Heads Up: Research on the Concussion Gender Gap for Soccer Players-Claire Ganley

 

            During the second weekend of July in 2015, my club soccer team and I competed in the National Premier League National Finals soccer tournament in Westfield, Indiana. After the first two days of the tournament, we had qualified to play in the semifinal match. Toward the end of the second half, I had to make a slide tackle to stop a goal scoring opportunity for the opposition. As I contacted the ball, my opponent’s cleat made contact with the side of my head. I continued to compete for the remainder of the match, despite my continuous pounding headache. Once the game was over and my adrenaline had completely worn off, that pounding headache grew substantially worse. Growing up, I suffered from migraines until about twenty-four hours after playing soccer games. I contributed this to the fact that I was mentally taxed from hyper fixating on the match. So, this nagging headache from the semifinals did not lead me to believe that anything was out of the ordinary.  

            A couple of days went by, and the symptoms persisted. By this time, my mom and I recognized this as a major concern. We made an appointment with a neurologist who suggested that I was expressing symptoms of a traumatic brain injury. I was ordered to stop athletic activities and limit my exposure to electronic devices until all concussion symptoms subsided. After three months of no athletic activity, I was cleared to begin the return-to-play protocol. Within five months of my return to play, I sustained another concussion.

            This most recent season playing on the Stevens Varsity Women’s Soccer Team, three teammates were required to sit out of training and matches because of concussions that they sustained while playing soccer. Meanwhile, one individual on the Stevens Varsity Men’s Soccer Team suffered a concussion during the fall season. Because of the disparity between the number of males and females that suffer concussions while playing soccer and because of my own personal experience suffering from concussions, I was motivated to research the extent of the concussion gender gap for soccer players.

            When discussing sports-related concussions, American football is generally the sport that receives all the concern. Most of the research that has been conducted to study the effects of sports-related concussions involve football players. Concussion studies involving female soccer players are limited despite the prevalence of concussions sustained during soccer matches and practices. A study conducted by researchers at the University of North Carolina at Chapel Hill (2019) reported that 9542 concussions were sustained in 20 different high school sports by participating schools during the two-year study period. Girls’ soccer was reported as the sport with the second highest number of concussions resulting from participation. Even though high school football had the largest number of reported concussions (4183), the prevalence of concussions in high school girls’ soccer (1055) is important to recognize. In this study, it was determined that 10.40 concussions are sustained by football players for every 10,000 athletic exposures (AEs), whether that be practice or games. Girls’ soccer had the second highest rate of concussions at 8.19 concussions for every 10,000 athletic exposures. Even though football players sustain concussions more frequently than girls’ soccer players, it does not discount the prevalence of the issue.

            Most multisport reports on sports-related concussions focus on the statistics of boys’ sports, discounting the rifeness of concussions in girls’ sports. Boys’ soccer concussions tend to be discussed more frequently than girls’ soccer concussions, despite the evidence that girls’ soccer players sustain more concussions than boys’ soccer players. According to that study conducted by researchers at the University of North Carolina at Chapel Hill, boys’ soccer players accounted for 5.53% of total concussions reported by the high schools, whereas girls’ soccer players accounted for 11.06% of all reported concussions. Even though the boys’ soccer players had more athletic exposures (1,480,666) than girls’ soccer players (1,287,732), the rate of concussions sustained by the girls’ soccer players (8.19/10,000 AEs) was more than double the rate of concussions sustained by boys’ soccer players (3.57/10,000 AEs). Girls’ soccer players suffer about 2.3 concussions for every concussion suffered by a boys’ soccer player. The same study also suggested that the sport with the largest concussion gender gap (female concussions: male concussions) was soccer (2.30:1), followed by basketball (2.28:1). All sex-comparable sports that were studied had higher rates of concussions for females than males, raising the question as to why there is such a significant concussion gender gap.

            Even though there is evidence that suggests females are more likely to report symptoms of a concussion than males, the disparity between the number of concussions sustained by females and males is cause for concern. One of the reasons why females suffer from soccer-related concussions at a higher rate than males is because of the biomechanical differences between men and women. Research conducted by Anita Vasavada, a professor at Washington State University possessing interest in biomechanics and neural control of the musculoskeletal system, concludes that the neck of a female is both smaller and weaker than males. Furthermore, Vasavada’s research found that females’ necks are 20% weaker in extension and 32% weaker in flexion than males’ necks. On average, the neck of a female is between 9 and 16% smaller than a male’s neck, whereas the head of a female is only 3-6% smaller than a male head. This research suggests that females will experience an increased incidence of whiplash injury than males since a female neck is weaker and smaller but still carries a head that is not much smaller than a male’s head. Vasavada’s research also concludes that the cervical spine of a female between the C3 and C7 vertebrae is significantly smaller in the anterior-posterior direction than that of a male. This research is significant to the study of the concussion gender gap in soccer because it can be used to explain why a female is more likely to sustain a soccer-related concussion from contact with an object than a male.

A skill that is well-known for causing soccer-related concussions is heading the soccer ball. When executing this skill, a player attempts to redirect a ball in the air by contacting it on the hairline. A study conducted by Abigail Bretzin, an athletic trainer and postdoctoral research fellow at the University of Pennsylvania studying sport-related concussions, found that female soccer players are more likely to sustain a concussion by equipment contact (contact with a ball or goalpost) than any other method of sustaining the injury. 41.9% of female concussions were a result of contacting the ball or goalpost. For males, only 31.7% of concussions were sustained from contact with an object. Since females are more susceptible to whiplash because of their smaller and weaker necks, female soccer players suffer from more concussions sustained by heading the ball than males. Bretzin’s study suggests that the concussions sustained by females are slightly more severe than the concussions sustained by males. On average, males return to play soccer ten days after the diagnosis with a concussion, whereas females return to unrestricted activity after twelve days. Players are required to present no symptoms of concussions to begin the return-to-play protocol that weans players back into the sport. Females suffer from symptoms of the concussion two days longer than males, suggesting that, on average, her concussion is slightly more severe than his.

With countless studies linking sports-related concussions to negative long-lasting side effects, such as headaches, memory loss, anxiety, and depression, new methods of limiting risk of sustaining a concussion have been researched. As of January 2016, the National Association of Competitive Soccer Clubs (US Club Soccer) implemented its new guidelines for players in 13-U programs and under. Players in 11-U and younger are not allowed to head the ball in practices or games to minimize the likelihood of children sustaining a concussion while playing. US Club Soccer allows for limited heading during training sessions for players in 12-U and 13-U. These players are not allowed to exceed 15-20 headers per week. The implementation of these rules does cause for concern that the players will not have adequate training on the proper heading technique for when they reach the 14-U programs that do not have limitations on heading.

Soccer headgear was created in 2003 to reduce the prevalence of soccer-related concussions. This headgear reduces the severity of a concussion sustained by providing an extra layer of protection between the ball and the forehead of the player. Research conducted the year the headgear was released suggests that when there is more force behind the ball, the headgear can limit more of the force felt by the player. In other words, headgear is more reliable for the more intense blows to the head. From my personal experience playing soccer for the majority of my life, I only encountered one female player who wore the headgear. Commonizing female soccer players wearing headgear can reduce the number of concussions sustained while heading the ball, subsequently reducing the concussion gender gap.

Research conducted by Christy Collins, the President at Datalys Center for Sports Injury Research and Prevention, Inc., concludes that “for every one pound increase in neck strength, odds of concussion decreased by 5%.” To address the disparities between the neck strength of males and females, neck strengthening exercises may possess the ability to lessen the concussion gender gap for soccer players. Examples of exercises that may be used to strengthen neck muscles are shoulder scapular squeezes, wall push-ups, rows, and weighted shrugs. Building muscles in the upper back and trapezius work to strengthen neck muscles.

Both concussions that I sustained throughout my twenty-year soccer career were within one year of each other, toward the end of my middle school years. Once I entered high school, I substituted physical education for a weight room course. Ever since I began lifting weights in my freshman year of high school, I have not sustained another concussion. While it is possible that this is a coincidence, it is also possible that because I gained muscle from weightlifting, I strengthened my neck enough decrease the sensation of whiplash from heading the soccer ball. Integrating exercises and lifts that strengthen neck muscles into training for female soccer players can begin to close the concussion gender gap.

 

Works Cited:

Bretzin, Abigail C. “Sex and Adolescent Soccer Concussion Incidence and Characteristics.” JAMA Network Open, 27 Apr. 2021, jamanetwork.com/journals/jamanetworkopen/fullarticle/2779117.

Collins, Christy L., et al. “Neck Strength: A Protective Factor Reducing Risk for Concussion in High School Sports.” The Journal of Primary Prevention, U.S. National Library of Medicine, Oct. 2014, pubmed.ncbi.nlm.nih.gov/24930131/.

Vasavada, Anita., et al. “Head and Neck Anthropometry, Vertebral Geometry and Neck Strength in Height-Matched Men and Women.” Journal of Biomechanics, U.S. National Library of Medicine, 13 Aug. 2007, pubmed.ncbi.nlm.nih.gov/17706225/.

“Head Injuries.” US Club Soccer, 19 Jan. 2022, usclubsoccer.org/headinjuries/.

Kerr, Zachary Y., et al. “Concussion Incidence and Trends in 20 High School Sports.” American Academy of Pediatrics, 1 Nov. 2019, publications.aap.org/pediatrics/article/144/5/e20192180/38225/Concussion-Incidence-and-Trends-in-20-High-School?autologincheck=redirected.

Naunheim, Rosanne S., et al. “Does Soccer Headgear Attenuate the Impact When Heading a Soccer Ball?” Academic Emergency Medicine: Official Journal of the Society for Academic Emergency Medicine, U.S. National Library of Medicine, Jan. 2003, pubmed.ncbi.nlm.nih.gov/12511322/.

Streifer, Michael, et al. “The Potential Role of the Cervical Spine in Sports-Related Concussion ...” Journal of Orthopaedic & Sports Physical Therapy, 28 Feb. 2019, www.jospt.org/doi/10.2519/jospt.2019.8582.