A Framework for Concussion Management Strategies in Law Enforcement Officers.

Athletic trainers are increasingly utilized in non-traditional settings, such as in law enforcement, where they can contribute to healthcare management, including concussion management of law enforcement officers (LEOs). Despite the prevalence of concussions among LEOs, there is a notable gap in concussion management guidelines for this population. LEOs may lack the education and resources necessary for concussion recognition and proper management. Drawing on advancements in concussion management in athletes and military personnel, here we present a comprehensive framework for concussion management in LEOs encompassing concussion education, a graduated return to duty (RTD) protocol, and considerations for implementation and documentation specific to law enforcement. We also present several barriers and facilitators to implementation. Due to job requirements, it is critical for law enforcement organizations and their medical providers to adopt a concussion management strategy. Without proper concussion management, LEOs may risk subsequent injury and/or suffer from prolonged recovery and adverse long-term outcomes.

Models of Video Feedback for Youth Athletes Performing an American Football Tackle.

CONTEXT: Video feedback is an expeditious method for improving athlete safety when performing activities with an inherent risk of injury. Providing appropriate and validated feedback during tackling training in American football may be a mechanism for athletes to learn safe tackling performance. OBJECTIVE: To determine the effect of video feedback in the instruction of tackling form. DESIGN: Controlled laboratory study. SETTING: Laboratory. PATIENTS OR OTHER PARTICIPANTS: A total of 32 youth football athletes (28 boys, 4 girls; age = 11.8 ± 0.8 years) participated in 1 day of training. Of those, 14 participants completed 2 additional days of training and a 48-hour retention and transfer test. INTERVENTION(S): Video feedback using self as model, expert as model, combined self and expert model, and oral feedback to promote safe tackling performance in a laboratory environment. MAIN OUTCOME MEASURE(S): Shoulder extension, cervical extension, trunk angle, pelvis height, and step length by training block and over time. RESULTS: For the 1-day training group, main effects for time were observed for shoulder extension (P < .01), cervical extension (P = .01), pelvis height (P < .01), and step length (P < .01), with better performance for pelvis height and step length after combined feedback. For the 3-day training group, main effects of time were identified in pelvis height (P < .01) and step length (P < .01), with combined feedback showing better performance than other methods in shoulder extension and pelvis height. Combined feedback resulted in better performance compared with its component parts and oral feedback alone. In the combined model, participants viewed both their performance and the expert model, enabling them to see the difference between current and required performance. CONCLUSIONS: Combined feedback may be superior to other forms of feedback in improving movement performance. This effect can be generalized across disciplines that provide instruction and feedback in movement.

Organization of sensorimotor activity in anterior cruciate ligament reconstructed individuals: an fMRI conjunction analysis.

Introduction: Anterior cruciate ligament reconstruction (ACLR) is characterized by persistent involved limb functional deficits that persist for years despite rehabilitation. Previous research provides evidence of both peripheral and central nervous system adaptations following ACLR. However, no study has compared functional organization of the brain for involved limb motor control relative to the uninvolved limb and healthy controls. The purpose of this study was to examine sensorimotor cortex and cerebellar functional activity overlap and non-overlap during a knee motor control task between groups (ACLR and control), and to determine cortical organization of involved and uninvolved limb movement between groups. Methods: Eighteen participants with left knee ACLR and 18 control participants performed a knee flexion/extension motor control task during functional magnetic resonance imaging (fMRI). A conjunction analysis was conducted to determine the degree of overlap in brain activity for involved and uninvolved limb knee motor control between groups. Results: The ACLR group had a statistically higher mean percent signal change in the sensorimotor cortex for the involved > uninvolved contrast compared to the control group. Brain activity between groups statistically overlapped in sensorimotor regions of the cortex and cerebellum for both group contrasts: involved > uninvolved and uninvolved > involved. Relative to the control group, the ACLR group uniquely activated superior parietal regions (precuneus, lateral occipital cortex) for involved limb motor control. Additionally, for involved limb motor control, the ACLR group displayed a medial and superior shift in peak voxel location in frontal regions; for parietal regions, the ACLR group had a more posterior and superior peak voxel location relative to the control group. Conclusion: ACLR may result in unique activation of the sensorimotor cortex via a cortically driven sensory integration strategy to maintain involved limb motor control. The ACLR group's unique brain activity was independent of strength, self-reported knee function, and time from surgery.

Characterizing Head Acceleration Events in Law Enforcement Cadets During Subject Control Technique Training.

Law enforcement cadets (LECs) complete weeks of subject control technique training. Similar sport-related combat training has been shown to expose participants to head acceleration events (HAEs) that have potential to result in short- and long-term impairments. The purpose of this study was to describe the number and magnitude of HAEs in LECs throughout their training. 37 LECs (7 females; age = 30.6 ± 8.8 years; BMI = 30.0 ± 6.0) were recruited from a law enforcement organization. Participants wore instrumented mouthguards, which recorded all HAEs exceeding a resultant 5 g threshold for training sessions with the potential for HAEs. Participants completed three defensive tactics (DT) training sessions, a DT skill assessment (DTA), and three boxing sessions. Outcome measures included the number of HAEs, peak linear acceleration (PLA), and peak rotational velocity (PRV). There were 2758 true-positive HAEs recorded across the duration of the study. Boxing sessions accounted for 63.7% of all true-positive HAEs, while DT accounted for 31.4% and DTA accounted for 4.9%. Boxing sessions resulted in a higher number of HAEs per session (F2,28 = 48.588, p < 0.001, ηp2 = 0.776), and higher median PLA (F2,28 = 8.609, p = 0.001, ηp2 = 0.381) and median PRV (F2,28 = 11.297, p < 0.001, ηp2 = 0.447) than DT and DTA. The LECs experience a high number of HAEs, particularly during boxing sessions. Although this training is necessary for job duties, HAE monitoring may lead to modifications in training structure to improve participant safety and enhance recovery.

Estimating marksmanship performance during walking while maintaining weapon aim.

Marksmanship performance while moving is a critical skill among tactical athletes due to the high demands of their occupational duties. Qualifications for dynamic marksmanship performance are not standardized across tactical athlete groups, which may limit comprehensive assessment of tactical athlete performance for situational awareness and adaptability to an unpredictable environment. Although static marksmanship performance provides foundational information on skills and level of ability, research is lacking on factors that influence dynamic marksmanship performance to best prepare tactical athletes for duties. The purpose of this study was to identify whether static marksmanship performance, speed of movement, load carriage, and biomechanical factors while 'shooting on the move' influenced dynamic marksmanship performance. Twenty-four male tactical athletes (22 active-duty Army Soldiers, two civilian SWAT operators; age: 23.83 ± 5.47 years; height: 1.80 ± 0.08 m; weight: 81.04 ± 7.87 kg) participated; final analyses did not include data from the two civilian operators to maintain sample homogeneity. Tactical athletes completed static and dynamic ('shoot on the move') marksmanship tasks under three load conditions: (1) no load (NL), (2) half kit (HK) of 11.34 kg, and (3) full kit (KIT) of 22.68 kg. Dynamic marksmanship was completed under three speed conditions: (1) self-selected slow speed, (2) standard speed, and (3) self-selected fast speed. Hip, knee, and ankle kinematics were collected via wireless inertial measurement units. Spatiotemporal parameters were collected via optical detection system. Marksmanship performance (accuracy) was collected via open-air acoustic target scoring and mean radial error (MRE) was calculated for both static and dynamic marksmanship tasks. Linear mixed-effects models were fit with dynamic MRE as the outcome variable with fixed effects of static MRE, load condition, speed condition, kinematics, and spatiotemporal parameters, adjusting for body mass. Alpha level was set a priori at p ≤ 0.10. The final statistical model included fixed effects of static MRE, load condition, speed condition, and time spent in double limb support. Static MRE (p < 0.01) and time spent in double limb support (p = 0.01) were significant factors. For each 1 cm increase in static MRE there was a 0.66 cm increase in dynamic MRE. For every 1% increase in time spent in double limb support while 'shooting on the move' there was a 0.13 cm increase in dynamic MRE. Findings from this study highlight that tactical athletes who have larger static stance MRE and spend a longer time in double limb support during a gait cycle exhibit an increase in MRE during 'shoot on the move' trials. Overall, dynamic shooting accuracy is not affected by lower extremity joint angles, load carriage, or speed of movement. Although strong relationships are known between gait speed, load, and lower extremity kinematics, the differences in tactical gait compared to normal gait and multi-task paradigm that likely favors marksmanship accuracy seem to present novel movement characteristics unique to occupational gait. Further investigation is warranted to identify other potential factors that may improve or worsen dynamic marksmanship performance.

Brain activity associated with quadriceps strength deficits after anterior cruciate ligament reconstruction.

Prolonged treatment resistant quadriceps weakness after anterior cruciate ligament reconstruction (ACL-R) contributes to re-injury risk, poor patient outcomes, and earlier development of osteoarthritis. The origin of post-injury weakness is in part neurological in nature, but it is unknown whether regional brain activity is related to clinical metrics of quadriceps weakness. Thus, the purpose of this investigation was to better understand the neural contributions to quadriceps weakness after injury by evaluating the relationship between brain activity for a quadriceps-dominated knee task (repeated cycles of unilateral knee flexion/extension from 45° to 0°), , and strength asymmetry in individuals returned to activity after ACL-R. Forty-four participants were recruited (22 with unilateral ACL reconstruction; 22 controls) and peak isokinetic knee extensor torque was assessed at 60°/s to calculate quadriceps limb symmetry index (Q-LSI, ratio of involved/uninvolved limb). Correlations were used to determine the relationship of mean % signal change within key sensorimotor brain regions and Q-LSI. Brain activity was also evaluated group wise based on clinical recommendations for strength (Q-LSI < 90%, n = 12; Q-LSI ≥ 90%, n = 10; controls, all n = 22 Q-LSI ≥ 90%). Lower Q-LSI was related to increased activity in the contralateral premotor cortex and lingual gyrus (p < .05). Those who did not meet clinical recommendations for strength demonstrated greater lingual gyrus activity compared to those who met clinical recommendations Q-LSI ≥ 90 and healthy controls (p < 0.05). Asymmetrically weak ACL-R patients displayed greater cortical activity than patients with no underlying asymmetry and healthy controls.

Comparing dynamic visual acuity between athletes who are deaf or hard-of-hearing and athletes who are hearing.

This study examined the difference in the dynamic visual acuity test (DVAT) between collegiate athletes who are deaf or hard-of-hearing (D/HoH) (n = 38) and university club-level athletes who are hearing (n = 38). Dynamic visual acuity was assessed using the Bertec Vision Advantage (Bertec® Corporation, Columbus, Ohio, USA). No statistically significant differences between athletes who are D/HoH and who are hearing were found in DVAT for leftward (χ2 = 0.71, p = 0.40) or rightward (χ2 = 0.04, p = 0.84) head yaw rotation around an earth vertical axis. Dynamic visual acuity was similar for athletes regardless of hearing status. Baseline DVAT data may be of use for post-injury management of athletes who are D/HoH.

The relationship between drop vertical jump action-observation brain activity and kinesiophobia after anterior cruciate ligament reconstruction: A cross-sectional fMRI study.

BACKGROUND: Injury and reconstruction of anterior cruciate ligament (ACL) result in central nervous system alteration to control the muscles around the knee joint. Most individuals with ACL reconstruction (ACLR) experience kinesiophobia which can prevent them from returning to activity and is associated with negative outcomes after ACLR. However, it is unknown if kinesiophobia alters brain activity after ACL injury. OBJECTIVES: To compare brain activity between an ACLR group and matched uninjured controls during an action-observation drop vertical jump (AO-DVJ) paradigm and to explore the association between kinesiophobia and brain activity in the ACLR group. METHODS: This cross-sectional study enrolled 26 individuals, 13 with ACLR (5 males and 8 females, 20.62 ± 1.93 years, 1.71 ± 0.1 m, 68.42 ± 14.75 kg) and 13 matched uninjured controls (5 males and 8 females, 22.92 ± 3.17 years, 1.74 ± 0.10 m, 70.48 ± 15.38 kg). Individuals were matched on sex and activity level. Participants completed the Tampa Scale of Kinesiophobia-11 (TSK-11) to evaluate the level of movement-related fear. To assay the brain activity associated with a functional movement, the current study employed an action-observation/motor imagery paradigm during functional magnetic resonance imaging (fMRI). RESULTS: The ACLR group had lower brain activity in the right ventrolateral prefrontal cortex relative to the uninjured control group. Brain activity of the left cerebellum Crus I and Crus II, the right cerebellum lobule IX, amygdala, middle temporal gyrus, and temporal pole were positively correlated with TSK-11 scores in the ACLR group. CONCLUSION: Brain activity for the AO-DVJ paradigm was different between the ACLR group and uninjured controls. Secondly, in participants with ACLR, there was a positive relationship between TSK-11 scores and activity in brain areas engaged in fear and cognitive processes during the AO-DVJ paradigm.

Hearing Status and Static Postural Control of Collegiate Athletes.

CONTEXT: Because of the close proximity of the cochlea, vestibular apparatus, and shared neurovascular structures, the static postural control of athletes who are deaf or hard of hearing (D/HoH) may be different from that of athletes who are hearing. Limited research is available to quantify differences between these athletes. OBJECTIVE: To determine the effect of hearing status and stance condition on the static postural control of athletes. DESIGN: Cross-sectional study. SETTING: Athletic training facilities. PATIENTS OR OTHER PARTICIPANTS: Fifty-five collegiate varsity athletes who were D/HoH (age = 20.62 ± 1.80 years, height = 1.73 ± 0.08 m, mass = 80.34 ± 18.92 kg) and 100 university club athletes who were hearing (age = 20.11 ± 1.59 years, height = 1.76 ± 0.09 m, mass = 77.66 ± 14.37 kg). MAIN OUTCOME MEASURE(S): Participants completed the Modified Clinical Test of Sensory Interaction and Balance on a triaxial force plate. Anteroposterior and mediolateral (ML) center-of-pressure (CoP) velocity, anteroposterior and ML CoP amplitude root mean square, and 95% ellipse sway area were calculated. RESULTS: Athletes who were D/HoH had a larger CoP velocity, larger ML root mean square, and larger sway area than those who were hearing (P values < .01). A significant main effect of stance condition was observed for all postural control variables (P values < .01). CONCLUSIONS: During the Modified Clinical Test of Sensory Interaction and Balance, athletes who were D/HoH demonstrated a larger sway area compared with athletes who were hearing. Therefore, individualized baseline assessments of static postural control may be warranted for athletes who are D/HoH as opposed to comparisons with existing normative data.

Neural Correlates of Self-Reported Knee Function in Individuals After Anterior Cruciate Ligament Reconstruction.

BACKGROUND: Anterior cruciate ligament (ACL) rupture is a common knee injury among athletes and physically active adults. Despite surgical reconstruction and extensive rehabilitation, reinjuries are common and disability levels are high, even years after therapy and return to activity. Prolonged knee dysfunction may result in part from unresolved neuromuscular deficits of the surrounding joint musculature in response to injury. Indeed, "upstream" neurological adaptations occurring after injury may explain these persistent functional deficits. Despite evidence for injury consequences extending beyond the joint to the nervous system, the link between neurophysiological impairments and patient-reported measures of knee function remains unclear. HYPOTHESIS: Patterns of brain activation for knee control are related to measures of patient-reported knee function in individuals after ACL reconstruction (ACL-R). STUDY DESIGN: Cross-sectional study. LEVEL OF EVIDENCE: Level 3. METHODS: In this multicenter, cross-sectional study, participants with unilateral ACL-R (n = 25; 10 men, 15 women) underwent task-based functional magnetic resonance imaging testing. Participants performed repeated cycles of open-chain knee flexion/extension. Neural activation patterns during the movement task were quantified using blood oxygen level-dependent (BOLD) signals. Regions of interest were generated using the Juelich Histological Brain Atlas. Pearson product-moment correlations were used to determine the relationship between mean BOLD signal within each brain region and self-reported knee function level, as measured by the International Knee Documentation Committee index. Partial correlations were also calculated after controlling for time from surgery and sex. RESULTS: Patient-reported knee function was positively and moderately correlated with the ipsilateral secondary somatosensory cortex (r = 0.57, P = 0.005) and the ipsilateral supplementary motor area (r = 0.51, P = 0.01). CONCLUSION: Increased ipsilateral secondary sensorimotor cortical activity is related to higher perceived knee function. CLINICAL RELEVANCE: Central nervous system mechanisms for knee control are related to subjective levels of knee function after ACL-R. Increased neural activity may reflect central neuroplastic strategies to preserve knee functionality after traumatic injury.

Normative Performance Profiles of College Aged Esport Athletes in a Pilot Study.

Aims: This study aimed to holistically assess the physical and cognitive attributes of esport athletes. Methods and Results: Forty-six adults between 18 and 32 years old with experience playing videogames were enrolled in this study. Participants completed assessments in five areas: demographics, self-report questionnaires, cognitive performance, physical performance, and gaming performance. Participants self-reported Overwatch ranking and physical activity participation (Pediatric Physical Activity Measure), and grip strength was measured with a handheld dynamometer. Seven domains of physical, mental, and social health and well-being were measured with the Patient Reported Outcomes Measurement Information System (PROMIS-29). The List Sorting Working Memory Test and Picture Sequence Memory Test from the National Institutes of Health (NIH) Toolbox Cognition Batteries were used to measure cognitive performance. Finally, esports performance was measured using a series of tasks through Alienware Academy and AIM Booster to record accuracy, reaction time, and targets hit. Participants were separated into high and low ranking groups for comparisons. This sample of esport athletes was similar to the general population for grip strength, each of the PROMIS-29 metrics, the List Sorting Working Memory Test, and the Picture Sequence Memory Test. Reaction time was the variable with the only significant difference between ranking groups. Conclusion: This study represents a primary investigation of esport athletes using a holistic approach. By incorporating physical and cognitive components, the most important factors to esport athletes' health and performance can be better understood and applied.

Arousal/Stress Effects of "Overwatch" eSports Game Competition in Collegiate Gamers.

ABSTRACT: Kraemer, WJ, Caldwell, LK, Post, EM, Beeler, MK, Emerson, A, Volek, JS, Maresh, CM, Fogt, JS, Fogt, N, Häkkinen, K, Newton, RU, Lopez, P, Sanchez, BN, and Onate, JA. Arousal/stress effects of "Overwatch" eSports game competition in collegiate gamers. J Strength Cond Res 36(10): 2671-2675, 2022-To date, no physical response data are available for one of the most popular eSport games, Overwatch . The purpose of this investigation was to describe the stress signaling associated with competitive Overwatch play and to understand how acute hormonal responses may affect performance. Thirty-two male college-aged gamers (age: 21.3 ± 2.7 years; estimated time played per week: 18 ± 15 hours) completed the study. Subjects were randomly assigned to a 6-player team to compete in a tournament-style match. Salivary measures of cortisol and testosterone were collected immediately before (PRE) and after (POST) the first-round game, with the heart rate recorded continuously during the match. The mean characteristics were calculated for each variable and comparisons made by the skill level. Significance was defined as p ≤ 0.05. There were no differences in measures of salivary cortisol. A differential response pattern was observed by the skill level for testosterone. The low skill group displayed a significant increase in testosterone with game play (mean ± SD , testosterone PRE: 418.3 ± 89.5 pmol·L -1 , POST: 527.6 ± 132.4 pmol·L -1 , p < 0.001), whereas no change was observed in the high skill group. There were no differences in heart rate characteristics between skill groups. Overall, the average heart rate was 107.2 ± 17.8 bpm with an average max heart rate of 133.3 ± 19.1 bpm. This study provides unique physiological evidence that a sedentary Overwatch match modulates endocrine and cardiovascular responses, with the skill level emerging as a potential modulator.

Clinical Utility and Validity of Exercise Vital Sign in Children.

ABSTRACT: We reviewed charts of 14,446 sports medicine patients, children aged 5 to 18 years, over a 3-year period to determine the discriminant validity of Exercise Vital Sign (EVS) questions. A logistic regression analyzed factors related to any moderate to vigorous physical activity (MVPA). A linear regression analyzed factors related to amount of MVPA for those who participated in any weekly MVPA. Overall, 48% of children reported meeting physical activity guidelines for 420 min·wk-1. Overall, children reported 400.36 ± 280.04 min·wk-1 of MVPA. Those with depression had significantly less MVPA than those without (95% confidence interval [CI], -96.65 to -26.31). Girls had significantly less MVPA than boys (95% CI, -59.15 to -40.31). Overweight and obese children reported less MVPA compared with normal weight children (95% CIs, -42.65 to -17.29 and -91.61 to -65.50, respectively). EVS demonstrates strong discriminant validity to detect differences between groups as a function of sex, body mass index, and depression.

Visual cognition associated with knee proprioception, time to stability, and sensory integration neural activity after ACL reconstruction.

Visual cognitive ability has previously been associated with anterior cruciate ligament injury and injury risk biomechanics in healthy athletes. Neuroimaging reports have identified increased neural activity in regions corresponding to visual-spatial processing, sensory integration, and visual cognition in individuals after anterior cruciate ligament reconstruction (ACLR), indicating potential neural compensatory strategies for motor control. However, it remains unclear whether there is a relationship between visual cognition, neural activity, and metrics of neuromuscular ability after ACLR. The purpose of this study was to (1) evaluate the relationship between visual cognitive function and measurements of neuromuscular control (proprioception and time to stability [TTS]), isokinetic strength, and subjective function, and (2) examine the neural correlates of visual cognition between ACLR (n = 16; time since surgery 41.4 ± 33.0 months) and demographically similar controls (n = 15). Visual cognition was assessed by the ImPACT visual motor and visual memory subscales. Outcome variables of proprioception to target knee angle 20°, landing TTS, strength, and subjective function were compared between groups, and visual cognition was correlated within groups to determine the relationship between visual cognition and outcome variables controlled for time from surgery (ACLR group). The control group had better IKDC scores and strength. Visual memory and visual motor ability were negatively associated with proprioception error (r = -0.63) and TTS (r = -0.61), respectively, in the ACLR group but not controls. Visual cognition was associated with increased neural activity in the precuneus and posterior cingulate cortex in the ACLR group but not control participants. These data suggest the neural strategy in which ACLR participants maintain proprioception and stability varies, and may depend on visual cognition and sensory integration neural activity.

Differences in brain structure and theta burst stimulation-induced plasticity implicate the corticomotor system in loss of function after musculoskeletal injury.

Traumatic musculoskeletal injury (MSI) may involve changes in corticomotor structure and function, but direct evidence is needed. To determine the corticomotor basis of MSI, we examined interactions among skeletomotor function, corticospinal excitability, corticomotor structure (cortical thickness and white matter microstructure), and intermittent theta burst stimulation (iTBS)-induced plasticity. Nine women with unilateral anterior cruciate ligament rupture (ACL) 3.2 ± 1.1 yr prior to the study and 11 matched controls (CON) completed an MRI session followed by an offline plasticity-probing protocol using a randomized, sham-controlled, double-blind, cross-over study design. iTBS was applied to the injured (ACL) or nondominant (CON) motor cortex leg representation (M1LEG) with plasticity assessed based on changes in skeletomotor function and corticospinal excitability compared with sham iTBS. The results showed persistent loss of function in the injured quadriceps, compensatory adaptations in the uninjured quadriceps and both hamstrings, and injury-specific increases in corticospinal excitability. Injury was associated with lateralized reductions in paracentral lobule thickness, greater centrality of nonleg corticomotor regions, and increased primary somatosensory cortex leg area inefficiency and eccentricity. Individual responses to iTBS were consistent with the principles of homeostatic metaplasticity; corresponded to injury-related differences in skeletomotor function, corticospinal excitability, and corticomotor structure; and suggested that corticomotor adaptations involve both hemispheres. Moreover, iTBS normalized skeletomotor function and corticospinal excitability in ACL. The results of this investigation directly confirm corticomotor involvement in chronic loss of function after traumatic MSI, emphasize the sensitivity of the corticomotor system to skeletomotor events and behaviors, and raise the possibility that brain-targeted therapies could improve recovery.NEW & NOTEWORTHY Traumatic musculoskeletal injuries may involve adaptive changes in the brain that contribute to loss of function. Our combination of neuroimaging and theta burst transcranial magnetic stimulation (iTBS) revealed distinct patterns of iTBS-induced plasticity that normalized differences in muscle and brain function evident years after unilateral knee ligament rupture. Individual responses to iTBS corresponded to injury-specific differences in brain structure and physiological activity, depended on skeletomotor deficit severity, and suggested that corticomotor adaptations involve both hemispheres.

Concussion Epidemiology in Athletes Who Are Deaf or Hard-of-Hearing Compared With Athletes Who Are Hearing.

OBJECTIVE: To compare the epidemiology of concussion between athletes who are deaf or hard-of-hearing (D/HoH) and athletes who are hearing. DESIGN: Descriptive epidemiology study. SETTING: Data were collected from 2 Division III athletic programs. One institution is the world's only university designed to be barrier-free for students who are D/HoH. PARTICIPANTS: Six hundred ninety-three athletes who are D/HoH and 1284 athletes who are hearing were included in this study. Athletes participated in collegiate athletics during the 2012 to 2013 through the 2016 to 2017 academic years. INTERVENTIONS: Concussion data were provided by the athletic training staff at each institution. MAIN OUTCOME MEASURES: Concussion counts, concussion rate, and injury rate ratios (IRRs) with 95% confidence intervals (95% CIs). RESULTS: Thirty athletes who are D/HoH and 104 athletes who are hearing suffered concussions. Athletes who are hearing had an increased injury rate compared with athletes who are D/HoH for all sports combined (IRR = 1.87, 95% CI, 1.26-2.78). Football athletes who are hearing also had an increased injury rate compared with football athletes who are D/HoH (IRR = 3.30, 95% CI, 1.71-6.37). Concussion rate was higher for male athletes who are hearing than male athletes who are D/HoH (IRR = 2.84, 95% CI, 1.62-4.97). No other significant differences regarding concussion risk were identified. CONCLUSIONS: Athletes who are D/HoH in sex-comparable sports may not have a higher rate of concussion than athletes who are hearing. Rate of concussion in football may be greater among athletes who are hearing compared with athletes who are D/HoH.

A Review of Workload-Monitoring Considerations for Baseball Pitchers.

Because of the unique demands of a pitch, baseball players have the greatest percentage of injuries resulting in surgery among high school athletes, with a majority of these injuries affecting the shoulder and elbow due to overuse from throwing. These injuries are believed to occur because of repeated microtrauma to soft tissues caused by the repetitive mechanical strain of throwing. Researchers and practitioners have suggested that baseball pitchers' workloads are a significant risk factor for injury in adolescent players, resulting in lost time and slowing of performance development. The purpose of our review was to investigate the current research relative to monitoring workload in baseball throwers and discuss techniques for managing and regulating cumulative stress on the arm, with a focus on preventing injury and optimizing performance in adolescent baseball pitchers.

Neural activity for hip-knee control in those with anterior cruciate ligament reconstruction: A task-based functional connectivity analysis.

Anterior cruciate ligament injury may induce neurophysiological changes for sensorimotor control. Neuroimaging investigations have revealed unique brain activity patterns for knee movement following injury, indicating potential neural mechanisms underlying aberrant neuromuscular control that may contribute to heightened risk of secondary injury, altered movement patterns and poor patient outcomes. However, neuroimaging paradigms thus far have been limited to single joint, single motion knee tasks. Therefore, we sought to overcome prior limitations to understand the effects of injury on neural control of lower extremity movement by employing a multi-joint motor paradigm and determining differences in neural activity between ACL-reconstructed (ACLr) individuals relative to healthy matched controls. Fifteen patients with left anterior cruciate ligament reconstruction and fifteen matched healthy controls participated in this study. Neural activity was examined using functional magnetic resonance imaging during a block-designed knee-hip movement paradigm (similar to a supine heel-slide). Participants for each group were monitored and task performance was controlled via a metronome to ensure the same spatial-temporal parameters. We observed that those with ACL reconstruction displayed increased activation within the intracalcarine cortex, lingual gyrus, occipital fusiform gyrus, lateral occipital cortex, angular gyrus, and superior parietal lobule relative to controls. A follow-up task-based functional connectivity analyses using seed regions identified from the group analysis revealed connectivity among fronto-insular-temporal and sensorimotor regions within the ACLr participants. The results of this fMRI investigation suggest ACLr individuals require increased activity and connectivity in areas responsible for visual-spatial cognition and orientation, and attention for hip and knee motor control.

Influence of a Multitask Paradigm on Motor and Cognitive Performance of Military and Law Enforcement Personnel: A Systematic Review.

PURPOSE: To review the current literature investigating if performance of tactical athletes under multitask paradigms is different than performance under single-task paradigms. METHODS: The authors completed a search of the literature published from January 01, 2000, to June 01, 2018, using key search terms in PubMed, Web of Science, SPORTDiscus, and Defense Technical Information Center (DTIC) databases. Studies that met inclusion and exclusion criteria were assessed for quality. RESULTS: Fourteen articles were identified as eligible to be included in the review. Compared with single-task, two studies reported better motor performance, six reported poorer motor performance, and three reported no difference in motor performance under multitask. Compared with single- task, two studies reported better cognitive performance, seven studies reported poorer cognitive performance, and three studies reported no difference in cognitive performance under multitask. CONCLUSION: As occupational duties become increasingly demanding, it is crucial to modify and adapt performance assessments to meet the needs required of tactical athletes to guide training and injury management programs. Motor and cognitive assessments are an integral part of performance evaluations to train, prepare, and rehabilitate tactical athletes. To meet the modern demands of tactical athletes, varying levels of difficulty in multitask paradigms that include both motor and cognitive tasks should be investigated to understand fundamental performance under operational settings to better translate across training paradigms and rehabilitation programs.