Investigation of Aerobic and Muscular Fitness and Concussion Among Service Academy Cadets at the United States Air Force Academy: Results from the CARE Consortium

ABSTRACT Introduction Concussion has become the signature injury facing the U.S. military. However, little is understood about the relationship between military fitness and concussion recovery. The current study examined the recoveries of cadets at a U.S. Service Academy to determine whether preinjury physical fitness improved recovery and whether recovery was associated with post-injury physical fitness measures. Methods Participants were enrolled in a longitudinal study of concussion. Aerobic Fitness Test (AFT) and Physical Fitness Test (PFT) data were used to estimate cadet fitness. Survival analysis evaluated significant estimators of concussion recovery time. Linear regression models were used to explore the relationship between recovery duration and change in physical fitness scores. Results Between 2014 and 2017, 307 (n = 70; 22.80% Women) cadets who had sustained a concussion were enrolled. Preinjury physical fitness was not significantly associated with recovery duration (P > .05). Men and intercollegiate cadets took fewer days to reach recovery milestones. Compared to women, men had greater decrements in the Aerobic Fitness Test total score (P < .05) and increased 1.5-mile time postconcussion (P < .05). Women had greater decreases in push-ups postconcussion compared to males (P < .05). There was a trend for a negative association between days until asymptomatic and change in the Physical Fitness Test score (P = .07). Conclusion Preconcussion physical fitness levels do not appear to impact concussion recovery time among a highly physically fit cohort. Possible methods to reduce the effect of symptom duration on strength-related physical fitness should be investigated along with evaluating reductions in strength as a possible mechanism for postconcussion injury risk.

Variations in Time to Recovery from Pediatric Concussion Based on Differing Outcomes of Interest

ObjectiveTo quantify variability in pediatric concussion recovery across multiple outcomes of interest.BackgroundPediatric concussion studies are hindered by a common significant limitation: lack of agreement on a standard definition of “recovery.” A variety of clinical outcomes of interest utilized across studies, including symptom self-report, neurocognitive testing results, self-reported return to activity, and physician clearance for activity, leads to challenges for both research, as well as clinical concussion management.Design/MethodsWe enrolled concussed youth, ages 11–18 years, from a specialty sports medicine clinic = 28 days of injury. Patients were followed as part of clinical care for concussion for up to 13 weeks. At each visit, participants completed questionnaires and a battery of clinical measures. From these data, we constructed 10 potential definitions of recovery: 3 based on self-reported symptoms (change from pre-injury, no symptoms, below pre-determined thresholds), 2 based on visio-vestibular examination (VVE) deficits (none, = 1), 2 based on physician clearance (for return to school/sport), and 3 based on self-assessment (“back to normal”, return to school/exercise).ResultsOne hundred seventy-four concussed youth were enrolled (median age: 15 years, 54.6% female) with a median time from injury to initial visit of 12 days (IQR: 7, 20). Median number of visits was 2 (range: 1, 5). We observed a wide variation in the proportion of participants recovered across the 10 definitions. Depending on definition, between 4% and 45% were considered recovered within 4 weeks, and between 10% and 80% were considered recovered at the end of follow-up. The VVE-based definition (=1 deficit) consistently had the highest proportion recovered at all time points, while self-reported return to exercise had the lowest proportion.ConclusionsRecovery from concussion is not a single unitary point in time. These results will provide valuable guidance to clinicians in managing concussion and researchers in designing future observational and interventional trials of pediatric concussion.

The Effects of Concussion on Quantity and Quality of Sleep in Football Athletes

ObjectiveThe objective was to observe the quantity and quality of sleep of collegiate athletes following a concussion.BackgroundPatients diagnosed with a concussion report a disruption or change in their sleep with 46% of patients still having sleep disturbances 3 months after the event. Research is lacking on the sleep disruption or sleep changes in athletes who have experienced a concussion.Design/MethodsThis IRB-approved convenient cohort study involved athletes from 2 local universities. 27 (20 non-concussed and 7 concussed) male collegiate football players (19.93 ± 1.14 years old, 1.82 ± 0.08 m, and 96.42 ± 21.26 kg) wore a Readiband device for 7–10 days or throughout concussion recovery. Concussed participants completed a symptom score sheet each day. Participants returned the Readiband device and completed the Pittsburgh Sleep Quality Index Questionnaire (PSQIQ) after 7–10 days or on return to play. The sleep parameters, and PSQIQ scores were analyzed using non-parametric & independent t-tests with the alpha level set at 0.05.ResultsThe t-tests indicated a difference between the total minutes in bed at the initial measurement (F = 11.839, df = 1, p = 0.037) between the concussed (353.29 ± 110.48 minutes) and non-concussed (471.5 ± 125.09 minutes) groups. There was also a difference between the total minutes asleep at the initial measurement (F = 12.662, df = 1, p = 0.032) between the concussed (286.43 ± 86.73) and non-concussed groups (383.7 ± 104.86). The last measurement that indicated a difference was the calculated minutes in bed at the initial measurement (F = 11.916, df = 1, p = 0.023) between the concussed (326.4 3 ± 97.01) and non-concussed groups (441.60 ± 110.55).ConclusionsThe study results indicate that concussion affects the quantity of sleep, with concussed athletes spending less time in bed and fewer minutes asleep. Changes in sleep occur post-concussion, which may delay concussion recovery.

ADHD and DIRAS Single Nucleotide Polymorphism as an Indicator of Prolonged Concussion Recovery

The purpose of this study was to determine the association between the presence of a single nucleotide polymorphism (SNP; rs1412005) within DIRAS2 (i.e., a gene associated with attention-deficit/hyperactivity disorder (ADHD) and prolonged recovery following a sport-related concussion. A case-control study design was implemented, where cases and controls were selected from a cohort of 117 deidentified concussed athletes. Eleven samples from this patient cohort self-reported ADHD diagnosis and were age and sex-matched to 22 participants with no self-reported ADHD diagnoses. The average recovery times were 21.50 + 13.96 days and 15.66 + 8.50 days for the case and control groups, respectively. The authors found that only 13.6% of the individuals without an ADHD diagnosis recovered in > 30 days (p = 0.044). Also, the authors found that 72.7% of the carriers of the T allele (i.e., minor allele) recovered in greater than 30 days (p = 0.213). Researchers concluded that individuals with ADHD had a higher risk of prolonged concussion recovery lasting greater than 30 days. Also, carrying the rare allele was associated with prolonged recovery, which suggests this SNP could be a potential genetic marker for both prolonged concussion recovery and the presence of ADHD.

Longer Neurophysiological vs. Clinical Recovery Following Sport Concussion

Objectives: The objective of this study was to assess if injury-related alterations in the Sport Concussion Assessment Tool-5 (SCAT5) are matched by changes in transcranial magnetic stimulation-derived intracortical inhibition. We hypothesised that neurophysiological measures would take longer to return to normal than recovery assessed by the SCAT5 following sport related concussion (SRC).Methods: Thirteen male contact sport athletes (20.5 ± 4.5 years), who reported a concussion were recruited from local Rugby and American football clubs. Participants were tested at 4 timepoints throughout the concussion recovery period: within 24 h of concussion (day 0), and at 7, 9, and 11 days after concussion. All participants completed the SCAT5 and underwent TMS to assess cortical silent period duration (CSp), a measure of intracortical inhibition.Results: After concussion CSp significantly declined from day 0 (122 ± 28 ms) to day 11 (106 ± 15 ms) [F(3, 33) = 7.80, p < 0.001]. SCAT5 measures of symptom number and severity were significantly decreased [symptom number: χ(3)2 = 30.44, p < 0.01; symptom severity: χ(3)2 = 25.75, p < 0.001] between the day 0 timepoint and each of the other timepoints. SCAT5 balance errors (mBESS) decreased significantly [F(3, 33) = 19.55, p < 0.001] between the day 0 timepoint and each of the other timepoints. CSp and SCAT5 recovery patterns were different. SCAT5 domains recovered faster showing no further significant changes after day 7, whilst CSp was still decreasing between days 7 and 9. Due to the small sample size we also used a Bayesian linear model to investigate the recovery of CSp and mBESS. The posterior distribution of our Bayesian model provided evidence that CSp decreased at day 7 and it continued to decrease at day 9, unlike mBESS which decreased at day 7 and then reached a plateau.Conclusion: There are clinically important discrepancies between clinical and neurophysiological measures of concussion recovery. This finding has important implications for return to play (RTP) protocols and the prevention of complications after sport concussion.

An Evaluation of Omega-3 Status and Intake in Canadian Elite Rugby 7s Players

Background: EPA and DHA n-3 FA play crucial roles in both neurological and cardiovascular health and high dietary intakes along with supplementation suggest potential neuroprotection and concussion recovery support. Rugby athletes have a high risk of repetitive sub-concussive head impacts which may lead to long-term neurological deficits, but there is a lack of research looking into n-3 FA status in rugby players. We examined the dietary n-3 FA intake through a FFQ and n-3 FA status by measuring the percentage of n-3 FA and O3I in elite Canadian Rugby 7s players to show distribution across O3I risk zones; high risk, <4%; intermediate risk, 4 to 8%; and low risk, >8%. Methods: n-3 FA profile and dietary intake as per FFQ were collected at the beginning of the 2017–2018 Rugby 7s season in male (n = 19; 24.84 ± 2.32 years; 95.23 ± 6.93 kg) and female (n = 15; 23.45 ± 3.10 years; 71.21 ± 5.79 kg) athletes. Results: O3I averaged 4.54% ± 1.77, with female athlete scores slightly higher, and higher O3I scores in supplemented athletes (4.82% vs. 3.94%, p = 0.183), with a greater proportion of non-supplemented athletes in the high-risk category (45.5% vs. 39.1%). Dietary intake in non-supplemented athletes did not meet daily dietary recommendations for ALA or EPA + DHA compared to supplemented athletes. Conclusions: Overall, despite supplementation, O3I score remained in the high-risk category in a proportion of athletes who met recommended n-3 FA dietary intakes, and non-supplemented athletes had a higher proportion of O3I scores in the high-risk category, suggesting that dietary intake alone may not be enough and athletes may require additional dietary and n-3 FA supplementation to reduce neurological and cardiovascular risk.