Results were published Monday, April 20, in Optometry & Visual Performance, a jointly published open-access journal of the Optometric Extension Program Foundation, College of Optometrists in Vision Development and Australasian College of Behavioural Optometrists.
“Football is a complex skilled sport with the need to integrate sensory input to be successful, and our opinion is that vision plays a key component,” says Joe Clark, PhD, a professor in the UC Department of Neurology and Rehabilitation Medicine who was the study’s corresponding author. “But little to no emphasis is placed on prevention or training to reduce the risk of traumatic brain injury (TBI), which includes concussions.
“So far, improved helmets and concussion mitigation strategies have been ineffective,” Clark adds. “What we need is a strategy that can decrease the risk of injury from collisions and is easily adoptable by coaches and medical practitioners. We hypothesized that vision training would significantly reduce both practice and competition concussion incidence in football.”
UC’s team plays at college football’s highest level, the National Collegiate Athletic Association’s (NCAA) Football Bowl Subdivision. The Bearcats are members of the American Athletic Conference.
“Our program goal is to improve the safety and health of our student-athletes at the University of Cincinnati,” says Bob Mangine, UC’s associate athletic director for sports medicine and one of the study’s co-authors. “With increasing concern over the lasting effects of concussions, our team is making every effort to both reduce our student-athletes’ risk and improve their safety.
“The UC Department of Athletics is fortunate to have a dedicated team of clinicians and researchers who are continuing to address this medical condition and attempting to minimize its effect on current and future athletes everywhere.”
Clark and his colleagues incorporated vision training into the preseason football camp schedule of all UC football team members in 2010, giving them four seasons (2010–2013) to compare to four previous seasons (2006–2009) without vision training. (The training continued in 2014, Clark says, adding in a note to the study that the team had three diagnosed concussions—making it five years with three or fewer concussions per season since the initiation of vision training.)
Intense vision training was performed during football camp at the Higher Ground Conference and Retreat Center in West Harrison, Indiana, typically conducted for two weeks immediately prior to the start of the season. Players had about 40 minutes of structured vision training per day for six or seven days a week.
Numerous vision training methods were used, including a Dynavision D2 light board, an eye-hand coordination device that tests and improves visual motor skills by using small board-mounted target buttons that light up randomly. The user is presented with a stimulus and has to locate the light and strike it with the hand as quickly as possible.
Additional vision training methods included a tachistoscope, which trains the brain to recognize images faster, pinhole glasses, strobe glasses and pitch and catch routines that were made progressively more complicated.
The vision training was designed to improve vision processing, speed of processing, eye hand coordination, visual fields, ocular motor performance and overall awareness. The drills were done as part of regular weight and conditioning training with the players going through circuits of exercises. During the training, the complexity and demands of the training increased to be challenging and demanding. Many of the vision training methods produce quantitative scores; the scores were recorded and high scores were posted and challenged. (Making the performance a competition improves participation and performance, Clark says.)
During the season itself, a maintenance phase of vision training was initiated, exclusively using the Dynavision D2.
When data on concussion incidence were evaluated, a statistically significant lower rate of concussion was noted in players who received vision training (1.4 concussions per 100 game exposures) compared with players who did not receive the training (9.2 concussions per 100 game exposures). The decrease in injury frequency in competitive seasons with vision training was also associated with a concomitant decrease in missed playing time. (All team members for each season used the same helmet models from the same two manufacturers.)
In other words, according to Clark, the average annual concussion rate fell by over 80 percent from pre-vision training years (2006 to 2009) to post-vision training years (2010 to 2013).
“We believe that the vision training we performed is broadening the athlete’s field of awareness, or functional peripheral vision,” says Clark. With that additional information, they can react faster to their changing environment and avoid injury-causing collisions.” This was supported by data from the study showing improved peripheral awareness reported.
Clark says empirical evidence indicates that the vision training led to an improvement in the control and fidelity of the extra- and intra-ocular muscles of the eyes. Therefore, he says, the eyes were able to more precisely “focus” on a point, remain there and give the brain better information from peripheral visual fields.
“This, to an extent, may be what the athletes use during competition to increase awareness of where that point is in physical space,” he says. “Many coaches have told their players to ‘use’ their peripheral vision. What this vision training did was train our athletes to improve their peripheral vision.”
Clark notes that while the study provides important preliminary data, the small sample size indicates that interpretation of the results should be taken with caution. He says further large-scale clinical trials are needed to confirm the effects noted in this preliminary study.
Funding was provided by the National Institute of Biomedical Imaging and Bioengineering, an institute of the National Institutes of Health, and Geraldine “Ginger” Warner, a UC Board of Trustees member and retired attorney.