Study Finds That Soccer Players Who Head Balls Often Are More Likely To Have Concussion Symptoms

A recent study finds that Soccer players who head the ball a lot are three times more likely to have concussion symptoms compared to players who do not head the ball often. The researchers suggest that players whose heads were hit in a collision two times or more within a period of two weeks are six times more likely to have concussion symptoms compared to players who did not have any intentional contact or unintentional head trauma, like a ball hitting the head or colliding with another player's knee.

"These results show that heading the ball is indeed related to concussion symptoms, which is contrary to a recent study that suggested that collisions were responsible for most concussions," study author Michael L. Lipton, MD, PhD, of Albert Einstein College of Medicine in Bronx, NY said.

The study was conducted on adult amateur soccer players who played for at least six months in a year on leagues in New York City. The study participants completed an online survey on how often they played soccer during the two weeks prior to the study, how often they had unintentional head collisions and how often they headed the ball, according to Yahoo.

The researchers categorized the players into four groups based on how many times they headed the ball, with the most frequent group heading the ball an average of 125 times in two weeks and the less frequent group heading the ball four times in two weeks.

They were also asked how often they had any symptoms following head contacts. Symptoms can be moderate, defined as moderate pain and dizziness or it could be severe including feeling dazed, inability to continue playing or needing medical attention. The researchers described a very severe symptom to include losing consciousness. They made the questionnaire in a way that allows participants to complete it again every three months.

The total of 222 participants are able to complete 470 questionnaires and 79 percent of them were men. While the male participants had an average of 44 headers in two weeks, the women had an average of 27. Up to 37 percent the male participants reported one or more unintentional head contacts with 43 percent of women reporting same.

Twenty percent of those with head impacts had moderate to severe symptoms, only seven people had very severe symptoms of which six participants reported two or more unintentional head impacts within two weeks, four were in the group that headed the ball the most and three were in the group with the second-most headers.

The researchers stated that those in the group with the most headers were three times more likely to have symptoms than those who headed the ball the less often. The players with two or more unintentional impacts were six times more likely to have symptoms than those with no unintentional impacts. The result is based on how often the players headed the ball.

However, participants with one unintentional impact were also three times more likely to have symptoms than those with no unintentional impacts as the relationship between both headers and unintentional impacts remained the same after the authors adjusted for other factors that could influence the risk of concussion including a history of previous concussions, age and sex, according to Science Daily.

Lipton said one limitation of the study is that its findings are based on information that is self-reported by the participants, which could possibly include errors in recollection. He also noted that the results cannot be generalized to include younger soccer players, teenagers, children or professional players.

He noted that  the findings of the study raises concerns of the long-term effects that result from heading the ball frequently even though further study is needed. The researchers published their findings in the February 1, online issue of Neurology, the medical journal of the American Academy of Neurology.