer of Long Beach International Karate Championships where Bruce Lee was later discovered by Hollywood. By the invitation of Ed Parker, Lee appeared at the Long Beach International Karate Championship in 1964. One of the feats he performed was the repetition of two finger push-ups (using the thumb and the index finger of one hand) with feet at approximately a shoulder width apart.2 finger push up

At this event, he also performed the “one inch punch” which is a punching technique from Chinese martial arts performed at a range of 0 to 15 cm. This one inch punch became well known because of this actor and the martial artist, Bruce Lee. It was to demonstrate Lee’s unique ability in punching technique thus proving the expertise in the martial arts. Lee stood upright with his right foot forward with knees bent slightly in front of a standing partner. Lee’s right arm was partly extended and right fist approximately one inch away from the partner’s chest. Without retracting his right arm Lee then forcibly delivered the punch to his partner while maintaining his posture sending the partner backwards and he fell into a chair placed behind him to prevent injury from falling onto the floor.

1 inch punch

1 inch punch 2


The one inch punch is present in many styles of southern Chinese martial arts. As a general rule southern Chinese martial arts specialize mostly on the hand techniques from very close quarters with rather short stances. As opposed to northern Chinese martial arts that focus more on kicking techniques from medium to long distances.

The southern styles martial arts base their fighting concept on frequently fighting nose to nose distance with their opponents, thus they have to learn a way to punch effectively even they are almost touching their opponent.

The one inch punch is a skill which generates explosive power from close distance (one inch or less). This burst effect skill has been common in Neijia form.

When performing this one inch punch the practitioner stands with his fist very close to the target (the distance depends on the degree of the practitioner’s skill, it is usually from 0-6 inches).

They say a quick movement of the wrist produces the force needed, the wrist is held with the knuckles facing out on horizontal axis the wrist is then moved up and a strike is produced with the bottom two knuckles.

Bruce Lee learned that technique from Wing Chun training in Hong Kong.

In the television show Myth busters episode (The one inch punch) technique was tested quantitatively using force gauge. For comparison it was matched against a conventional punch thrown with full wind up by Jamie Hyneman.

The one inch punch was delivered by Anthony Kelly a martial arts expert and instructor who had learned that 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 host deemed it plausible as a combat technique if the user had proper training and experience.

The one inch punch is also often used in martial arts as a training exercise to show how to generate additional power at the end of a conventional punch.

In the television show, Stan Lee’s Superhuman demonstrated his one inch punch on a crash test dummy. The testing showed it was 1,7 times more injurious than a 30 mph car crash with modern safety features.Osaka Egypt

(JKA’s Masaharu Osaka performing Sochin kata in 1983 Championship in Egypt, photo right)

The scientific points

The kinetic energy of an object is the energy that it possesses due to it’s motion.

■Having gained this energy during its acceleration the body maintain this kinetic energy unless its speed changes.

■Mass in physics is a property of a physical body which determine the strength of its mutual gravitational attractions to the other bodies, its resistance to being accelerated by a force and in the theory of relativity gives the mass-energy content of a system.

■Mass is not the same as weight even though we often calculate an object ‘s mass by measuring it’s weight with a spring scale instead of comparing it to known masses.Egyptian picture

It is defined as work needed to accelerate a body of a given mass from rest to its stated velocity.

To explain this an object on the moon would weigh less than it would on earth because of the lower gravity but it would still have the same mass.

Mass is described as the amount of an object.

Newton’ second law of motion:

If a body of fixed mass (m) is subjected to a single force (F) its acceleration is given by F/M.

A body ‘s mass also determine the degree to which it generates or is affected by a gravitational field.

The Rotational kinetic energy depending on rotation about an axis and for a body of constant moment of inertia is equal to the product of half the moment of inertia times the square of the angular velocity.Galileo

KE = 1/2 M V2

KE (kinetic energy)

M (mass)

V2 (square of velocity)

The standard unit of the kinetic energy is the joule.

If we look for a comparison between the one inch punch & straight punch “choku zuki ” we found that:

The one inch punch is a combination of pushing and hitting the target at the same time because it didn’t take the suitable pass way from the point of starting until the target.

of course there are kinetic energy are emitted and this appears from the result of quantitative testing of the one -inch punch which delivered by Anthony Kelly (153 pounds).

Also the position of the fist and the site of knuckles which (little finger and ring finger) will not give the maximum effects because the transmission of force will not go through the knuckles of ( index finger and middle finger) which supported over the trapezium, trapezoid and capitate on the upper row of the carpal bone which supported by scaphoid lunate which in turn supported by the radius bone on the forearm.

But in case of Bruce Lee he used the knuckles of (the little finger & the ring finger) which are not completely supported by the carpal bone (triquetrum being unsupported over the ulna)and there is a space.

It is clearly appear from the photo (below left).

To make a good striking blow, you must correct the attitude of the fist through the knuckles of the index and the middle finger which supported in the direction of the radius, and this for complete transmission of force (illustration below right).

Lee punchHand bones structure

But for straight punch “choku- zuki “, the kinetic energy which emitted according to the distance to the target and the rotation make the rotational kinetic energy is to generate tremendous amount of impact force at the target.

kinetic Energy = 1/2 M v2Otto

Naka 2WKF


JKA Naka Tatsuya (above left), Rafael Agayev 4 time WKF world champion (above middle), Wayne Otto World Champion from England (above right)


1) One inch punch has emitted force not completed because of the distance is short and not enough to go and complete the pass way of the strike.

2) So it appears as it was a strong pushing technique.

3) Straight punch “choku -zuki “has greater effects of damaging because it has higher rotational kinetic energy.

4) Maybe Bruce Lee appeared in a time when the karate was not well known and there was no championship like today. The appearance of Tatsuya Naka, Wayne Otto and Rafael Agayev then might have made a difference in the impression of Bruce Lee.

5) There was no doubt that Bruce Lee had excellent physique.

6) It is also true that Bruce Lee increased the popularity of karate and Asian martial arts.


This part was written by Dr. Ashraf Ragab.Ragab portrait

Pharmacist B.Sc.Ph.Ph.Ch.

Faculty of pharmacy Cairo University

Date of graduation May 1983 with general grade “very good”

Sport injury specialist with excellent grade in 1/7/1998 from Olympic Academy of Athletic leaders

Karate examiner of Egyptian karate Federation from 11 years

Manager of karate section of Bank Ahly club

Lecturer at the Egyptian Karate Federation for :

Karate Athletic injuries & drug doping

Karate movement science

The highest ranking student degree at Olympic Academy of Athletic leaders with excellent grade in all branches .


1 Grant’s Atlas of anatomy

2 Bruce Lee: Wikipedia

3 Kinetic energy: Wikipedia

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