Brain scans of karate experts have revealed distinctive features in the structure of white matter which could be linked to their ability to punch powerfully from close range.
Researchers from Imperial College London and University College London (UCL) looked for differences in the brain structure of 12 black belt karate experts with an average of 13.8 years’ experience and 12 controls of a similar age who exercised but had no martial arts experience. Researchers tested how powerfully the subjects could punch, restricting the distance to 5cm to enable them to make useful comparisons. The speed of their movements was captured by infrared markers on subjects’ arms and torso.
The karate group punched harder, and the power of their punches seemed to be down to timing – the force they generated correlated with how well the movement of their wrists and shoulders were synchronised.
“Most research on how the brain controls movement has been based on examining how diseases can impair motor skills,” said Dr Ed Roberts from Imperial College London. “We took a different approach, by looking at what enables experts to perform better than novices in tests of physical skill.
“The karate black belts were able to repeatedly coordinate their punching action with a level of coordination that novices can’t produce. We think this ability might be related to fine tuning of neural connections in the cerebellum, allowing them to synchronise their arm and trunk movements very accurately.”
Brain scans called diffusion tensor imaging (DTI) showed structural differences in the cerebellum and primary motor cortex – know to be involved in controlling movement. Differences in the cerebellum correlated with the synchronicity of the subjects’ wrists and shoulder movements when punching. The signal also correlated with the age at which the karate expert began training and their total experience of the discipline.
“We’re only beginning to understand the relationship between brain structure and behaviour, but our findings are consistent with earlier research showing that the cerebellum plays a critical role in our ability to produce complex, coordinated movements,” said Roberts, lead author of the study in Cerebral Cortex.