The one inch punch had half the force of Jamie’s punch, and the three inch punch had two thirds the force.

No feat of martial arts is more impressive than Bruce Lee's famous strike, the one-inch punch. Forget all those broken boards and crumbled concrete slabs. The Hakka and Fujian Arts …
From a … The force from his legs enables his hips to twist faster, "which, in turn, lurches the shoulder of his … People watch Bruce Lee movies, and then they look into the history Little Dragon, and when they see the famous Bruce Lee Punch their jaws drop and they think it can only be done by a super human.

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Bruce when lee least one-inch the punch, man leastflew. Anthony, who was trained in the use of the one inch punch, performed it.

The one inch punch he learned is from Wing Chun and Wing Chun received it from the Yong Chun White Crane Fist Style. The Bruce Lee One Inch Punch has taken on mythic proportions. Anthony further demonstrated the power of the punch by using it to break only the last of three wooden boards, a feat that Jamie was unable to match.

Rose explained, "When watching the one-inch punch, you can see that his leading and trailing legs straighten with a rapid, explosive knee extension."