Sports-related concussions (SRCs) continue to serve as a major health concern and one of the most hotly debated topics in sports medicine today. While research surrounding concussion – its incidence, assessment, and recovery – remains strong globally, scientists and medical professionals still lack definitive research on the most effective approaches to rehabilitation for this serious injury. This article explores evidence both for and against physical/cognitive rest post-injury, and discusses newly emerging interventions that offer promise for athletes suffering from SRCs.
Defining the Injury
An estimated 1.6 -3.8 million sports-related concussions occur annually in the United States, and the numbers continue to rise. This growing prevalence, perhaps driven by heightened awareness, led to an updated consensus statement presented at the 6th International Conference on Concussion in Sport in 2022.
The Concussion in Sport Group (CSG) redefined sports-related concussions as traumatic brain injuries caused by a direct blow to the head, neck, or body during sports activities, with forces transmitted to the brain. Experts believe such injury tends to result in a host of neurological and metabolic changes that may elicit a long list of symptoms, including but not limited to headaches, dizziness, confusion, and balance disturbances. Physical abnormalities brought on by concussions do not show up on MRI or CT scans. Unfortunately, to date, no universally accepted or standardized diagnostic criteria for concussion exist.
Which is best, Play or Rest?
The original treatment modality for concussion involved both physical and cognitive rest, as developed by the International Concussion in Sport Group, which states, “The cornerstone of concussion management is physical and cognitive rest until the acute symptoms resolve and then a graded program of exertion prior to medical clearance and return to play.” The theories behind this decision do make sense. During the acute post-injury period (typically 1-7 days), the body experiences an increased metabolic demand coupled with limited quantities of adenosine triphosphate (ATP) reserves; given these dynamics, any additional or non-essential activity brings oxygen and glycogen away from the newly- injured neurons.
Cognitive impairment following concussion, a common occurrence among student athletes, suggests that cognitive rest may enhance recovery. The reasoning behind this theory rests on the presumption that increasing cognitive activity following SRC will increase symptom recovery time and prolong recovery. To that end, cognitive rest includes reducing brain -stimulating activities such as watching television, on-screen games, schoolwork, writing, and reading. Some studies have shown that returning to academic work while still experiencing symptoms may worsen one’s condition, resulting in a decline in academic performance.
This “period of dormancy” approach, however, may cause even more problems for athletes, including a hyperawareness of symptoms and social isolation. Decreasing school attendance can have a profoundly negative impact, going so far as to prevent student-athletes from learning about and putting into practice proper injury-coping mechanisms. Add to this the mental stigma of falling behind on assignments and academics, and one ends up creating an unnecessarily anxious learning environment, especially for those who already place a high value on excelling academically.
Some physicians have recently recommended that athletes consider engaging in limited physical and cognitive activity, provided it does not worsen symptoms. Fortunately, 80-90% of concussed individuals will return to pre-injury levels of functioning within two weeks, even in the absence of any intervention; however, a small percentage will continue to present with symptoms even up to 45 days post-injury, despite having successfully addressed other neurocognitive/balance issues.
Getting Proactive About Prevention Awareness
When it comes to concussions and traumatic brain injury, prevention remains the best point of intervention. Once these incidents occur, it very often proves difficult to repair and/or reverse any brain damage incurred, nor to address one’s increased susceptibility to secondary injuries. Raising awareness is key to prevention and can save lives. By its very nature, participation in contact sports cannot remove all risks, but concussion-prevention strategies can reduce the number and severity of concussions in many sports.
Effective injury prevention programs have the potential to reduce the risk of SRCs by as much as 34%, but overall, long-term data remains inconclusive. Still, more and more facilities, teams, and coaches have begun implementing a variety of programs aimed at different aspects of injury prevention. Below we list some of the protocols under consideration by teams and sports organizations:
- Rule Changes: Reducing collisions and high-risk actions can decrease the incidence of concussions. One research review found that eliminating body checking in youth hockey led to a 58% reduction in concussion rates. Similarly, limiting the amount of full-contact practice in American football may result in a 64% reduction in concussion occurrences.
- Protective Equipment: Use of mouthguards among hockey players of all ages led to a 28% reduction in concussion rates.
- Neuromuscular Training (NMT): Warm-up programs that focus on neuromuscular control have been shown to lower concussion rates and reduce musculoskeletal injuries. Such training typically includes 20 minutes of integrated balance, resistance, and plyometric training with sport-specific maneuvers as well as verbal feedback/reinforcement from coaches. Rugby players who underwent the NMT training protocols 3x/week had 59% fewer concussions compared to the control group.
- Optimal Management Strategies and Education: Strategies such as mandatory removal of athletes from play following concussions, concussion clearance protocols, and awareness campaigns focused on educating coaches/parents/athletes aligned with a 63% reduction in rates of recurrent concussions.
While emergency and sports medicine physicians remain focused on the treatment and management of concussions after the initial injury, coaches who offer education on/reinforcing of the aforementioned strategies can help prevent future concussions for young athletes.
Identifying Risk Factors
Experts who study concussion injuries and their ensuing complications have come up with 2 distinct risk factors: intrinsic and extrinsic. Knowing how to recognize each of these can help coaches and personal trainers develop effective, athlete-centered prevention protocols.
Intrinsic risk factors focus on the individual and are commonly classified as modifiable (e.g., neuromuscular or sensorimotor control) or non-modifiable (e.g., taking into account the individual’s previous history of concussion, sex, age, and genetics). Research remains inconsistent with regard to gender as a risk factor for concussion; however, it seems that in some sports, females fall into a higher risk category than males playing the same sport. The risk may differ due to physical characteristics or because women seem more inclined to report symptoms. We will discuss gender-specific details later in the article.
Extrinsic factors, or those associated with the environment or the sport itself, can often be easily modified to lessen the risk of concussion occurrence. Contact and/or collision sports, such as rugby, American football, and hockey, have the highest reported incidence of concussion. In youth ice hockey leagues where bodychecking is permitted, athletes report a 4-fold increase in concussion risk in the 11- to 12-year age group. Changes to the rulebook could go a long way towards injury prevention.
Continuum of Prevention
In order to remain as highly effective as possible, experts have broken down the concept of prevention into 3 strategic steps:
- Primary prevention
- Secondary prevention
- Tertiary prevention
We will address each of these individually and come to understand how they work together to protect athletes from SRCs.
Primary prevention interventions, designed and proven to be highly effective at reducing concussion risk, incorporate more than just protective gear and proper sports-specific technique. They target athletes who participate in sports that pose the highest SRC risks: football, hockey, soccer, and rugby.
A primary level of prevention should incorporate the following protocols and recommendations:
- Increasing awareness of SRC risks.
- Educating athletes on the causes, signs, and symptoms of concussions, safe concussion management and how to best protect themselves from injury.
- Education should target a broad range of individuals ~ athletes, parents, coaches, school administrators, athletic directors, teachers, athletic trainers, physicians and any other health care providers.
- Coaching safe, sports-specific skills and banning/limiting use of certain drills/techniques.
- Ensure that equipment meets national guidelines and gets properly worn for the specific purpose, including helmets in good condition that fit well.
- Educate players about the correct way to prevent blows to the helmet.
- Promoting fair play policies/safest rules.
- Improve and practice safe and effective tackling techniques. Proper technique takes time to perfect; regular practicing should begin with the youngest athletes in order to make it instinctive.
Secondary prevention strategies serve equally important roles to avoid further concussions during a play where an athlete has already suffered a concussive head injury. It targets early diagnosis/ prevention of concussion recurrence through a pre-injury assessment. Athletes diagnosed as concussed often have mild or variable symptoms, which physicians find difficult to pinpoint/ define. Therefore, experts suggest that coaches have objective pre-injury data to use as a point of comparison. To that end, pre-season baseline tests can help identify subtle impairment and may help a clinician make individualized return-to-play decisions (by comparing with pre-injury results).
From a secondary prevention perspective, the implementation of concussion management protocols incorporates steps to reduce the risk of early recurrence of concussion after allowing athletes to resume higher-risk activities. Consider the following:
- Promoting how to recognize suspected concussions/signs and symptoms.
- Responding quickly and appropriately to suspected incidents, including removing the athlete from play, never returning to play the same day, and returning to play only after being evaluated by a specially-trained health care provider.
- Following recommendations for physical/ cognitive/emotional rest protocols to allow for a gradual return to play.
Tertiary prevention focuses on rehabilitation strategies to prevent longer-term consequences of concussion. While primary prevention in youth sports aims to decrease the incidence of concussion, the secondary and tertiary intervention strategies include a variety of targets for reducing the risk and ensuing consequences of concussion injury.
Physical Therapy
Coaches and trainers also embrace the effectiveness of physical therapy interventions for adolescent/young adult athletes following a concussion. Embarking upon physical activity and physical therapy as early as a couple of days following injury proves beneficial at decreasing post-concussion symptoms, allows for shorter recovery time/earlier return to play, and is generally considered completely safe when executed under the supervision of a trained physical therapist.
Along with other multi-modal approaches, neck strengthening has emerged as a fairly new frontier in combatting sports-related concussions. This area of research emphasizes the cervical musculature’s ability to reduce head impacts and protect the player from neck injury. While many risk factors cannot be completely eliminated or even altered, a number of studies examining the correlation between neck strength and concussion risk have found that proper physical therapy can, in fact, enhance neck strength.
Scientists hypothesize that concussions most often occur through linear and rotational head accelerations, such as in the case of whiplash. Here, they find that strengthening the neck can prove advantageous in helping prevent concussions. Skeletal muscles not only produce force but also should absorb shock (decelerate) movements. Thus, athletes with stronger neck muscles could potentially better control the whiplash-type movement that occurs when the body is slammed during high-impact sports, reducing the likelihood of a concussion.
Another critical piece of the concussion prevention strategy involves training the cervical spine so it can safely absorb the impacts that commonly occur in contact sports. Physical therapists accomplish this by focusing on the ligaments/connective tissue of the spine; a strong spine and core remain the cornerstones of one’s overall strength. After release from therapy, personal trainers can capitalize on this foundation by choosing exercises designed to enhance reaction speed to sudden impulsive loads. Research shows a strong association between whiplash-induced injuries and concussion; therefore, the theory states that if the whiplash effect gets diminished by increasing neck/core strength, it can also likely reduce the risk of concussion.
Eye-Tracking Skills as a Preventative Measure
Vision therapy, also known as oculomotor therapy, can serve as yet another viable way to help prevent concussions. According to one research study, accurate vision enables football players to use their eyes and brains to process information in their periphery, allowing them to react faster to their environment and, ideally, avoid injury-causing collisions. Such therapy includes functional skills such as eye-tracking, focusing, eye teaming (the way the eyes work together), and hand-eye coordination.
Neuromuscular Training
Once an athlete receives medical clearance and resumes sports participation, undergoing some neuromuscular training can foster safer and more positive adaptations to thwart future concussions.
One research study sought to determine the feasibility of an 8-week-long neuromuscular training program initiated upon return-to-play clearance following concussion. Twenty-seven subjects participated and were randomly assigned to receive either standard post-concussion exercises or neuromuscular training.
Participants completed three assessments: within 14 days post-concussion, immediately after return-to-play clearance, and 8 weeks following return-to-play clearance. The intervention aimed to achieve positive neuromuscular adaptations and occurred 2x/week for 8 weeks under supervision. Those who received specialized training protocols did, in fact, cultivate better adaptation mechanisms.
Some medical professionals believe that neuromuscular adaptive training could potentially mitigate the increased risk of musculoskeletal (MSK) injuries often observed in concussion patients returning to sports.
One hypothesis suggests that despite clinical recovery, athletes cleared to return to play following concussion may harbor residual neuromuscular and/or attentional impairments that often go undetected via traditional concussion tests. This renders them vulnerable to further injury. Dual-task gait (simultaneous motor and cognitive task execution) looks specifically at neuromuscular control and attention and can identify otherwise unnoticed post-concussion impairments.
The Risk to Young Female Athletes
According to national data, approximately 1 in every 4 individuals reports suffering at least 1 concussion by the time they reach adolescence. Young female athletes in particular seem more prone to suffering SRCs. They also experience more severe symptoms and require a longer recovery period. Sadly, the majority of research studies on concussions (upwards of 80%) only recruited male subjects.
One study, funded by the NIH’s Building Interdisciplinary Research Careers in Women’s Health Program, took place under the guidance of Dr. Jessie Oldham, assistant professor at the VCU School of Medicine’s Department of Physical Medicine and Rehabilitation. She feels that “the ultimate goal is to develop individualized treatments for athletes that account for inherent demographic characteristics, like sex, age, and concussion history.”
Oldham believes that concussions may elevate the risk of future injury by interfering with the body’s startle reflex – a defensive response against sudden threats or events. In a study recently published in the Journal of Head Trauma and Rehabilitation, Dr. Oldham found that traumatic brain injuries such as concussions can suppress a person’s ability to react to unexpected stimuli.
“When you think about an athlete engaging in a sport, they’re having to respond quickly to a constantly changing environment, whether that’s keeping track of a ball or avoiding collisions with another player,” Oldham said. “My overarching hypothesis is that if athletes with a history of concussions are not able to respond to these kinds of stimuli as they normally would, they are potentially more likely to get hurt.”
As part of this study, research participants undergo a series of assessments to better understand how concussions have influenced their acoustic startle reflex, visual function, and reaction time. For one of the exercises, the research team tests a participant’s startle response by measuring muscle activity around the eyes during blinks following an unexpected noise. They also take part in a reaction-time test, in which they try to tap their finger to a dot on a screen as soon as it changes color.
In addition to reflex assessments, the researchers speak with the subjects about their psychological readiness to return to sports. They try to understand the level of stress brought on by the concussion, how confident they feel about returning to sports, and their fear of getting reinjured. Female athletes in general tend to report more symptoms, such as anxiety levels and depression, as compared to their male counterparts.
Long-Term Considerations
Research into the long-term effects of concussions remains limited. Despite increasing concerns that repetitive head trauma and SRCs may cause long-term cognitive impairment, current data remains insufficient to either suggest and/or confirm a causal relationship. Future studies may help identify the long-term impacts of concussions and repetitive head trauma in athletes, particularly those that occur during adolescence and young adulthood.
References
pmc.ncbi.nlm.nih.gov/articles/PMC4387881/
researchgate.net/profile/Alain-Ptito/publication/8208686_Current_Concepts_in_Concussion_Rehabilitation/links/09e4150642fdf43a32000000/Current-Concepts-in-Concussion-Rehabilitation.pdf
tbi-innovations.com/resources/161223-%7C-Schneider-Myer-helmet-no-brain-protect-BJSM-16l.pdf
pmc.ncbi.nlm.nih.gov/articles/PMC12638499/
emra.org/emresident/article/concussion-guideline-review
ijspt.scholasticahq.com/article/68071-the-effectiveness-of-physical-therapy-interventions-for-athletes-post-concussion-a-systematic-review
physio-pedia.com/Concussion_Prevention_Strategies
link.springer.com/rwe/10.1007/978-3-031-58351-3_489
sciencedirect.com/science/article/abs/pii/S1466853X21001413
pmc.ncbi.nlm.nih.gov/articles/PMC6222152/
vcuhealth.org/news/head-in-the-game-vcu-led-study-looks-to-advance-concussion-care-for-female-athletes/
