Boxing at the amateur level is less harmful to the brain than previously assumed, says a new study. Obviously the brain is a sensitive instrument so few statements on repeated blows to the head can be truly conclusive and whether or not a professional boxer like Muhammad Ali contracted Parkinson’s disease at age 40 due to injuries sustained in the ring may always remain unclear.
In the Heidelberg Boxing Study(1), high-resolution MRI data were used to search for tiny changes in the brains of amateur boxers and a comparison group of non-boxers. These changes are most likely precursors for later severe brain damage such as Parkinson’s disease or dementia.
In three of the 42 boxers, microhemorrhages were found, while in the comparison group of 37 non-boxers there were no such changes; however the difference was not statistically significant.
Microhemorrhages could be precursors to Parkinson’s disease and dementia
In boxing, the head is hit at a high speed and with great force. This can lead to shear movement between different brain tissues, resulting in microhemorrhages.
“Injuries of this kind can be detected with the help of a modern MR imaging device with a field strength of 3 Tesla such as is available in Heidelberg,” explained Professor Dr. Stefan Hähnel, chief consultant at the Division of Neuroradiology, Department of Neurology, University of Heidelberg Medical Center, who conducted the study with Professor Dr. Uta Meyding-Lamadé, then chief consultant at the Department of Neurology, University of Heidelberg Medical Center, now Medical Director at Krankenhaus Nordwest in Frankfurt.
It is not known how often the microhemorrhages occur in boxers. They may eventually lead to the destruction of brain cells and deficits such as dementia and Parkinson’s disease. This hypothesis is shared by some working groups. The three boxers in whom changes were found typically had the changes in the frontal or temporal lobes, where the shear forces of blows are strongest.
One disadvantage of the “Heidelberg Boxing Study” was the great range in duration and intensity of amateur boxing. Duration ranged from one to 25 years and intensity from one to 375 bouts with 0 to 12 knockouts. A follow-up study is planned to include professional boxers, in order to assess intensive exposure to blows. The Heidelberg researchers are currently looking for funding for this study.
The study was carried out jointly with National Training Center for Boxing in Heidelberg and the Department of Sport Medicine at the University of Heidelberg Medical Center (Medical Director: Professor Dr. Peter Bärtsch).
(1) Hähnel S, Stippich C, Weber I, Darm H, Schill T, Jost J, Friedmann B, Heiland S, Blatow M, Meyding-Lamadé U: 'Prevalence of Cerebral Microhemorrhages in Amateur Boxers as detected by 3-Tesla Magnetic Resonance Imaging'. Am J Neuroradiol 29 (2): 388-391 (2008) doi: 10.3174/ajnr.A0806