By Dev K. Mishra, M.D., President, Sideline Sports Doc
With advanced brain imaging techniques and brain functional tests, researchers at the Albert Einstein College of Medicine have presented findings from an interesting study that suggests that repeatedly heading a soccer ball increases the risk for brain injury and cognitive impairment. You can read a summary of the study and see a brief video interview with one of the study authors here.
The study authors used an advanced MRI-based imaging technique on 38 amateur soccer players (average age: 30.8 years) who had all played the sport since childhood. They were asked to recall the number of times they headed the ball during the past year. Researchers ranked the players based on heading frequency and then compared the brain images of the most frequent headers with those of the remaining players. They found that frequent headers showed brain injury similar to that seen in patients with concussion, also known as mild traumatic brain injury (TBI).
The interesting part (and somewhat scary) is that by combining the MRI findings, brain functional tests, and number of headers the players recalled in the past year the researchers were able to come up with a threshold for brain injury risk in these adult players. The number: about 1000 headers annually. That number is really not as big as it seems. Let’s say you play 30 weeks out of the year, three times per week. It comes out to about 11 headers per game or practice session. That’s a number easily reached by many defenders and other field players.
The authors then go on to point out some parallels between this study on headers and studies performed on throwing injuries in Little League players that ultimately lead to pitch count rules now adopted by Little League Baseball.
Here’s my take, as a former player, current parent of two soccer players, and current team physician with 18 years of experience:
- This paper, along with other mounting evidence, points to a possible cause-and-effect relationship between repeated headers and mild brain injury similar to a concussion. We need to take this evidence seriously.
- But still, more evidence is needed. We need to study this issue carefully in a large prospective clinical trial involving the youth age groups. This type of study would likely involve multiple study sites, following players from the start of a time period over one or more playing seasons. The baseball studies were like this. They take years to complete.
- My feeling is that if there is a threshold of headers for the younger player, studies will likely show that it is much lower than 1000 headers per year. The young brain is more susceptible to injury than the adult brain.
- My feeling also is that the threshold for female athletes will be lower than male athletes. There is convincing evidence that gender differences exist, with girls/women sustaining concussion with lower forces.
So we’re not ready to assign a “header count” for young soccer players but the youth soccer coach would be wise to structure practice sessions to minimize heading. This study from the Albert Einstein College of Medicine doesn’t give us all the answers but it most surely begs us to ask the tough questions.