Researchers in Denmark and the United States are investigating possible brain injury when soccer players head the ball. This will help NASA and others to evaluate how weightlessness affects intracranial pressure.
What happens to the brain when intracranial pressure increases or decreases?
Researchers and doctors actually know very little about this, and the research is complicated because it requires taking measurements within the intracranial space.
Nevertheless, this question is extremely relevant in space research because weightlessness in zero gravity also strongly affects the brain.
If people can travel to Mars or even further one day, the brains of the astronauts or space tourists need to be protected from permanent damage resulting from long-term changes in intracranial pressure on the long round-trip voyage.
To determine the effect of variation in intracranial pressure, researchers in Denmark have studied soccer players heading a ball. This research reveals that external forces can increase the pressure quite quickly but that it can also decrease rather quickly again.
“My research seeks to determine how gravity affects intracranial pressure. If we discover that the increases in pressure in a zero-gravity environment harm the brain, we need to develop methods to prevent this. Otherwise, people cannot keep their brains healthy during the long voyages in space that may happen soon. Obtaining access to hundreds of astronauts to carry out experiments is obviously not easy, so we needed to investigate pressure increases in other ways, including in everyday scenarios,” explains an author behind the study, Lonnie Grove Petersen, International Researcher, Department of Biomedical Sciences, University of Copenhagen and Professor, Jacobs School of Engineering, University of California, San Diego, USA.
The research has been published in The FASEB Journal.
Investigated pressure increases by asking young men to head a soccer ball
Lonnie Grove Petersen investigated how heading a soccer ball affects the brain.
An average soccer player heads the ball six times during a game, and each blow to the skull has the potential to send shock waves through the cranium and disturb the intercranial pressure.
To investigate this, Lonnie Grove Petersen recruited eight healthy young men to head a soccer ball six times, with the ball being kicked from the same distance with the same force each time to standardise the test.
The researchers examined the intercranial pressure by measuring the frequency across the eardrum. This is an excellent indicator because higher frequency indicates increased intracranial pressure.
Pressure increased but returned to normal after 24 hours
The intracranial pressure increased immediately after the heading trial but returned to normal after 24 hours.
Lonnie Grove Petersen says that this observation is interesting and initially begs the question: why does the pressure increase at all? She is currently investigating this.
“We suspect that the pressure increases because of swelling in the brain that is similar to the swelling when your leg gets hit. But since the brain is enclosed in the intracranial space, the pressure increases. The good news is that it decreases again and is merely a transient increase. It probably does not matter much if trial participants head a ball six times in total, but if you play soccer daily or several times a week, the intracranial pressure increases frequently, although thankfully decreases rapidly again,” says Lonnie Grove Petersen.
Being active is always healthy for the brain
Lonnie Grove Petersen explains that the study is one piece of a puzzle to understand how small blows to the head affect the brain in the long term.
However, she also says that, although heading a ball may appear to harm the brain, at least in the short term, sports and exercising always outweigh inactivity from a health perspective – and this also applies to the brain. People reduce their risk of developing poor memory and other degenerative conditions of the brain later in life if they exercise regularly.
“We are getting closer to understanding which factors generally protect or harm the brain. This is the context for this study, and the knowledge can be used in many fields, including space research and understanding brain injuries,” concludes Lonnie Grove Petersen.