Heading Ball Too Often May Affect Balance Control

Soccer heading may cause balance problems, according to a preliminary study, that will be presented at the American Academy of Neurology’s Sports Concussion Conference in Indianapolis July 20 to 22, 2018. 

“Soccer headers are repetitive subconcussive head impacts that may be associated with problems with thinking and memory skills and structural changes in the white matter of the brain,” said study author John Jeka, PhD, of the University of Delaware in Newark, Del. “But the effect of headers on balance control has not been studied.” 

Twenty amateur soccer players, 10 females and 10 males, with an average age of 22, participated in the study. They were asked how many times they headed the ball in the past year. The number of headers over a year for each participant ranged from 16 to 2,100, with an average of 451 headers. 

For the balance test the players had to walk along a foam walkway with their eyes closed. There were two conditions: with galvanic vestibular stimulation (GVS) and without GVS. The stimulator acts on the nerves that send messages from the balance system in the inner ear to the brain, thus it can make you feel like you are moving although you are not.  

The results showed that players with the largest number of headers had vestibular processing and balance recovery problems.  

“Soccer players must have good balance to play the game well, yet our research suggests that headers may be undermining balance, which is key to all movement, and yet another problem now linked to headers,” said study author Fernando V. Santos, PT, of the University of Delaware. “It is important that additional research be done to look more closely at this possible link with balance and to confirm our findings in larger groups of people.” 

However, the study, supported by the National Institutes of Health, is limited by the fact that the participants relied on memory when reporting how many times they headed the ball.  

Earlier this year, in Frontiers in Neurology, was released a study that involved 308 amateur soccer players ranging in age from 18 to 55. 

Researchers found that the players who headed the ball most often had lower performance on tests of psychomotor speed, attention and memory, but accidental head impacts did not influence cognitive test performance. 

“The focus in terms of head injury in sports has really been on concussions and recognized symptomatic impacts to the head, typically due to players colliding with each other or falling down,” said lead author Dr. Michael Lipton of the Albert Einstein College of Medicine of New York City.  

In fact, the small, but repetitive impacts may cause long-term damage to the brain.  

“I think that’s really the key message – that impacts to the head matter even when, at the individual impact level, they may not seem to be causing an immediate problem.”  

“What we’re really looking at here is something that is a subclinical effect and the open question, which remains to be answered by more research, is how much of this does it take to cause a permanent effect? And that’s not known yet,” Dr. Michael Lipton said.  

Yet, this study had the same limitation, the memory of the soccer players.  

“As a researcher who has published in this area and as a long-time soccer player who played in college and continues to play as an adult, I know first-hand that most players do not accurately recall heading exposure. Most likely, players over estimated their exposure to heading and lifetime head injuries,” said Anthony Kontos, research director for the UPMC Sports Medicine Concussion Program at the University of Pittsburgh. 

Whether or not heading the ball may cause long-term damage to the brain still remains a question. However, brain is a delicate structure and it is better to stay on the safe side. Children under 11 have already been banned from heading in the United States since 2016, and UEFA may take the same measure.