Therapeutic Effect of Aerobic Exercise for Adolescents After Mild Traumatic Brain Injury and Sport-Related Concussion: A Meta-Analysis from Randomized Controlled Trials

Optimal Volume of Moderate-to-Vigorous Physical Activity Postconcussion in Children and Adolescents

Importance

Determining the optimal volume of early moderate-to-vigorous-intensity physical activity (MVPA) after concussion and its association with subsequent symptom burden is important for early postinjury management recommendations.

Objectives

To investigate the association between cumulative MVPA (cMVPA) over 2 weeks and subsequent symptom burden at 1 week, 2 weeks, and 4 weeks postinjury in children and examine the association between cMVPA and odds of persisting symptoms after concussion (PSAC) at 2 weeks and 4 weeks postinjury.

Design, Setting, and Participants

This multicenter cohort study used data from a randomized clinical trial that was conducted from March 2017 to December 2019 at 3 Canadian pediatric emergency departments in participants aged 10.00 to 17.99 years with acute concussion of less than 48 hours. Data were analyzed from July 2022 to December 2023.

Exposure

cMVPA postinjury was measured with accelerometers worn on the waist for 24 hours per day for 13 days postinjury, with measurements deemed valid if participants had 4 or more days of accelerometer data and 3 or fewer consecutive days of missing data. cMVPA at 1 week and 2 weeks postinjury was defined as cMVPA for 7 days and 13 days postinjury, respectively. Multiple imputations were carried out on missing MVPA days.

Main Outcomes and measures

Self-reported postconcussion symptom burden at 1 week, 2 weeks, and 4 weeks postinjury using the Health and Behavior Inventory (HBI). PSAC was defined as reliable change on the HBI. A linear mixed-effect model was used for symptom burden at 1 week, 2 weeks, and 4 weeks postinjury with a time × cMVPA interaction. Logistic regressions assessed the association between cMVPA and PSAC. All models were adjusted for prognostically important variables.

Results

In this study, 267 of 456 children (119 [44.6%] female; median [IQR] age, 12.9 [11.5 to 14.4] years) were included in the analysis. Participants with greater cMVPA had significantly lower HBI scores at 1 week (75th percentile [258.5 minutes] vs 25th percentile [90.0 minutes]; difference, -5.45 [95% CI, -7.67 to -3.24]) and 2 weeks postinjury (75th percentile [565.0 minutes] vs 25th percentile [237.0 minutes]; difference, -2.85 [95% CI, -4.74 to -0.97]) but not at 4 weeks postinjury (75th percentile [565.0 minutes] vs 25th percentile [237.0 minutes]; difference, -1.24 [95% CI, -3.13 to 0.64]) (P = .20). Symptom burden was not lower beyond the 75th percentile for cMVPA at 1 week or 2 weeks postinjury (1 week, 259 minutes; 2 weeks, 565 minutes) of cMVPA. The odds ratio for the association between 75th and 25th percentile of cMVPA and PSAC was 0.48 (95% CI, 0.24 to 0.94) at 2 weeks.

Conclusions and Relevance

In children and adolescents with acute concussion, 259 minutes of cMVPA during the first week postinjury and 565 minutes of cMVPA during the second week postinjury were associated with lower symptom burden at 1 week and 2 weeks postinjury. At 2 weeks postinjury, higher cMVPA volume was associated with 48% reduced odds of PSAC compared with lower cMVPA volume.

The Effects of Rest on Concussion Symptom Resolution and Recovery Time: A Meta-analytic Review and Subgroup Analysis of 4329 Patients

BACKGROUND

Numerous individual studies suggest that rest may have a negative effect on outcomes following concussion.

PURPOSE

To perform a systematic meta-analysis of the effects of prescribed rest compared with active interventions after concussion.

STUDY DESIGN

Meta-analysis; Level of evidence, 4.

METHODS

A meta-analysis (using the Hedges g) of randomized controlled trials and cohort studies was conducted to evaluate the effects of prescribed rest on symptoms and recovery time after concussion. Subgroup analyses were performed for methodological, study, and sample characteristics. Data sources were obtained from systematic search of key terms using Ovid Medline, Embase, Cochrane Database of Systematic Reviews, APA PsycINFO, Web of Science, SPORTDiscus, and ProQuest dissertations and theses through May 28, 2021. Eligible studies were those that (1) assessed concussion or mild traumatic brain injury; (2) included symptoms or days to recovery for ≥2 time points; (3) included 2 groups with 1 group assigned to rest; and (4) were written in the English language.

RESULTS

In total, 19 studies involving 4239 participants met criteria. Prescribed rest had a significant negative effect on symptoms (k = 15; g = -0.27; SE = 0.11; 95% CI, -0.48 to -0.05; P = .04) but not on recovery time (k = 8; g = -0.16; SE = 0.21; 95% CI, -0.57 to 0.26; P = .03). Subgroup analyses suggested that studies with shorter duration (<28 days) (g = -0.46; k = 5), studies involving youth (g = -0.33; k = 12), and studies focused on sport-related concussion (g = -0.38; k = 8) reported higher effect sizes.

CONCLUSION

The findings support a small negative effect for prescribed rest on symptoms after concussion. Younger age and sport-related mechanisms of injury were associated with a greater negative effect size. However, the lack of support for an effect for recovery time and the relatively small overall numbers of eligible studies highlight ongoing concerns regarding the quantity and rigor of clinical trials in concussion.

REGISTRATION

CRD42021253060 (PROSPERO).

Relation of Aerobic Activity to Cognition and Well-being in Chronic Mild Traumatic Brain Injury: A LIMBIC-CENC Study

INTRODUCTION

Because chronic difficulties with cognition and well-being are common after mild traumatic brain injury (mTBI) and aerobic physical activity and exercise (PAE) is a potential treatment and mitigation strategy, we sought to determine their relationship in a large sample with remote mTBI.

MATERIALS AND METHODS

The Long-Term Impact of Military-Relevant Brain Injury Consortium-Chronic Effects of Neurotrauma Consortium prospective longitudinal study is a national multicenter observational study of combat-exposed service members and veterans. Study participants with positive mTBI histories (n = 1,087) were classified as "inactive" (23%), "insufficiently active" (46%), "active" (19%), or "highly active" (13%) based on the aerobic PAE level. The design was a cross-sectional analysis with multivariable regression. PAE was reported on the Behavioral Risk Factor Surveillance System. Preselected primary outcomes were seven well-validated cognitive performance tests of executive function, learning, and memory: The California Verbal Learning Test-Second Edition Long-Delay Free Recall and Total Recall, Brief Visuospatial Memory Test-Revised Total Recall, Trail-Making Test-Part B, and NIH Toolbox for the Assessment of Neurological Behavior and Function Cognition Battery Picture Sequence Memory, Flanker, and Dimensional Change Card Sort tests. Preselected secondary outcomes were standardized self-report questionnaires of cognitive functioning, life satisfaction, and well-being.

RESULTS

Across the aerobic activity groups, cognitive performance tests were not significantly different. Life satisfaction and overall health status scores were higher for those engaging in regular aerobic activity. Exploratory analyses also showed better working memory and verbal fluency with higher aerobic activity levels.

CONCLUSIONS

An association between the aerobic activity level and the preselected primary cognitive performance outcome was not demonstrated using this study sample and methods. However, higher aerobic activity levels were associated with better subjective well-being. This supports a clinical recommendation for regular aerobic exercise among persons with chronic or remote mTBI. Future longitudinal analyses of the exercise-cognition relationship in chronic mTBI populations are recommended.

Efficacy of aerobic exercise following concussion: a narrative review

Concussion is a type of mild traumatic brain injury which results in symptoms within the physical, cognitive, emotional, and sleep domains. Historically, guidelines established by expert opinion have recommended rest during the initial stages of recovery following a concussion until symptom resolution. However, recent recommendations have shifted to advise an initial period of 24-48 h of rest immediately following concussion with the gradual introduction of light-to-moderate intensity aerobic exercise thereafter. Given the relatively recent transition in recommendations, the aim of this review is to provide an overview of the current literature on the efficacy of aerobic exercise following concussion. The current literature is limited to studies assessing the impact of standardized aerobic exercise following concussion. Upon review, literature suggests participating in aerobic exercise below the point of symptom exacerbation is safe in both the acute and chronic post-concussion symptom stages of recovery and does not delay time to medical clearance. Future large-scale randomized controlled trials assessing the impact of aerobic exercise and differences between males and females would help support the current evidence suggesting aerobic exercise could improve time to recovery following concussion and identify any sex differences in response. As well, future studies with the purpose of identifying optimal aerobic exercise volume and intensity in the treatment of concussion could improve the specificity of the current guidelines.