A Preliminary Investigation of Accelerometer-Derived Sleep and Physical Activity Following Sport-Related Concussion

Scoping review: Intervention for ocular motor disorders in children and adults with mild traumatic brain injury

SIGNIFICANCE

Intervention strategies for post-mild traumatic brain injury (mTBI) ocular motor disorders vary across disciplines and include watchful waiting, vestibular rehabilitation, vision rehabilitation/vision therapy, and optical intervention. However, evidence supporting their effectiveness is limited, highlighting the need for high-quality randomized controlled trials with standardized testing, diagnostic criteria, and reassessment of ocular motor function after intervention.

BACKGROUND

Ocular motor disorders occur frequently after mTBI.

OBJECTIVES

This study aimed to conduct a scoping review of interventions for mTBI-related ocular motor disorders in children and adults.

DATA SOURCES

The following electronic bibliographic databases were searched: PubMed, Embase, PEDro, OVID, Clinical Key, Google Scholar, and REHABDATA.

STUDY SELECTION

Intervention studies published in English between 2003 and 2024 involving mTBI participants who had an ocular motor assessment prior to intervention were included in this study.

DATA EXTRACTION AND SYNTHESIS

Preferred Reporting Items for Systematic reviews and Meta-Analyses extension for Scoping Reviews guidelines were followed for reporting. Study population, intervention, and outcomes were extracted and synthesized in tabular and graphical formats.

RESULTS

Sixty-seven eligible studies were included, with only three (4%) judged as low risk of bias. Intervention strategies included watchful waiting (n = 31, 46%), vestibular rehabilitation (n = 13, 19%), vision rehabilitation/vision therapy (n = 10, 15%), optical intervention (n = 4, 6%), and alternative interventions or multifaceted interventions (n = 9, 14%). Among the studies providing statistically supported results, improvements in one or more ocular motor outcome domains were reported in nearly 80% of the studies on watchful waiting (19/24) and 100% of the studies on vestibular rehabilitation (4/4), vision rehabilitation/vision therapy (7/7), or optical intervention (1/1).

CONCLUSIONS AND IMPLICATIONS

Although post-mTBI ocular motor deficits improved with watchful waiting strategy, vestibular rehabilitation, vision rehabilitation/vision therapy, and optical interventions, most studies had significant risk of bias. This review emphasizes the necessity for high-quality randomized controlled trials with standardized testing protocols and diagnostic criteria and reassessment of ocular motor functions after intervention to evaluate the effectiveness of these interventions in different age groups and recovery stages.

Clinical Measures Associated with Subsequent Injury after Adolescent Concussion: A Prospective Cohort Study

PURPOSE

This study aimed to examine associations between clinical measures (self-reported and clinician administered) and subsequent injury rates in the year after concussion return to play (RTP) among adolescent athletes.

METHODS

We performed a prospective, longitudinal study of adolescents ages 13-18 yr. Each participant was initially assessed within 21 d of concussion and again within 5 d of receiving RTP clearance from their physician. Participants completed self-report measures: the Pittsburgh Sleep Quality Index and Tampa Scale of Kinesiophobia, and clinician-administered measures: single- and dual-task tandem gait and reaction time (RT; simple and clinical) assessments. They then completed monthly surveys for a year after RTP, which assessed exposure to injury (sport participation) and subsequent injuries (musculoskeletal or concussions) sustained. We used Poisson regression models to calculate injury rate ratios with the number of subsequent injuries sustained as the outcome, adjusted for RTP clearance time and competitive exposures for each measure.

RESULTS

Forty-one participants were included (age = 15.5 ± 1.3 yr, 56% female, 9.6 ± 4.6 d postconcussion; 38.0 ± 31.5 d to RTP). A higher injury rate per athletic exposure was observed for simple RT ≥ 505 ms versus <505 ms (injury rate ratio = 2.96, 95% confidence interval = 1.41-6.60, P = 0.005). Injury rates did not significantly differ by Pittsburgh Sleep Quality Index or Tampa Scale of Kinesiophobia scores, single/dual-task tandem gait time, or clinical RT.

CONCLUSIONS

Simple RT may be one risk factor that is associated with higher rates of subsequent injury after adolescent concussion. A simple RT measure incorporated into a comprehensive concussion RTP assessment may identify some individuals at higher risk of subsequent injury in the year after concussion, although further research is needed to better understand this relationship.

Prospective evaluation of 24-hour movement behaviors among adolescents recovering from a sport-related concussion

This study aimed to describe the 24-hour composition of movement behaviors, including sleep, sedentary behavior, and physical activity (PA), among pediatric sports-related concussion (SRC) patients over their recovery period, assess the association between movement compositions and recovery time, and understand feasibility of 24-hour accelerometry in the study population. A cohort of 50 pediatric SRC patients were asked to wear a wrist-worn accelerometer continuously for the duration of their recovery. Among all enrolled participants, the sample was primarily 14 or 15 years of age (65%), female (55%), and recovered in under 28 days (88%). Accelerometer compliance was moderate; 35 participants (70%) were compliant with the protocol. Compositional analysis was used to address time-use objectives in 33 participants who provided adequate data for inclusion. Overall, participants spent an average of 50% of their 24-hour day sedentary, 33% sleeping, 11% in light intensity PA, and 6% in moderate or vigorous intensity PA. The 24-hour composition of movement behaviors was not associated with recovery time (p = .09-.99). However, the limited sample size may have contributed to null findings. Given recent evidence supporting the effects of sedentary behavior and PA on concussion recovery, future studies should aim to further validate these findings in a larger sample.

Data Analytics in Physical Activity Studies With Accelerometers: Scoping Review

BACKGROUND

Monitoring free-living physical activity (PA) through wearable devices enables the real-time assessment of activity features associated with health outcomes and provision of treatment recommendations and adjustments. The conclusions of studies on PA and health depend crucially on reliable statistical analyses of digital data. Data analytics, however, are challenging due to the various metrics adopted for measuring PA, different aims of studies, and complex temporal variations within variables. The application, interpretation, and appropriateness of these analytical tools have yet to be summarized.

OBJECTIVE

This research aimed to review studies that used analytical methods for analyzing PA monitored by accelerometers. Specifically, this review addressed three questions: (1) What metrics are used to describe an individual's free-living daily PA? (2) What are the current analytical tools for analyzing PA data, particularly under the aims of classification, association with health outcomes, and prediction of health events? and (3) What challenges exist in the analyses, and what recommendations for future research are suggested regarding the use of statistical methods in various research tasks?

METHODS

This scoping review was conducted following an existing framework to map research studies by exploring the information about PA. Three databases, PubMed, IEEE Xplore, and the ACM Digital Library, were searched in February 2024 to identify related publications. Eligible articles were classification, association, or prediction studies involving human PA monitored through wearable accelerometers.

RESULTS

After screening 1312 articles, 428 (32.62%) eligible studies were identified and categorized into at least 1 of the following 3 thematic categories: classification (75/428, 17.5%), association (342/428, 79.9%), and prediction (32/428, 7.5%). Most articles (414/428, 96.7%) derived PA variables from 3D acceleration, rather than 1D acceleration. All eligible articles (428/428, 100%) considered PA metrics represented in the time domain, while a small fraction (16/428, 3.7%) also considered PA metrics in the frequency domain. The number of studies evaluating the influence of PA on health conditions has increased greatly. Among the studies in our review, regression-type models were the most prevalent (373/428, 87.1%). The machine learning approach for classification research is also gaining popularity (32/75, 43%). In addition to summary statistics of PA, several recent studies used tools to incorporate PA trajectories and account for temporal patterns, including longitudinal data analysis with repeated PA measurements and functional data analysis with PA as a continuum for time-varying association (68/428, 15.9%).

CONCLUSIONS

Summary metrics can quickly provide descriptions of the strength, frequency, and duration of individuals' overall PA. When the distribution and profile of PA need to be evaluated or detected, considering PA metrics as longitudinal or functional data can provide detailed information and improve the understanding of the role PA plays in health. Depending on the research goal, appropriate analytical tools can ensure the reliability of the scientific findings.

A controlled early-exercise rehabilitation program commencing within 48 hours of a Sports-Related Concussion improves recovery in UK student-athletes: A prospective cohort study

OBJECTIVES

Explore if implementing an individualised Sub-Symptom Heart Rate Threshold (SSHeRT) rehabilitation program within 48 hours versus physical rest for 14 days affects recovery following SRC in university-aged student-athletes.

DESIGN

Prospective, observational cohort study.

METHODS

Two UK university-aged student-athlete rugby union cohorts were compared (Physical Rest Group (PRG), n = 140, July 2019-March 2020 and Controlled Early-Exercise Group (CEG), n = 167, July 2021-April 2023). Both groups completed the test battery (Post-Concussion Symptom Scale (PCSS), Immediate Post-Concussion and Cognitive Test (ImPACT), Vestibular-Ocular Motor Screening Tool (VOMS)) during pre-season to provide a baseline and within 48 hours, at 4, 8, 14-days post-SRC and at Return to Play (RTP). The PRG (n = 42) physically rested for 14 days as per the nationwide community guidelines. The CEG (n = 52) followed the SSHeRT rehabilitation program. Individual change to baseline was used in all analyses.

RESULTS

The CEG performed better on ImPACT's verbal memory at 4 (PRG; -5.5 (-10.8-0.0), CEG; 1.0 (-2.0-10.5), p = 0.05) and 14 days (PRG; -2.0 (-10.0-3.0), CEG; 4.0 (-1.0-11.0), p = 0.05) and on the VOMS at 4 (PRG; 3.0 (0.0-12.0), CEG; 0.0 (0.0-5.0), p = 0.03, OR; 2.910) and 14-days post-SRC (PRG; 0.0 (0.0-1.0), CEG; 0.0 (0.0-0.0), OR; 5.914). Near point convergence was better at all time points for the CEG. The CEG was 26.7 % more likely to have RTP within 30 days, and 6.7 and 5.1 times more likely to have resumed non-contact and contact academic activities by 4 days.

CONCLUSIONS

SSHeRT is safe, can be used within 48 hours of a SRC and may hasten university-aged student-athletes recovery following an SRC.

Association between days for concussion recovery and initial specialty clinic evaluation within 48 hours

BACKGROUND

Researchers have highlighted the importance of early access to concussion care within one week of injury in reducing recovery times. However, a persisting question for concussion researchers is "just how early is important?" The purpose of this study was to examine differences in recovery time as predicted by the number of days elapsed since injury (DSI) to initial evaluation among patients who had access to a specialty concussion clinic within seven days. We hypothesized that DSI group membership, even within seven days, would significantly predict risk of protracted recovery (i.e., beyond 21 days).

METHODS

In this archival study, retrospective data were gathered from electronic medical records between September 2020 to March 2022. Records of participants between ages 12-18, those diagnosed with a sports-related concussion based on initial clinic visit diagnosis by a medical provider and those who established care within seven days of injury at a large pediatric specialty concussion clinic were examined. Participants were divided into three DSI groups (patients seen in < 48 h: "acute", patients seen between 49 h < and < 96 h: "sub-acute", and patients seen between 97 < and < 168 h: "post-acute"). A general linear model was constructed to examine relationships between relevant concussion factors (e.g., Post Concussion Scale Score, neurodevelopmental history, psychiatric history, concussion history, migraine history, overall VOMS change score, cognitive testing, sex, age, race, and ethnicity) that were either significant in the preliminary analysis or in clinical judgement and recovery time. Adjusted odds ratios (OR) were derived from a binary logistic regression model, in which recovery time was normal (≤ 21 recovery days) or protracted (> 21 recovery days).

RESULTS

A total of 856 participants were eligible. Adolescents in the acute group (M = 15.12, SD = 8.04) had shorter recovery times in days compared to those in the sub-acute (M = 17.98, SD = 10.18) and post-acute (M = 21.12, SD = 10.12; F = 26.00, p < .001) groups. Further, participants in the acute (OR = 4.16) and sub-acute (OR = 1.37) groups who accessed specialty concussion clinics within 48 h were 4 times more likely to have a normal recovery and recovered approximately 6 days faster than the post-acute care group.

CONCLUSIONS

Earlier concussion care access predicted recovery times and was associated with lower risk for protracted recovery.

Multidomain concussion symptoms in adolescents: A network analysis

Concussion is a heterogeneous injury involving symptoms and impairment that represent multiple domains (e.g., anxiety, cognitive, vestibular). Network analysis, a modeling technique that estimates relationships among symptoms, provides a statistically sound and clinically practical method for evaluating these interrelationships. The purpose of this study was to examine, using network analysis, relationships among clinical assessments and multidomain symptom report within a sample of adolescent patients following a concussion. Participants included 326 patients (49.7% female) aged 10-21 years presenting to a concussion specialty clinic within 28 days of a diagnosed concussion. Participants completed the Post-Concussion Symptom Scale (PCSS) and Vestibular-Ocular Motor Screening (VOMS) tool at initial visit. Network models were applied to PCSS symptoms initially, and then applied to VOMS and PCSS symptom data together. Dizziness (Expected influence (EI) = 1.10) and sadness (EI = 1.91) were most central (i.e., highest cumulative partial correlations) to the symptom network. Numerous interdomain relationships were supported, including irritability with mental fogginess (edgeweight = 0.12), dizziness with headache (edgeweight = 0.16), and dizziness with vision problems (edgeweight = 0.13). Community analyses resulted in VOMS groupings by domain (e.g., vestibular) and symptom (e.g., dizziness). The findings suggest a more direct focus on symptom interrelationships, such as how dizziness contributes to emotional symptoms, may help guide and better target treatments. Also, results suggest grouping VOMS assessment by symptom (e.g., dizziness) and item (e.g., vestibular-ocular reflex) may better reflect underlying impairments reflected by these symptom-item combinations.

Sleep/Wake Disorders After Sports Concussion: Risks, Revelations, and Interventions

SUMMARY

Sleep-wake disturbances (SWDs) are among the most prevalent, persistent, and often disregarded sequelae of traumatic brain injury. Identification and treatment of SWDs in patients with traumatic brain injury is important and can complement other efforts to promote maximum functional recovery. SWDs can accentuate other consequences of traumatic brain injury, negatively affect mood, exacerbate pain, heighten irritability, and diminish cognitive abilities and the potential for recovery. The risk for sports injuries increases when athletes are sleep deprived. Sleep deprivation increases risk-taking behaviors, predisposing to injuries. SWDs are an independent risk factor for prolonged recovery after sports-related concussion. SWDs following sports-related concussion have been shown to impede recovery, rehabilitation, and return to preinjury activities.

Sleep and Athletic Performance: Impacts on Physical Performance, Mental Performance, Injury Risk and Recovery, and Mental Health: An Update

Sleep health is an important consideration for athletic performance. Athletes are at high risk of insufficient sleep duration, poor sleep quality, daytime sleepiness and fatigue, suboptimal sleep schedules, irregular sleep schedules, and sleep and circadian disorders. These issues likely have an impact on athletic performance via several domains. Sleep loss and/or poor sleep quality can impair muscular strength, speed, and other aspects of physical performance. Sleep issues can also increase risk of concussions and other injuries and impair recovery after injury. Cognitive performance is also impacted in several domains, including vigilance, learning and memory, decision making, and creativity.

Physical Activity Following Sport-Related Concussion in Adolescents: A Systematic Review

OBJECTIVE

To evaluate the evidence related to how physical activity (PA) affects recovery following a sport-related concussion (SRC) in adolescents.

DESIGN

Systematic review Data Source: PUBMED, MEDLINE, and SPORTDiscus Eligibility criteria for selecting study:(1) original research article (e.g., randomized controlled trials (RCT), quasi-experimental designs, cohort, case-control studies), (2) 66% or greater of the sample has to have a SRC diagnosed by a clinician, (4) human research, (5) evaluate the effect of a SRC on PA in adolescents only (<18 years). Participants were seen within 1-2 weeks post-SRC for acute studies and 4 weeks post-SRC for studies focused on prolonged recoveries.

RESULTS

Twenty-two studies met the inclusion criteria (i.e., 8 regarding PA (PA-daily aerobic activity including light-moderate intensities), 8 evaluating active rehabilitation/exercise programs (20 minutes of daily aerobic exercise below symptom threshold), 6 examining a single bout of exertion). The methodological quality of the literature was assessed using the Downs and Black risk of bias (ROB) checklist. The ROB scores ranged from 7-24, with only two RCTs included. Studies demonstrated single bouts of exertion testing were safe and feasible. Daily PA or active rehabilitation/exercise programs led to a reduction in symptoms present and a decrease in number of days to medical clearance.

CONCLUSION

Following a brief period of rest (24-48 hours), individuals can gradually and safely return to PA below their physical symptom exacerbation thresholds. Further research is warranted to delineate how to optimize the timing, intensity, duration, and modality of PA impacts symptom resolution and physiological recovery following SRC.

Characterizing Sleep and Wakefulness in the Acute Phase of Concussion in the General Population: A Naturalistic Cohort from the Toronto Concussion Study

Growing literature links concussion to changes in sleep and wakefulness in humans and in rodent models. Sleep has been linked with synaptic reorganization under other conditions; however, the characterization and role of sleep after acute concussion remains poorly understood. While much research has focused on insomnia among patients with chronic or persistent concussion symptoms, there is limited understanding of sleep and acute concussion, its potential role in recovery, and associated risk factors for the development of chronic sleep disturbance. Studies to date are limited by small sample sizes of primarily athlete or military populations. Additional studies among the general population are critical to inform best practice guidelines. We examined the sleep and daytime wakefulness of 472 adults from a naturalistic general population cohort (mean age, 33.3 years, females = 60.8%) within seven days of diagnosed concussion, using a validated, condition-specific measure, the Sleep and Concussion Questionnaire. Participants identified immediate changes in sleep characterized by hypersomnia and difficulty maintaining daytime wakefulness; 35% considered these changes as moderate to severe and 79% required monitoring or follow-up. Females experienced significantly greater severity of changes in sleep compared with males. Positive correlations between severity of sleep and pain and headache were identified. Differences by sex are an important consideration for early intervention and long-term monitoring. Because sleep was compromised by pain, pain management is also an integral part of early intervention. Our findings suggest that assessment of sleep beginning in the acute stage is a critical component of concussion management in the general population.

Sleep Problems and Melatonin Prescription After Concussion Among Youth Athletes

OBJECTIVES

To examine the effect of sleep disturbances on concussion symptom recovery and to examine the effect of melatonin prescription on symptom improvement among concussed adolescents with sleep problems.

DESIGN

Longitudinal test-retest.

SETTING

Sports medicine clinic.

PARTICIPANTS

Patients aged 8 to 18 years, diagnosed with a concussion, evaluated within 14 days after injury, and evaluated again 15 to 35 days after injury.

INDEPENDENT VARIABLES

We grouped patients based on whether they reported sleep disturbances within 14 days of injury.

MAIN OUTCOME MEASURES

Outcome measures included symptom severity, headache severity, melatonin prescription, and the change in symptom severity between visits.

RESULTS

Two hundred twenty-five patients were included: 36% who reported sleep problems (44% female; age = 14.4 ± 2.0 years; evaluated 7.3 ± 3.8 and 23.2 ± 5.4 days after injury) and 64% who did not (32% female; age = 14.6 ± 2.3 years; evaluated 7.2 ± 3.4 and 23.0 ± 5.3 days after injury). Those with sleep problems reported higher symptom severity than those without across the 2 visits (22.1 ± 14.3 vs 14.6 ± 12.5; P < 0.001). There was no significant difference in the change in symptom severity between visits among those who received [median = 9-point improvement; interquartile range (IQR) = 1-14] and did not (median = 9, IQR = 2-18) receive a melatonin prescription (P = 0.80).

CONCLUSIONS

Sleep problems among pediatric patients within 2 weeks of concussion are associated with more severe symptoms. Melatonin prescription was not associated with faster symptom recovery.

Daily Morning Blue Light Therapy Improves Daytime Sleepiness, Sleep Quality, and Quality of Life Following a Mild Traumatic Brain Injury

OBJECTIVE

Identify the treatment effects of 6 weeks of daily 30-minute sessions of morning blue light therapy compared with placebo amber light therapy in the treatment of sleep disruption following mild traumatic brain injury.

DESIGN

Placebo-controlled randomized trial.

PARTICIPANTS

Adults aged 18 to 45 years with a mild traumatic brain injury within the past 18 months (n = 35).

MAIN OUTCOME MEASURES

Epworth Sleepiness Scale, Pittsburgh Sleep Quality Index, Beck Depression Inventory II, Rivermead Post-concussion Symptom Questionnaire, Functional Outcomes of Sleep Questionnaire, and actigraphy-derived sleep measures.

RESULTS

Following treatment, moderate to large improvements were observed with individuals in the blue light therapy group reporting lower Epworth Sleepiness Scale (Hedges' g = 0.882), Beck Depression Inventory II (g = 0.684), Rivermead Post-concussion Symptom Questionnaire chronic (g = 0.611), and somatic (g = 0.597) symptoms, and experiencing lower normalized wake after sleep onset (g = 0.667) than those in the amber light therapy group. In addition, individuals in the blue light therapy group experienced greater total sleep time (g = 0.529) and reported improved Functional Outcomes of Sleep Questionnaire scores (g = 0.929) than those in the amber light therapy group.

CONCLUSION

Daytime sleepiness, fatigue, and sleep disruption are common following a mild traumatic brain injury. These findings further substantiate blue light therapy as a promising nonpharmacological approach to improve these sleep-related complaints with the added benefit of improved postconcussion symptoms and depression severity.

RELATIONSHIP BETWEEN PHYSICAL ACTIVITY PARTICIPATION AND RECOVERY OUTCOMES IN COLLEGE-AGED ADULTS WITH A CONCUSSION

CONTEXT

Previously, the most common treatment for a concussion was prolonged physical and cognitive rest. Recent research suggests that earlier physical activity (PA) may be better at promoting recovery. Research has not evaluated the relationship between free-living PA (e.g., walking) and symptom reporting or recovery duration.

OBJECTIVE

To assess the relationship between free-living physical activity (PA) participation and two recovery outcomes in college-aged adults with a concussion.

DESIGN

Prospective Cohort Setting: Division 1 & 3 Universities Participants: Thirty-two college-aged adults (68.8% female, age: 19.8±1.4) with a concussion.

MAIN OUTCOME MEASURES

Participants completed a post-concussion symptom evaluation at visits 1 (<72 hours from concussion) and 2 (8 days later). Between visits, participants' PA was monitored using an Actigraph GT9X Link PA monitor and expressed as total PA (counts per minute) and percent time of PA spent in moderate-to-vigorous intensity (%MVPA). Recovery time was the number of days from injury occurrence to medical clearance. Separate hierarchical multiple regressions evaluated the relationship between total PA and each recovery variable (visit 2 symptom severity, recovery time). Additionally, separate exploratory hierarchical multiple regressions evaluated the relationship between %MVPA and each recovery variable. Statistical significance was set a priori at p ≤ .05.

RESULTS

Participants averaged 2446±441 counts per minute and spent 12.1±4.2% of their PA performing MVPA. Participants yielded median symptom severities of 28[24] and 2[8] for visit 1 and 2, respectively. Average recovery time was 14.7±7.5 days. Total PA did not significantly contribute to the model for visit 2 symptom severity (p=.122) or recovery time (p=.301). Similarly, %MVPA had little contribution to the model for visit 2 symptom severity (p=.358) or recovery time (p=.276).

CONCLUSION

Results suggest that free-living PA may not be enough to reduce symptoms or shorten recovery. Thus, clinicians may need to provide patients with more structured PA protocols mimicking previous research.

Sleep quality in the chronic stage of concussion is associated with poorer recovery: A systematic review

Background

Recovery from a concussion varies based on a multitude of factors. One such factor is sleep disturbances. In our prior review, it was observed that in the acute phase, sleep disturbances are predictive of poor outcomes following a concussion. The literature gap remains on how sleep in the chronic phase of recovery affects outcomes.

Objective

To examine the association between sleep quality during the chronic stage of concussion and post-concussion outcomes. Literature Survey: Literature searches were performed during 1 July to 1 August 2019 in selected databases along with searching grey literature. Out of the 733 results, 702 references were reviewed after duplicate removal.

Methods

Three reviewers independently reviewed and consented on abstracts meeting eligibility criteria ( n = 35). The full-text articles were assessed independently by two reviewers. Consensus was achieved, leaving four articles. Relevant data from each study was extracted using a standard data-extraction table. Quality appraisal was conducted to assess potential bias and the quality of articles.

Results

One study included children (18–60 months) and three studies included adolescents and/or adults (ranging 12–35 years). The association between sleep and cognition (two studies), physical activity (one study), and emotion symptoms (one study) was examined. Sleep quality was associated with decreased cognition and emotional symptoms, but not with meeting physical activity guidelines six months post-concussion injury.

Conclusions

The heterogeneity in age of participants and outcomes across studies and limited number of included studies made interpretations difficult. Future studies may consider if addressing sleep quality following concussion will improve outcomes.

Sleep and Athletic Performance: Impacts on Physical Performance, Mental Performance, Injury Risk and Recovery, and Mental Health

Research has characterized the sleep of elite athletes and attempted to identify factors associated with athletic performance, cognition, health, and mental well-being. Sleep is a fundamental component of performance optimization among elite athletes, yet only recently embraced by sport organizations as an important part of training and recovery. Sleep plays a crucial role in physical and cognitive performance and is an important factor in reducing risk of injury. This article aims to highlight the prevalence of poor sleep, describe its impacts, and address the issue of sport culture surrounding healthy sleep.

Relationships between Post-Concussion Sleep and Symptom Recovery: A Preliminary Study

Post-concussion sleep disturbances can be debilitating and may influence days to symptom recovery; however, evidence is minimal. The purpose of this study was to explore relationships between days to symptom recovery and aspects of sleep, as measured by actigraphy and subjective sleep questionnaires in a concussed sample. Thirty-one college students were physician-diagnosed with a concussion and asked to complete a daily sleep symptom checklist. Participants (n = 14) were excluded based on lack of compliance/early termination (22.6%), recorded <5 nights of data (12.9%), and protracted recoveries (3.2%). Final concussed sample included 17 college-aged students (varsity student-athletes, n = 5; university students, n = 12). A wrist-worn ActiGraph GT9X Link was provided during initial evaluation (within 72 h post-injury) and worn continuously until symptom recovery (follow-up evaluation; 14.3 ± 5.9 days post-injury). The Pittsburgh Sleep Quality Index (PSQI) and Epworth Sleepiness Scale (ESS) also were completed at follow-up. Pearson's correlations were conducted to determine relationships between days to symptom recovery and actigraphy sleep outcomes (sleep onset latency, wake after sleep onset (WASO_norm), total sleep time, sleep efficiency (SE), and number of awakenings) across recovery stages (2-3 days post-injury, mid-point, and end). Spearman's rho correlations were used to determine relationships between subjective sleep (PSQI global), sleepiness (ESS total), and sleep cluster symptom severity and days to symptom recovery. At recovery mid-point, individuals who were awake longer throughout the night (24.1 ± 9.0%) and/or were less efficient at sleeping (73.7 ± 9.7%) took longer to recover (WASO_norm: r = 0.58, p = 0.015; SE: r = -0.51, p = 0.035). Poorer post-concussion sleep quality (based on PSQI) was correlated with longer recovery (r_s = 0.70, p = 0.001). Post-concussion sleep-wake disturbances at recovery mid-point and overall poorer sleep quality may be associated with longer symptom recovery. Our findings provide preliminary guidance on identifying those who may be at risk for longer recoveries based on poorer sleep post-injury.

Quantifying Activity Levels After Sport-Related Concussion Using Actigraph and Mobile (mHealth) Technologies

CONTEXT

Interest in identifying the effects of physical and mental activity on recovery after sport-related concussion is growing. Clinical studies of concussed athletes' activities require well-validated methods for tracking their intensity and timing.

OBJECTIVE

To develop and validate a novel multimodal approach to monitoring activity postconcussion using mobile (mHealth) technologies.

DESIGN

Cohort study.

SETTING

Translational research unit.

PATIENTS OR OTHER PARTICIPANTS

A total of 40 high school and collegiate football players were evaluated at preseason and followed longitudinally after either concussion (n = 25; age = 17.88 ± 1.74 years, height = 182.07 ± 8.08 cm, mass = 98.36 ± 21.70 kg) or selection as a nonconcussed control (n = 15; age = 18.27 ± 1.83 years, height = 180.01 ± 7.19 cm, mass = 93.83 ± 24.56 kg).

MAIN OUTCOME MEASURE(S)

Participants wore a commercial actigraph and completed a daily mobile survey for 2 weeks. Analyses focused on comparisons between groups for actigraph-based physical activity and self-reported physical and mental activity during the follow-up period.

RESULTS

For the first 2 days postinjury, objective measures showed fewer daily steps in concussed (6663 ± 2667 steps) than in control (11 148 ± 3381 steps) athletes (P < .001), and both objective and self-reported measures indicated less moderate to vigorous physical activity in concussed (27.6 ± 32.6 min/d and 25.0 ± 43.6 min/d, respectively) than in control (57.3 ± 38.6 min/d and 67.5 ± 40.1 min/d, respectively) athletes (both P values < .05). Correlations between objective and self-reported measures of moderate to vigorous physical activity were moderate across select 1-week and 2-week averages. We observed no group differences in self-reported mental activities.

CONCLUSIONS

Physical activity after sport-related concussion varied widely across athletes but on average was reduced during the acute and early subacute postinjury periods for both objective and self-reported measures. The lack of differences in mental activities between groups may reflect limited change in mental exertion postconcussion or difficulty accurately measuring mental activities. Assessing concussed athletes' activities using actigraphy and self-reported scales may help monitor their compliance with activity recommendations and be useful in studies aimed at better understanding the effects of physical activity on concussion recovery.

Can Off-Training Physical Behaviors Influence Recovery in Athletes? A Scoping Review

Recently, the attention on recovery in sport increased enormously although there is lack of scientific evidence on the role of lifestyle in terms of movement [i.e., physical behaviors (PBs)], apart from sleep. Few studies assessed physical activity (PA) and sedentary behavior (SB) in athletes. The aims of this scoping review were to answer to the following scientific questions: (1) How active/inactive are competitive athletes out of training? (2) Do off-training PBs affect recovery, performance, and health? (3) What strategies can be implemented to improve recovery using off-training PBs, apart from sleep? From 1,116 potentially relevant articles, nine were eligible for inclusion in this review. The main issues identified were related to the heterogeneity concerning the types of sports, age category, gender, competitive level, sample size, and instruments/devices adopted, the paucity of studies investigating the effects of PBs while awake on recovery, and the lack of experimental designs manipulating PBs while awake to accelerate recovery. Furthermore, PA and SB domains were rarely investigated, while no research articles focused on the combined effect of 24-h PBs. Eight out of nine studies measured PA, seven SB, and two included sleep. Three studies included training practice into PA measurement by the means of accelerometry. Overall, almost the totality of the athletes achieved recommended PA levels although they sustained prolonged SB. In conclusion, more descriptive researches are needed in different athletic populations and settings. Furthermore, experimental designs aimed at investigating the effects of PBs manipulation on recovery and the putative mechanisms are encouraged.

Insomnia and daytime sleepiness: risk factors for sports-related concussion

OBJECTIVE/BACKGROUND

Poor quality and inadequate sleep are associated with impaired cognitive, motor, and behavioral components of sport performance and increased injury risk. While prior work identifies sports-related concussions as predisposing factors for poor sleep, the role of sleep as a sports-related concussion risk factor is unknown. The purpose of this study was to quantify the effect of poor sleep quality and insomnia symptoms on future sports-related concussion risk.

PATIENTS/METHODS

In this study, 190 NCAA Division-1 athletes completed a survey battery, including the Insomnia Severity Index (ISI) and National Health and Nutrition Examination Survey (NHANES) Sleep module. Univariate risk ratios for future sports-related concussions were computed with ISI and NHANES sleepiness scores as independent predictors. An additional multiple logistic regression model including sport, sports-related concussion history, and significant univariate predictors jointly assessed the odds of sustaining a concussion.

RESULTS

Clinically moderate-to-severe insomnia severity (RR = 3.13, 95% CI: 1.320-7.424, p = 0.015) and excessive daytime sleepiness two or more times per month (RR = 2.856, 95% CI: 0.681-11.977, p = 0.037) increased concussion risk. These variables remained significant and comparable in magnitude in a multivariate model adjusted for sport participation.

CONCLUSION

Insomnia and daytime sleepiness are independently associated with increased sports-related concussion risk. More completely identifying bidirectional relationships between concussions and sleep requires further research. Clinicians and athletes should be cognizant of this relationship and take proactive measures - including assessing and treating sleep-disordered breathing, limiting insomnia risk factors, improving sleep hygiene, and developing daytime sleepiness management strategies - to reduce sports-related concussion risk and support overall athletic performance.