Brain Power, Not Muscle Strength Related To Force Of Karate Punch

Connie K. Ho for — Your Universe Online

Brain scans of karate experts recently showed distinctive features. Researchers believe that the images show how the ability to punch for black belts and karate novices could be related to a certain feature in the brain.

The researchers, hailing from Imperial College London and University College London, discovered differences in the structure of the connection between brain regions, otherwise known as white matter.

To begin, previous studies looked at how the force of a karate punch is due to brain control of muscle movement rather than muscular strength. The new study, recently published in the journal Cerebral Cortex, examined the differences in brain structure of 12 karate practitioners, each who were ranked at black belt level and had an average of 13.8 years of karate experience. They were compared to twelve other individuals who exercised regularly and were of a similar age, but who did not have any previous marital arts experience.

“Most research on how the brain controls movement has been based on examining how diseases can impair motor skills,” commented lead author Dr. Ed Roberts, researcher at the Department of Medicine at Imperial College London, in a prepared statement. “We took a different approach, by looking at what enables experts to perform better than novices in tests of physical skill.

The researchers looked at the punching power of each of the subjects. They compared the novices to the experts by having each punch from a short range of about five centimeters. The subjects each wore infrared markers on their arms and torso to record the speed of each movement. Based on the findings, the karate group punched harder and the power of the punches seemed to be due to timing. The force of the punch was parallel to the synchronization of their wrist and shoulders in completing the movement.

“The karate black belts were able to repeatedly coordinate their punching action with a level of coordination that novices can´t produce. We think that ability might be related to fine tuning of neural connections in the cerebellum, allowing them to synchronize their arm and trunk movements very accurately,” explained Roberts in the statement.

Apart from measuring the force of the movement with the markers, the scientists also studied brain scans that demonstrated how microscopic structures in specific parts of the brain could be different between the two groups of participants. Regions of the brain are made up of grey matter of the main body of nerve cells as well as white matter made up of bundles of fibers that send signals from region to region. The study utilized diffusion tensor imaging (DTI), scans that can find structural differences in the white matter of the cerebellum and the primary cortex. In particular, the primary cortex controls movement of the body.

“We´re only just beginning to understand the relationship between brain structure and behavior, but our findings are consistent with earlier research showing that the cerebellum plays a critical role in our ability to produce complex, coordinated movements,” noted Roberts in the statement.

With the DTI, the researchers discovered that the differences found in the cerebellum were related to the synchronicity of the participants´ wrist and shoulder movements when punching. The DTI signal was also associated to the subjects´ years of karate experience and the age at which they began their martial arts training. With these two findings, the scientist concluded that the structural differences found in the brain correlated with the punching ability of karate practitioners with black belts.

“There are several factors that can affect the DTI signal, so we can´t say exactly what features of the white matter these differences correspond to. Further studies using more advanced techniques will give us a clearer picture,” concluded Roberts in the statement.