Exertional Tolerance Assessments After Mild Traumatic Brain Injury: A Systematic Review

Abstract

Objective The objective of this study was to review the literature to identify and summarize strategies for evaluating responses to physical exertion after mild traumatic brain injury (mTBI) for clinical and research purposes. Data sources PubMed and EBSCOHost through December 31, 2016. Study Selection Two independent reviewers selected studies based on the following criteria: 1) inclusion of participants with mTBI/concussion, 2) use of a measurement of physiological or psychosomatic response to exertion, 3) a repeatable description of the exertion protocol was provided, 4) a sample of at least 10 participants with a mean age between 8–65 years, and 5) the article was in English. The search process yielded 2,685 articles, of which 14 studies met the eligibility requirements. Data Extraction A quality assessment using a checklist was conducted for each study by two independent study team members and verified by a third team member. Data were extracted by a one team member and verified by a second team member. Data Synthesis A qualitative synthesis of the studies revealed that most protocols employed a treadmill or cycle ergometer as the exercise modality. Protocol methods varied across studies including differences in initial intensity determination, progression parameters, and exertion duration. Common outcome measures were self-reported symptoms, heart rate, and blood pressure. Summary/conclusions The strongest evidence indicates that exertional assessments can provide important insight about mTBI recovery and should be administered using symptoms as a guide. Additional studies are needed to verify an optimal modes and protocols for post-mTBI exertional assessments.

A pilot study on exertional tasks with physiological measures designed for the assessment of military concussion

“…The implementation of standardized exertional tasks that includes an objective physiological measure may improve the standard of care for military mTBI. Monitoring symptoms, RPE, and HR during exertional tasks assesses physiological recovery and informs activity recommendations [35]. The treatment and management of concussion remains a priority for TBI CoE and the armed forces.…”

“…Participants completed a demographic questionnaire including questions on self-reported concussion history, military experience, current pain (0-10 scale), sleep (number of hours) and caffeine (number of drinks) within the past 24 h. Rate of perceived exertion (RPE) using the Borg Scale, a 6-20 scale reflecting subjective measure of workload, was used to document self-perceived exertion during exercise [35]. The presence or increase of symptoms was assessed using a 0-10 Likert scale focusing on headache, dizziness, nausea, light/sound sensitivity and fogginess, similar to the approach used in other exertional tests for concussion [23,36].…”

Active recovery from concussion

“…(29) A recent systematic review found that the strongest evidence indicates that exertional assessments can provide important insight about mild traumatic brain injury (TBI) recovery and should be administered using symptoms as a guide. (30) Others are even beginning to use graded aerobic treadmill testing to safely assess exercise tolerance in patients with more moderate to severe head trauma. (31) Thus the emerging evidence suggests that symptomlimited assessment of exercise tolerance can safely be used by clinicians to evaluate patients with PCS, as well as in adolescents within the first week after SRC, and potentially provide a physiological indicator of concussion severity beyond the level of initial symptom burden.…”

The Effects of Including Aerobic Exercise in the Treatment Protocol of Concussions: A Systemic Review and Meta-analysis

“…Despite the growing body of literature surrounding exercise as treatment for concussions, there are no universally-established guidelines for prescribing exercise and aerobic exercise intensities for concussed individuals (Buckley et al, 2017;Quatman-Yates et al, 2017). It is believed that aerobic exercise helps improve cognitive function and memory through the release of BDNF (Maass et al, 2016).…”

“…The review pointed out that there is evidence in animal models that aerobic exercise does up-regulate neuroplasticity in rodents suffering from a simulated concussion or brain injury, and that there is enough evidence to support the conclusion that aerobic exercise could be used as a treatment for concussion symptoms (Leddy et al, 2018). However, standardized methods for identifying an appropriate exercise intensity in a concussion treatment protocol do not exist (Buckley et al, 2017;Quatman-Yates et al, 2017). A treadmill protocol for an exercise test to determine a sub-symptom threshold for exercise in concussed individuals does exists, but the concussed individual must have access to a treadmill and a medical professional trained in executing and evaluating the test (Leddy & Willer, 2013).…”