Concussion history and virtual reality metrics predict core or lower extremity injury occurrence among high school athletes.

Introduction: A history of concussion is recognized as a risk factor for musculoskeletal injury, which is likely associated with physiological effects that warrant better understanding. This study aimed to assess the potential of measurements obtained from an immersive virtual reality (VR) test to identify a subtle perceptual-motor impairment that may be prospectively associated with the occurrence of a core or lower extremity sprain or strain. Methods: A cohort of 68 high school athletes (41 female soccer players and 27 male football players) provided survey responses and completed an immersive VR test several days prior to the initiation of preseason practice sessions. Measurements of eye, neck, arm, and whole-body displacements were obtained during 40 successive lunging/reaching responses to visual stimuli moving horizontally across the VR headset display. Injury occurrences were electronically documented from the initial preseason practice session to the final game of the season. Results: A statistically significant and intrinsically credible two-factor prediction model for core or lower extremity injury occurrence included an interaction between female sex and a self-reported history of two or more concussions, along with slow response time (RT) for arm reach (OR = 4.67; 95% CI, 1.51-14.43). Follow-up analyses identified sex-specific cut points for arm reach RT associated with elevated injury risk, which were ≥1.385 s for females and ≥1.257 s for males. Discussion: High school female soccer players who have sustained more than one concussion appear to be highly vulnerable to core or lower extremity sprain or strain, with the risk of injury compounded by a slow arm reach RT. Male football players as a group demonstrated significantly faster arm reach RT than that of female soccer players, but slow perceptual-motor RT for arm reach was also identified as a potentially important injury risk factor for male players. Immersive VR appears to provide precise measurements of behavioral performance characteristics that depend on brain processing efficiency. Given that the speed, accuracy, and consistency of perceptual-motor responses may be modifiable, future research should explore the potential benefits of VR training for reducing the risk of sport-related injuries.

Assessment and Training of Perceptual-Motor Function: Performance of College Wrestlers Associated with History of Concussion.

Concussion may affect sport performance capabilities related to the visual perception of environmental events, rapid decision-making, and the generation of effective movement responses. Immersive virtual reality (VR) offers a means to quantify, and potentially enhance, the speed, accuracy, and consistency of responses generated by integrated neural processes. A cohort of 24 NCAA Division I male wrestlers completed VR assessments before and after a 3-week VR training program designed to improve their perceptual-motor performance. Prior to training, the intra-individual variability (IIV) among 40 successive task trials for perceptual latency (i.e., time elapsed between visual stimulus presentation and the initiation of movement response) demonstrated strong discrimination between 10 wrestlers who self-reported a history of concussion from 14 wrestlers who denied ever having sustained a concussion (Area Under Curve ≥ 0.750 for neck, arm, and step movements). Natural log transformation improved the distribution normality of the IIV values for both perceptual latency and response time (i.e., time elapsed between visual stimulus presentation and the completion of movement response). The repeated measures ANOVA results demonstrated statistically significant (p < 0.05) pre- and post-training differences between groups for the IIV in perceptual latency and the IIV in response time for neck, arm, and step movements. Five of the six IIV metrics demonstrated a statistically significant magnitude of change for both groups, with large effect sizes. We conclude that a VR assessment can detect impairments in perceptual-motor performance among college wrestlers with a history of concussion. Although significant post-training group differences were evident, VR training can yield significant performance improvements in both groups.

The relationship between physical activity, stress, and resilience in sexual and gender minority college students.

OBJECTIVE: To assess the role of sexual orientation and gender identity in the relationship between physical activity (PA), stress and resilience. PARTICIPANTS: A nationally-representative sample of students (n = 91,718) from United States postsecondary institutions. METHODS: Students reported aerobic and strength training (ST) behaviors, stress, resilience, gender identity and sexual orientation. Moderated regressions examined the influence of gender identity and sexual orientation on the relationship between PA and stress or resilience. RESULTS: Men and heterosexual students reported higher PA and resilience and lower stress than did women, gender minorities, and sexual minorities. Significant moderation was found for women, queer students, bisexual students, trans women and lesbians in the various models. CONCLUSIONS: Gender minority and sexual minority students display poorer levels of PA and mental health than cisgender and heterosexual counterparts, but this relationship varies by identity group.

Subtle impairments of perceptual-motor function and well-being are detectable among military cadets and college athletes with self-reported history of concussion.

Introduction: A lack of obvious long-term effects of concussion on standard clinical measures of behavioral performance capabilities does not preclude the existence of subtle neural processing impairments that appear to be linked to elevated risk for subsequent concussion occurrence, and which may be associated with greater susceptibility to progressive neurodegenerative processes. The purpose of this observational cohort study was to assess virtual reality motor response variability and survey responses as possible indicators of suboptimal brain function among military cadets and college athletes with self-reported history of concussion (HxC). Methods: The cohort comprised 75 college students (20.7 ± 2.1 years): 39 Reserve Officer Training Corp (ROTC) military cadets (10 female), 16 football players, and 20 wrestlers; HxC self-reported by 20 (29.2 ± 27.1 months prior, range: 3-96). A virtual reality (VR) test involving 40 lunging/reaching responses to horizontally moving dots (filled/congruent: same direction; open/incongruent: opposite direction) was administered, along with the Sport Fitness and Wellness Index (SFWI) survey. VR Dispersion (standard deviation of 12 T-scores for neck, upper extremity, and lower extremity responses to congruent vs. incongruent stimuli originating from central vs. peripheral locations) and SFWI response patterns were the primary outcomes of interest. Results: Logistic regression modeling of VR Dispersion (range: 1.5-21.8), SFWI (range: 44-100), and an interaction between them provided 81% HxC classification accuracy (Model χ 2[2] = 26.03, p < .001; Hosmer & Lemeshow χ 2[8] = 1.86, p = .967; Nagelkerke R 2 = .427; Area Under Curve = .841, 95% CI: .734, .948). Binary modeling that included VR Dispersion ≥3.2 and SFWI ≤86 demonstrated 75% sensitivity and 86% specificity with both factors positive (Odds Ratio = 17.6, 95% CI: 5.0, 62.1). Discussion/Conclusion: Detection of subtle indicators of altered brain processes that might otherwise remain unrecognized is clearly important for both short-term and long-term clinical management of concussion. Inconsistency among neck, upper extremity, and lower extremity responses to different types of moving visual stimuli, along with survey responses suggesting suboptimal well-being, merit further investigation as possible clinical indicators of persisting effects of concussion that might prove to be modifiable.

Changes in dual-task cognitive performance elicited by physical exertion vary with motor task.

Background: Integrated movement and cognitive load paradigms are used to expose impairments associated with concussion and musculoskeletal injury. There is currently little information on the discriminatory nature of dual-task complexity and the relative influence of physical exertion on cognitive outcomes. Purpose: Assess cognitive performance while under motor conditions of increasing complexity before and after a standardized exercise protocol. Methods: 34 participants were recruited (17 male and 17 female; 24 ± 1.4 yrs). A modified Eriksen flanker test was used to assess cognitive performance under four conditions (seated, single-leg stance, walking, and lateral stepping) before and after a 20-min moderate-to vigorous intensity treadmill protocol. The flanker test consisted of 20 sets of 5-arrow configurations, appearing in random order. To complete the response to cognitive stimulus, participants held a smartphone horizontally and were instructed to respond as quickly and as accurately as possible by tilting the device in the direction corresponding to the orientation of the middle arrow. The metrics used for analysis included average reaction time (ms), inverse efficiency index (average reaction time penalized for incorrect responses), and conflict effect (the average time cost of responding to an incongruent repetition vs. a congruent repetition). Mixed effects (condition by time) RMANOVAs were conducted to examine the effects of motor task complexity and physical exertion on cognitive performance. Results: There was a condition by time interaction for inverse efficiency index (p < 0.001), in which participants displayed higher cognitive efficiency for the pre-activity lateral stepping condition compared to the other three conditions (Cohen's d = 1.3-1.6). For reaction time and conflict effect, there were main effects for condition (p = 0.004 and 0.006, respectively), in which performance during lateral stepping was improved in relation to the seated condition (reaction time Cohen's d = 0.68; conflict effect Cohen's d = 0.64). Conclusion: Participants tended to display better dual-task cognitive performance under more stimulating or complex motor tasks before physical exertion, likely associated with the inverted-U arousal-performance relationship. When using dual-task assessments, clinicians should be mindful of the accompanying motor task and baseline exertion levels and their potential to disrupt or optimize cognitive performance.

Reliability and concurrent validity of TRAZER compared to three-dimensional motion capture.

BACKGROUND: Efficient neural processing of visuospatial and proprioceptive input appears to be crucial for avoidance of sport injury. As such, clinically-feasible tests are needed to identify deficiencies found by advanced neuroimaging and electrophysiological tests. Three-dimensional motion capture in a laboratory setting is currently the gold standard for measurement of human movement parameters but is costly and requires extensive training. Non-immersive virtual reality systems with body motion tracking, such as TRAZER, may provide a clinically-feasible and portable means of acquiring similar variables. Test-retest reliability and concurrent validity of these systems are currently lacking. AIM: The aim of the study was to assess the concurrent validity of the TRAZER single-camera system with 3D motion capture system and to assess the test-retest reliability of TRAZER's whole-body reactive agility metrics. METHODS: Participants - For validity, 13 healthy individuals (24.8±3.1 years, 170.0±7.7 cm, 70.0±14.2 kg); for reliability, 18 healthy individuals (23.3±2.5 years, 168.2±11.2 cm, 78.2±17.8 kg). Design - Validity was a single-session cross-sectional study. Reliability was a 3 consecutive day test-retest study. Setting-Controlled laboratory study. Intervention - Assessments utilized randomized movements in eight directions for forty total repetitions as designated by the TRAZER system. TRAZER protocol was simultaneously tracked by Vicon Motion Capture and the TRAZER system. Reliability data were captured on three consecutive days by the TRAZER system. Main Outcome Measures - Maximum acceleration, maximum velocity, and total distance were recorded for validation. In addition to these measures, maximum deceleration, average velocity, average acceleration, average deceleration, and average reaction time were collected for reliability. RESULTS: Overall, a lack of agreement exists between maximum outputs for TRAZER and 3D motion capture (velocity r=0.808, acceleration r=-0.090), but total distance correlation was high (r =.961). ICC values between days 1-2-3 for average measures were high (average velocity=0.847, average acceleration=0.919, and average deceleration=0.948) with the exception of average reaction time being fair (ICC=0.536). ICCs for maximum measures showed a much smaller correlation between days (velocity=0.654, acceleration=0.171, and deceleration=0.416). CONCLUSIONS: Even though there is a lack of strong concurrent validity between measures obtained from TRAZER and 3D motion capture systems, there is strong test-retest reliability of the TRAZER system. The applicability of these findings makes TRAZER clinically relevant in scenarios requiring pre- and post-testing for return to play decisions, or monitoring of a training regimen where demonstration of validation to a gold standard measurement is not relevant. RELEVANCE FOR PATIENTS: When test-retest capability is desired, such as in return-to-play protocols following an injury, Trazer is a reliable option.