Moderate Exercise Benefits Post-Concussive Symptoms & Cognitive Function in Youth

by Ashley Jordan Ferira, PhD, RDN

Mild traumatic brain injury (TBI), AKA “concussion,” results from an impact to the head (e.g. bump, blow, jolt) that disrupts normal brain function or consciousness.¹ Concussions in youth are more common than you may think. In 2016, 19.5% of US adolescents reported at least 1 diagnosed concussion during their lifetime, with 5.5% reporting >1 concussion.² In addition to competitive sports participation (particularly contact sports), other characteristics associated with a higher concussion rates include being male, white, and in a higher grade in school.² In 2012 alone, over 300,000 US children (≤19 years) were treated in the ER for sports and recreation-related injuries that included a concussion or TBI diagnosis.³

Although not yet proven, researchers posit that the neuroplasticity of the developing brain may make the pediatric population more vulnerable to concussive injury. A delicate balance is thought to exist between concussion recovery and return to physical activity; extended rest/inactivity and premature return to activities may both potentially increase risk for prolonged or exacerbated post-concussive symptoms (PCS), but pediatric concussion literature is limited.⁴

A recent experimental case-control study examined the effect of strenuous exercise on PCS and neurocognitive efficiency in Australian children and adolescents.⁴ The study included 60 youth (41 males; 19 females) aged 10-18 years divided into 2 groups: diagnosed concussion (n=30) and healthy controls (n=30).⁴ Controls were matched to the concussed children based on age, developmental and medical history, and level of physical activity participation. Exclusion criteria included (but not limited to) patients experiencing multiple traumas, requiring intubation and/or neurosurgical intervention, or with clinical evidence of cerebrospinal fluid leak or intracranial injury.⁴

At days 2 and 10 following PCS resolution (self-report), participants completed the exercise protocol: McMaster All-Out Progressive Continuous Cycling Test, which involves 8 minutes of sub-maximal exercise on a stationary exercise bike, with resistance level increased based on the participant’s height.^4-5 Measurements of PCS and cognitive efficiency were assessed pre- and post-exercise. Compared to controls, recently concussed patients demonstrated:⁴

• ↓ in 5 symptom clusters of PCS (arousal, somatic, cognitive, emotional, sleep) measured via CogSport Symptom Scale
• ↑ reaction times on computerized cognitive tasks (CogSport tool) assessing information processing and new learning

The study investigators hypothesized that the exercise intervention would increase PCS and decrease cognitive functioning in the concussed children, but their controlled study results failed to support this theory.⁴ In fact, the exercise intervention revealed therapeutic benefits to the concussed children.⁴ Interestingly, the study participants perceived/rated the exercise routine as “moderate” intensity, perhaps reflecting a high baseline fitness level. To that end, it may be most accurate to conclude that this study supports the implementation of moderate exercise for the management of concussion following acute symptom resolution.⁴ Additional studies evaluating the impact of exercise in pediatric and adult concussed patients with diverse baseline fitness levels and demographics will be valuable.

Why is this Clinically Relevant?

• Pediatric concussion is relatively common,^1-3 and targeted, evidence-based lifestyle interventions are needed to support recovery
• Following acute PCS resolution, moderate exercise may be considered for the reduction of concussion symptoms⁴

View the abstract

 Citations

1. CDC. TBI: Get the Facts. https://www.cdc.gov/traumaticbraininjury/get_the_facts.html. Accessed August 16, 2018.
2. Veliz P, McCabe SE, Eckner JT, Schulenberg JE. Prevalence of concussion among US adolescents and correlated factors. JAMA. 2017;318(12):1180-1182.
3. Coronado VG, Haileyesus T, Cheng TA, et al. Trends in sports- and recreation-related traumatic brain injuries treated in US emergency departments: The National Electronic Injury Surveillance System-All Injury Program (NEISS-AIP) 2001-2012. J Head Trauma Rehabil. 2015;30(3):185–197.
4. Anderson V, Manikas V, Babl FE, Hearps S, Dooley J. Impact of moderate exercise on post-concussive symptoms and cognitive function after concussion in children and adolescents compared to healthy controls. Int J Sports Med. 2018;39:696-703.
5. Bar-Or O. Pediatric Sports Medicine for the Practitioner. From Physiological Principles to Clinical Applications. New York: Springer Verlag: 1983.