Professional American Football Players Research Articles

Characterizing Neurobehavioral Dysregulation Among Former American Football Players: Findings From the DIAGNOSE CTE Research Project.

Neurobehavioral dysregulation (NBD), a core clinical feature of traumatic encephalopathy syndrome, encompasses neuropsychiatric symptoms reported among individuals with a history of repetitive head impact exposure, including contact sport athletes. The objective of this study was to examine the construct and subconstructs of NBD through a series of factor and cluster analyses. Six clinician-scientists selected self-report questionnaire items relevant to NBD from seven available neuropsychiatric scales through a blinded voting process. These items were subjected to confirmatory factor analyses in a sample of 178 former college and professional American football players and 60 asymptomatic individuals without a history of repetitive head impact exposure. All participants were enrolled in the Diagnostics, Imaging, and Genetics Network for the Objective Study and Evaluation of Chronic Traumatic Encephalopathy Research Project. Factor scores were generated on the basis of the optimal expert-informed model for NBD. Construct validity was assessed with neuropsychiatric scales not included in generation of the factor scores. Cluster analyses with NBD factor scores were used to examine symptom profiles. Factor analyses confirmed that NBD was composed of four subconstructs: explosivity, emotional dyscontrol, impulsivity, and affective lability. Cluster analyses indicated four distinct symptom profiles of NBD in this group of former football players: asymptomatic (N=80, 45%), short fuse (N=33, 19%), high affective lability (N=34, 19%), and high NBD (N=31, 17%). These findings characterize NBD as a multifaceted clinical construct with a heterogeneous presentation, providing a foundation for empirical work on the diagnostic criteria for traumatic encephalopathy syndrome and research on the neurobiological underpinnings of NBD.

Age of First Exposure Does Not Relate to Post-Career Health in Former Professional American-Style Football Players

ObjectivePrior studies examining small samples of symptomatic former professional football players suggest that earlier age of first exposure (AFE) to American football is associated with adverse later life health outcomes. This study examined a larger, more representative sample of former professional American football players to assess associations between AFE before age 12 (AFE < 12) and clinical outcomes compared with those who started at age 12 or older (AFE 12 +).MethodsFormer professional American football players who completed a questionnaire were dichotomized into AFE < 12 and AFE 12 + . AFE groups were compared on outcomes including symptoms of depression and anxiety, perceived cognitive difficulties, neurobehavioral dysregulation, and self-reported health conditions (e.g., headaches, sleep apnea, hypertension, chronic pain, memory loss, dementia/Alzheimer’s disease, and others).ResultsAmong 4189 former professional football players (aged 52 ± 14 years, 39% self-reported as Black), univariable associations with negligible effect sizes were seen with AFE < 12, depressive symptoms (p = 0.03; η2 = 0.001), and anxiety-related symptoms (p = 0.02; η2 = 0.001) only. Multivariable models adjusting for age, race, body mass index, playing position, number of professional seasons, and past concussion burden revealed no significant relationships between AFE < 12 and any outcome. Linear and non-linear models examining AFE as a continuous variable showed similar null results.ConclusionsIn a large cohort of former professional American-style football players, AFE was not independently associated with adverse later life outcomes. These findings are inconsistent with smaller studies of former professional football players. Studies examining AFE in professional football players may have limited utility and generalizability regarding policy implications for youth sports.

Protein Requirements for Maximal Muscle Mass and Athletic Performance Are Achieved with Completely Plant-Based Diets Scaled to Meet Energy Needs: A Modeling Study in Professional American Football Players.

American football players consume large quantities of animal-sourced protein in adherence with traditional recommendations to maximize muscle development and athletic performance. This contrasts with dietary guidelines, which recommend reducing meat intake and increasing consumption of plant-based foods to promote health and reduce the risk of chronic disease. The capacity of completely plant-based diets to meet the nutritional needs of American football players has not been studied. This modeling study scaled dietary data from a large cohort following completely plant-based diets to meet the energy requirements of professional American football players to determine whether protein, leucine, and micronutrient needs for physical performance and health were met. The Cunningham equation was used to estimate calorie requirements. Nutrient intakes from the Adventist Health Study 2 were then scaled to this calorie level. Protein values ranged from 1.6-2.2 g/kg/day and leucine values ranged from 3.8-4.1 g/meal at each of four daily meals, therefore meeting and exceeding levels theorized to maximize muscle mass, muscle strength, and muscle protein synthesis, respectively. Plant-based diets scaled to meet the energy needs of professional American football players satisfied protein, leucine, and micronutrient requirements for muscle development and athletic performance. These findings suggest that completely plant-based diets could bridge the gap between dietary recommendations for chronic disease prevention and athletic performance in American football players.

Concussion burden and later-life cardiovascular risk factors in former professional American-style football players.

Mid-life cardiovascular risk factors are associated with later cognitive decline. Whether repetitive head injury among professional athletes impacts cardiovascular risk is unknown. We investigated associations between concussion burden and postcareer hypertension, high cholesterol, and diabetes among former professional American-style football (ASF) players. In a cross-sectional study of 4080 professional ASF players conducted between January 2015 and March 2022, we used an mulitsymptom concussion symptom score (CSS) and the number of loss-of-consciousness (LOC) episodes as a single severe symptom to quantify football-related concussion exposure. Primary outcomes were hypertension, dyslipidemia, and diabetes, defined by current or recommended prescription medication use. The prevalence of hypertension, high cholesterol, and diabetes among former players (52 ± 14 years of age) was 37%, 34%, and 9%. Concussion burden was significantly associated with hypertension (lowest vs. highest CSS quartile, odds ratio (OR) = 1.99; 95%CI: 1.33-2.98; p < 0.01) and high cholesterol (lowest vs. moderate CSS, OR = 1.46, 95%CI, 1.11-1.91; p < 0.01), but not diabetes. In fully adjusted models, the prevalence of multiple CVD was associated with CSS. These results were driven by younger former players (≤ 40 year of age) in which the odds of hypertension were over three times higher in those in the highest CSS quartile (OR = 3.29, 95%CI: 1.39-7.61; p = 0.01). Results were similar for LOC analyses. Prior concussion burden is associated with postcareer atherogenic cardiovascular risk profiles among former professional American football players.

Clinical Outcomes and Tau Pathology in Retired Football Players: Associations With Diagnosed and Witnessed Sleep Apnea.

Obstructive sleep apnea (SA) is common in older men and a contributor to negative cognitive, psychiatric, and brain health outcomes. Little is known about SA in those who played contact sports and are at increased risk of neurodegenerative disease(s) and other neuropathologies associated with repetitive head impacts (RHI). In this study, we investigated the frequency of diagnosed and witnessed SA and its contribution to clinical symptoms and tau pathology using PET imaging among male former college and former professional American football players. The sample included 120 former National Football League (NFL) players, 60 former college players, and 60 asymptomatic men without exposure to RHI (i.e., controls). Diagnosed SA was self-reported, and all participants completed the Mayo Sleep Questionnaire (MSQ, informant version), the Epworth Sleepiness Scale (ESS), neuropsychological testing, and tau (flortaucipir) PET imaging. Associations between sleep indices (diagnosed SA, MSQ items, and the ESS) and derived neuropsychological factor scores, self-reported depression (Beck Depression Inventory-II [BDI-II]), informant-reported neurobehavioral dysregulation (Behavior Rating Inventory of Executive Function-Adult Version [BRIEF-A] Behavioral Regulation Index [BRI]), and tau PET uptake, were tested. Approximately 36.7% of NFL players had diagnosed SA compared with 30% of the former college football players and 16.7% of the controls. Former NFL players and college football players also had higher ESS scores compared with the controls. Years of football play was not associated with any of the sleep metrics. Among the former NFL players, diagnosed SA was associated with worse Executive Function and Psychomotor Speed factor scores, greater BDI-II scores, and higher flortaucipir PET standard uptake value ratios, independent of age, race, body mass index, and APOE ε4 gene carrier status. Higher ESS scores correlated with higher BDI-II and BRIEF-A BRI scores. Continuous positive airway pressure use mitigated all of the abovementioned associations. Among the former college football players, witnessed apnea and higher ESS scores were associated with higher BRIEF-A BRI and BDI-II scores, respectively. No other associations were observed in this subgroup. Former elite American football players are at risk of SA. Our findings suggest that SA might contribute to cognitive, neuropsychiatric, and tau outcomes in this population. Like all neurodegenerative diseases, this study emphasizes the multifactorial contributions to negative brain health outcomes and the importance of sleep for optimal brain health.

Brain morphometry in former American football players: findings from the DIAGNOSE CTE research project.

Exposure to repetitive head impacts in contact sports is associated with neurodegenerative disorders including chronic traumatic encephalopathy (CTE), which currently can be diagnosed only at post-mortem. American football players are at higher risk of developing CTE given their exposure to repetitive head impacts. One promising approach for diagnosing CTE in vivo is to explore known neuropathological abnormalities at post-mortem in living individuals using structural MRI. MRI brain morphometry was evaluated in 170 male former American football players ages 45-74 years (n = 114 professional; n = 56 college) and 54 same-age unexposed asymptomatic male controls (n = 54, age range 45-74). Cortical thickness and volume of regions of interest were selected based on established CTE pathology findings and were assessed using FreeSurfer. Group differences and interactions with age and exposure factors were evaluated using a generalized least squares model. A separate logistic regression and independent multinomial model were performed to predict each traumatic encephalopathy syndrome (TES) diagnosis, core clinical features and provisional level of certainty for CTE pathology using brain regions of interest. Former college and professional American football players (combined) showed significant cortical thickness and/or volume reductions compared to unexposed asymptomatic controls in the hippocampus, amygdala, entorhinal cortex, parahippocampal gyrus, insula, temporal pole and superior frontal gyrus. Post hoc analyses identified group-level differences between former professional players and unexposed asymptomatic controls in the hippocampus, amygdala, entorhinal cortex, parahippocampal gyrus, insula and superior frontal gyrus. Former college players showed significant volume reductions in the hippocampus, amygdala and superior frontal gyrus compared to the unexposed asymptomatic controls. We did not observe Age × Group interactions for brain morphometric measures. Interactions between morphometry and exposure measures were limited to a single significant positive association between the age of first exposure to organized tackle football and right insular volume. We found no significant relationship between brain morphometric measures and the TES diagnosis core clinical features and provisional level of certainty for CTE pathology outcomes. These findings suggested that MRI morphometrics detect abnormalities in individuals with a history of repetitive head impact exposure that resemble the anatomic distribution of pathological findings from post-mortem CTE studies. The lack of findings associating MRI measures with exposure metrics (except for one significant relationship) or TES diagnosis and core clinical features suggested that brain morphometry must be complemented by other types of measures to characterize individuals with repetitive head impacts.

64 Neuroimaging Evidence of Neurodegenerative Disease in Former Professional American Football Players Who “Fail” Validity Testing: A Case Series

Objective:Former professional American football players have a high relative risk for neurodegenerative diseases like chronic traumatic encephalopathy (CTE). Interpreting low cognitive test scores in this population occasionally is complicated by performance on validity testing. Neuroimaging biomarkers may help inform whether a neurodegenerative disease is present in these situations. We report three cases of retired professional American football players who completed comprehensive neuropsychological testing, but “failed” performance validity tests, and underwent multimodal neuroimaging (structural MRI, Aß-PET, and tau-PET).Participants and Methods:Three cases were identified from the Focused Neuroimaging for the Neurodegenerative Disease Chronic Traumatic Encephalopathy (FIND-CTE) study, an ongoing multimodal imaging study of retired National Football League players with complaints of progressive cognitive decline conducted at Boston University and the UCSF Memory and Aging Center. Participants were relatively young (age range 55-65), had 16 or more years of education, and two identified as Black/African American. Raw neuropsychological test scores were converted to demographically-adjusted z-scores. Testing included standalone (Test of Memory Malingering; TOMM) and embedded (reliable digit span, RDS) performance validity measures. Validity cutoffs were TOMM Trial 2 &lt; 45 and RDS &lt; 7. Structural MRIs were interpreted by trained neurologists. Aß-PET with Florbetapir was used to quantify cortical Aß deposition as global Centiloids (0 = mean cortical signal for a young, cognitively normal, Aß negative individual in their 20s, 100 = mean cortical signal for a patient with mild-to-moderate Alzheimer’s disease dementia). Tau-PET was performed with MK-6240 and first quantified as standardized uptake value ratio (SUVR) map. The SUVR map was then converted to a w-score map representing signal intensity relative to a sample of demographically-matched healthy controls.Results:All performed in the average range on a word reading-based estimate of premorbid intellect. Contribution of Alzheimer’s disease pathology was ruled out in each case based on Centiloids quantifications &lt; 0. All cases scored below cutoff on TOMM Trial 2 (Case #1=43, Case #2=42, Case #3=19) and Case #3 also scored well below RDS cutoff (2). Each case had multiple cognitive scores below expectations (z &lt; -2.0) most consistently in memory, executive function, processing speed domains. For Case #1, MRI revealed mild atrophy in dorsal fronto-parietal and medial temporal lobe (MTL) regions and mild periventricular white matter disease. Tau-PET showed MTL tau burden modestly elevated relative to controls (regional w-score=0.59, 72nd%ile). For Case #2, MRI revealed cortical atrophy, mild hippocampal atrophy, and a microhemorrhage, with no evidence of meaningful tau-PET signal. For Case #3, MRI showed cortical atrophy and severe white matter disease, and tau-PET revealed significantly elevated MTL tau burden relative to controls (w-score=1.90, 97th%ile) as well as focal high signal in the dorsal frontal lobe (overall frontal region w-score=0.64, 74th%ile).Conclusions:Low scores on performance validity tests complicate the interpretation of the severity of cognitive deficits, but do not negate the presence of true cognitive impairment or an underlying neurodegenerative disease. In the rapidly developing era of biomarkers, neuroimaging tools can supplement neuropsychological testing to help inform whether cognitive or behavioral changes are related to a neurodegenerative disease.

2 The Longitudinal Relationship Between Concussion History, Years of Football Participation, and Alcohol Use Among Former National Football League (NFL) Players: an NFL-LONG Study

Objective:It has been posited that alcohol use may confound the association between greater concussion history and poorer neurobehavioral functioning. However, while greater alcohol use is positively correlated with neurobehavioral difficulties, the association between alcohol use and concussion history is not well understood. Therefore, this study investigated the cross-sectional and longitudinal associations between cumulative concussion history, years of contact sport participation, and health-related/psychological factors with alcohol use in former professional football players across multiple decades.Participants and Methods:Former professional American football players completed general health questionnaires in 2001 and 2019, including demographic information, football history, concussion/medical history, and health-related/psychological functioning. Alcohol use frequency and amount was reported for three timepoints: during professional career (collected retrospectively in 2001), 2001, and 2019. During professional career and 2001 alcohol use frequency included none, 1-2, 3-4, 5-7 days/week, while amount included none, 12, 3-5, 6-7, 8+ drinks/occasion. For 2019, frequency included never, monthly or less, 2-4 times/month, 2-3 times/week, &gt;4 times/week, while amount included none, 1-2, 3-4, 5-6, 7-9, 10+ drinks/occasion. Scores on a screening measure for Alcohol Use Disorder (CAGE) were also available at during professional career and 2001 timepoints. Concussion history was recorded in 2001 and binned into five groups: 0, 1-2, 3-5, 6-9, 10+. Depression and pain interference were assessed via PROMIS measures at all timepoints. Sleep disturbance was assessed in 2001 via separate instrument and with PROMIS Sleep Disturbance in 2019. Spearman’s rho correlations tested associations between concussion history and years of sport participation with alcohol use across timepoints, and whether poor health functioning (depression, pain interference, sleep disturbance) in 2001 and 2019 were associated with alcohol use both within and between timepoints.Results:Among the 351 participants (Mage=47.86[SD=10.18] in 2001), there were no significant associations between concussion history or years of contact sport participation with CAGE scores or alcohol use frequency/amount during professional career, 2001, or 2019 (rhos=-.072-.067, ps&gt;.05). In 2001, greater depressive symptomology and sleep disturbance were related to higher CAGE scores (rho=.209, p&lt;.001; rho=.176, p&lt;.001, respectively), while greater depressive symptomology, pain interference, and sleep disturbance were related to higher alcohol use frequency (rho=.176, p=.002; rho=.109, p=.045; rho=.132, p=.013, respectively) and amount/occasion (rho=.215, p&lt;.001; rho=.127, p=.020; rho=.153, p=.004, respectively). In 2019, depressive symptomology, pain interference, and sleep disturbance were not related to alcohol use (rhos=-.047-.087, ps&gt;.05). Between timepoints, more sleep disturbance in 2001 was associated with higher alcohol amount/occasion in 2019 (rho=.115, p=.036).Conclusions:Increased alcohol intake has been theorized to be a consequence of greater concussion history, and as such, thought to confound associations between concussion history and neurobehavioral function later in life. Our findings indicate concussion history and years of contact sport participation were not significantly associated with alcohol use cross-sectionally or longitudinally, regardless of alcohol use characterization. While higher levels of depression, pain interference, and sleep disturbance in 2001 were related to greater alcohol use in 2001, they were not associated cross-sectionally in 2019. Results support the need to concurrently address health-related and psychological factors in the implementation of alcohol use interventions for former NFL players, particularly earlier in the sport discontinuation timeline.

The association between playing professional American football and longevity.

Recent research concludes that professional American football players (hereafter, "football players") live longer than American men in general, despite experiencing higher rates of chronic traumatic encephalopathy (CTE) and cardiovascular disease (CVD). This suggests that the longevity-enhancing benefits of playing football (e.g., physical fitness, money) outweigh the costs associated with CTE, CVD, and other longevity detriments of playing football. However, these surprising results may be the consequence of flawed research design. To investigate, we conducted two analyses. In analysis 1, we compared a) all professional American football players whose first season was 1986 or between 1988 and 1995 to b) a random sample of same-age American men observed as part of the National Health Interview Surveys in those same years selected on good health, at least 3 y of college, and not being poor. The exposure consists of playing one or more games of professional football; the outcome is risk of death within 25 y. In analysis 2, we use data on 1,365 men drafted to play in the (American) National Football League in the 1950s-906 of whom ultimately played professional football, and 459 of whom never played a game in any professional league. We estimate the association between playing football and survival through early 2023. In both analyses, we investigate differences between linemen and other position players. In contrast to most prior research, in both analyses, we find that linemen died earlier than otherwise similar men; men who played other positions died no earlier (or later).

Interaction of Medical Conditions and Football Exposures Associated with Premortem Chronic Traumatic Encephalopathy Diagnosis in Former Professional American Football Players.

Despite being a postmortem diagnosis, former professional American-style football players report receiving chronic traumatic encephalopathy (CTE) diagnoses from medical care providers. However, many players also report other health conditions that manifest with cognitive and psychological symptoms. The purpose of this study was to identify how medical conditions, psychological disorders, and football exposure combinations are associated with former athletes reporting a premortem CTE diagnosis. This study was a cross-sectional cohort survey from 2015 to 2019 of 4033 former professional American-style football players. Demographics (age, race, domestic status, primary care recipient), football-related factors (position, years of professional play, burden of symptoms following head impacts, performance-enhancing drug use), and comorbidities (sleep apnea, psychological disorder status [depression and anxiety; either depression or anxiety; neither depression nor anxiety], diabetes mellitus, attention-deficit/hyperactivity disorder, hypertension, heart conditions, high cholesterol, stroke, cancer, low testosterone, chronic pain, current and maximum body mass index) were recorded. A Chi-square automatic interaction detection (CHAID) decision tree model identified interactive effects between demographics, health conditions, and football exposures on the CTE diagnosis. Depression showed the strongest univariate association with premortem CTE diagnoses (odds ratio [OR] = 9.5, 95% confidence interval [CI] 6.0-15.3). CHAID differentiated participants with premortem CTE diagnoses with 98.2% accuracy and area under the curve = 0.81. Participants reporting both depression and anxiety were more likely to have a CTE diagnosis compared with participants who reported no psychological disorders (OR = 12.2; 95% CI 7.3-21.1) or one psychological disorder (OR = 4.5; 95% CI 1.9-13.0). Sleep apnea was also associated with a CTE diagnosis amongst those with both depression and anxiety (OR = 2.7; 95% CI 1.4-5.2). Clinical phenotypes including psychological disorders and sleep apnea were strongly associated with an increased likelihood of having received a pre-mortem CTE diagnosis in former professional football players. Depression, anxiety, and sleep apnea produce cognitive symptoms, are treatable conditions, and should be distinguished from neurodegenerative disease.

Subjective and Performance-Based Cognition and Their Associations with Head Injury History in Older Former National Football League Players.

Investigate the association between self-reported subjective and performance-based cognition among older (50-70 years) former professional American football players, as well as the relationship of cognitive measures with concussion history and years of football participation, as a proxy for repetitive head impact exposure. Among older former National Football League (NFL) players ( N = 172; mean age = 60.69 ± 5.64), associations of subjective (Patient Reported Outcome Measurement Information System Cognitive Function-Short Form) and performance-based cognitive measures (Brief Test of Adult Cognition by Telephone [BTACT] Executive Function and Episodic Memory indices) were assessed via univariable and multivariable regression models, with a priori covariates of depression and race. A similar univariate and multivariable regression approach assessed associations between concussion history and years of football participation with subjective and performance-based cognitive measures. In a sample subset ( n = 114), stability of subjective cognitive rating was assessed via partial correlation. Subjective ratings of cognition were significantly associated with performance-based assessment, with moderate effect sizes (episodic memory ηp2 = 0.12; executive function ηp2 = 0.178). These associations were weakened, but remained significant ( P s < 0.05), with the inclusion of covariates. Greater concussion history was associated with lower subjective cognitive function ( ηp2 = 0.114, P < 0.001), but not performance-based cognition. The strength of association between concussion history and subjective cognition was substantially weakened with inclusion of covariates ( ηp2 = 0.057). Years of participation were not associated with measures of subjective or objective cognition ( P s > 0.05). These findings reinforce the importance of comprehensive evaluation reflecting both subjective and objective measures of cognition, as well as the consideration of patient-specific factors, as part of a comprehensive neurobehavioral and health assessment of older former contact sport athletes.

MRI Findings Associated With Anterior Cruciate Ligament Tears in National Football League Athletes.

Anterior cruciate ligament (ACL) tears are a high-frequency injury requiring a lengthy recovery in professional American football players. Concomitant pathology associated with ACL tears as identified on magnetic resonance imaging (MRI) is not well understood in these athletes. To describe the MRI findings of concomitant injuries associated with ACL tears among athletes in the National Football League (NFL). Cross-sectional study; Level of evidence, 3. Of 314 ACL injuries in NFL athletes from 2015 through 2019, 191 complete MRI scans from the time of primary ACL injury were identified and reviewed by 2 fellowship-trained musculoskeletal radiologists. Data were collected on ACL tear type and location, as well as presence and location of bone bruises, meniscal tears, articular cartilage pathology, and concomitant ligament pathology. Mechanism data from video review were linked with imaging data to assess association between injury mechanism (contact vs noncontact) and presence of concomitant pathology. Bone bruises were evident in 94.8% of ACL tears in this cohort, most often in the lateral tibial plateau (81%). Meniscal, additional ligamentous, and/or cartilage injury was present in 89% of these knees. Meniscal tears were present in 70% of knees, lateral (59%) more than medial (41%). Additional ligamentous injury was present in 71% of all MRI scans, more often a grade 1/2 sprain (67%) rather than a grade 3 tear (33%), and most often involving the medial collateral ligament (MCL) (57%) and least often the posterior cruciate ligament (10%). Chondral damage was evident in 49% of all MRI scans, with ≥1 full-thickness defect in 25% of all MRI scans, most often lateral. Most (79%) ACL tears did not involve direct contact to the injured lower extremity. Direct contact injuries (21%) were more likely to have a concomitant MCL tear and/or medial patellofemoral ligament injury and less likely to have a medial meniscal tear. ACL tears were rarely isolated injuries in this cohort of professional American football athletes. Bone bruises were almost always present, and additional meniscal, ligamentous, and chondral injuries were also common. MRI findings varied by injury mechanism.

Athlete activism and attendance behavior in the National Football League

ABSTRACT Research Question There is a growing body of research focused on athlete activism and social movements in the sport literature. One lineage of research examined consumer perceptions and reactions to these movements. Such discussions, however, generally concentrate on detecting changes in consumer behaviors rather than understanding the nuance in those changing behaviors. The present study advances the literature by considering how two potential factors – the size of protests and the geographic proximity consumers have to a protest – impact attendance at NFL games. Research Methods The present study utilizes social protests carried out by professional American football players in 2016–2017 to measure the number of workers who participated in the protests. Specifically, estimations of Tobit and fixed-effects regressions from 1003 games examine whether protests conducted by NFL players impact attendance in local markets. Results and Findings Findings from all estimated models suggest that as the number of players who participated in the protests increased, there was a decline in NFL attendance. Moreover, consumers were sensitive only to protests occurring within their own local market, indicating consumers tended to react to protests for teams located in the same city. Implications Scholars argue that for social movements to be successful in disrupting organizations, many participants are needed. In response to this point, the present research extends the research in sport-based social movements by developing further understanding of how they impact consumer behaviors, and thus affect the management of sport organizations.

Automated Detection of Cognitive Performance and Resilience Changes in Former Professional American Football Players Following the Administration of a Hemp Extract

Automated Detection of Cognitive Performance and Resilience Changes in Former Professional American Football Players Following the Administration of a Hemp Extract

An interdisciplinary computational model for predicting traumatic brain injury: Linking biomechanics and functional neural networks

The brain is a complex network consisting of neuron cell bodies in the gray matter and their axonal projections, forming the white matter tracts. These neurons are supported by an equally complex vascular network as well as glial cells. Traumatic brain injury (TBI) can lead to the disruption of the structural and functional brain networks due to disruption of both neuronal cell bodies in the gray matter as well as their projections and supporting cells. To explore how an impact can alter the function of brain networks, we integrated a finite element (FE) brain mechanics model with linked models of brain dynamics (Kuramoto oscillator) and vascular perfusion (Balloon-Windkessel) in this study. We used empirical resting-state functional magnetic resonance imaging (MRI) data to optimize the fit of our brain dynamics and perfusion models to clinical data. Results from the FE model were used to mimic injury in these optimized brain dynamics models: injury to the nodes (gray matter) led to a decrease in the nodal oscillation frequency, while damage to the edges (axonal connections/white matter) progressively decreased coupling among connected nodes. A total of 53 cases, including 33 non-injurious and 20 concussive head impacts experienced by professional American football players were simulated using this integrated model. We examined the correlation of injury outcomes with global measures of structural connectivity, neural dynamics, and functional connectivity of the brain networks when using different lesion methods. Results show that injurious head impacts cause significant alterations in global network topology regardless of lesion methods. Changes between the disrupted and healthy functional connectivity (measured by Pearson correlation) consistently correlated well with injury outcomes (AUC≥0.75), although the predictive performance is not significantly different (p>0.05) to that of traditional kinematic measures (angular acceleration). Intriguingly, our lesion model for gray matter damage predicted increases in global efficiency and clustering coefficient with increases in injury risk, while disrupting axonal connections led to lower network efficiency and clustering. When both injury mechanisms were combined into a single injury prediction model, the injury prediction performance depended on the thresholds used to determine neurodegeneration and mechanical tolerance for axonal injury. Together, these results point towards complex effects of mechanical trauma to the brain and provide a new framework for understanding brain injury at a causal mechanistic level and developing more effective diagnostic methods and therapeutic interventions.

There Is Crying in Football: Reactions to an Athlete’s Weeping

The current study hypothesized that the status of a professional American football player would influence how observers perceived his weeping after losing a game. It was also predicted that the importance of the game (the NFL Super Bowl vs. a regular season game) would influence perceptions of his tears. Two hundred twenty-two adults, recruited nationally, read 1 of 4 vignettes in a 2 (player status: high- or low-performing) x 2 (game status: Super Bowl or regular season game) between-subjects design. The vignette describes a close game that is ultimately lost by the target’s team, with the target weeping at its conclusion. Participants (N = 213) rated his postgame weeping as more appropriate and justifiable, using an allowance composite score, as it was found that there was a significant difference for both player, F(2, 196) = 10.13, p &lt; .001; Wilks’ Lambda= .91; η2 = .09, and game, F(2, 196) = 4.27, p = .02; Wilks’ Lambda = .96; η2 = .04, status. There were also significant differences found in analyses for player status on perceived emotional stability, F(1, 202) = 20.22, p &lt; .001, η2 = .09, and game status on perceived competency, F(1, 200) = 173.63, p &lt; .001, η2 = .47. The ramifications of these findings, that situational details and personal attributes of the target influence observers’ judgments of emotional appropriateness, are discussed.

Epidemiology of Traumatic Posterior Hip Instability in the National Football League.

Background:There is a paucity of literature regarding injury incidence, mechanism, and return to play in National Football League (NFL) players who have sustained traumatic posterior hip instability.Purpose:To describe the incidence of traumatic posterior hip instability and the rate of return to play in NFL players across 18 seasons.Study Design:Descriptive epidemiology study.Methods:We retrospectively assessed all traumatic posterior hip dislocations/subluxations that occurred during football-related activities in the NFL seasons from 2000 through 2017. Player demographics and injury data (injury mechanism, season of injury, treatment, days missed, and return to play time) were collected from all 32 NFL teams prospectively through a leaguewide electronic health record system. Descriptive statistics are presented.Results:Across the 18 NFL seasons, 16 posterior hip instability injuries in 14 players were reported, with a maximum incidence of 4 (25%) in 2013. Posterior hip instability was predominantly sustained by offensive players (64.3%), with tight ends being the most affected (31.3%). Half of the injuries occurred during the regular season, 43.8% in the preseason, and 6.2% in the offseason. Of all injuries, 37.5% were noncontact, while 56.3% involved contact (direct or indirect), and 6.2% were of unknown mechanism. Among noncontact injuries, 66.7% occurred during cutting and change of direction while sprinting. The time of return to full participation was documented for 11 of the 16 reported injuries (68.8%); among them, the mean time loss was 136.7 ± 83.8 days—143.3 ± 99.6 days if the player underwent surgery (n = 4) and 116.7 ± 76.2 days missed by players without surgery (n = 6)—the treatment modality was unknown in 1 player.Conclusion:Although the incidence of traumatic posterior hip instability during the study period was low, all injured athletes missed time from football activities and competitions. Injuries that required surgery led to more missed time than those that did not. Ongoing research to understand risk factors and mechanisms of this injury, in conjunction with improvements to prevention and rehabilitation protocols, is necessary to ensure the safety of professional American football players.

Neuropsychological test performance in former college and professional American football players

AbstractBackgroundRepetitive head impacts from American football have been associated with long‐term cognitive symptoms. The late neuropsychological profiles of this population is not well‐characterized. Research has relied on retrospective informant reports and/or has been small samples of former professional players. We describe objective neuropsychological test performance in former college and professional American football players.MethodsMale (45‐74 years) former National Football League (n=107) and college football players (n=59) from the DIAGNOSE‐CTE Research Project completed a neuropsychological test battery, Functional Activities Questionnaire (FAQ) and Quick Dementia Rating Scale (QDRS). Neuropsychological test scores were converted to T‐scores using age, sex, and/or education‐adjusted normative data. T‐scores&lt;35 defined impairment. Participants were enrolled across the spectrum of symptom severity (asymptomatic to dementia). Individuals without decisional capacity were excluded. Participants with missing data (n=4) and who scored &lt;45 on Test of Memory Malingering Trial 2 (n=10) were excluded.Results108 (65.1%) identified as White and 53 (31.9%) as Black. Mean education years was 16.76 (SD=1.48). Fourteen (8.4%) and 6 (3.6%) reported diagnostic history of ADHD and learning disability, respectively. Average Montreal Cognitive Assessment score was 24.96 (SD=3.17); 85 (51.2%) scored &lt;26. Impairment rates were highest for learning and episodic memory. On Neuropsychological Assessment Battery List Learning, 29.5% were impaired on Immediate recall, 36.1% on Short Delay, and 44.0% on Long Delay Recall. Impairment rates for Craft Story Immediate and Delayed Recall (Paraphrase) were 15.7% and 18.7%, respectively. 19.9% and 15.7% were impaired on learning and delayed recall of the Brief Visuospatial Memory Test‐Revised. Impairments were frequent on the Multilingual Naming Test (20.5%), Trail Making Test Parts B (19.3%) and A (18.1%), Animal Fluency (15.7%), and Number Span Backward (15.1%). Impairments were less common (&lt;10%) for phonemic fluency, planning, basic attention, and visual‐perceptual abilities, Mean FAQ was 3.11 (SD=5.14); 23 (13.9%) had an FAQ &gt;9. Based on QDRS scores, 66 (39.8%) had mild cognitive impairment, 44 (26.5%) mild dementia, and 6 (3.6%) moderate dementia.ConclusionsIn these former American football players, neuropsychological impairments were most frequent in episodic memory, followed by confrontation naming and executive function. Further research is needed to delineate this population’s unique neuropsychological profile.

Long‐term effects of repetitive head impacts on gray matter cortical thickness

AbstractBackgroundRepetitive head impact (RHI) exposure has been associated with the neurodegenerative disease chronic traumatic encephalopathy (CTE). Magnetic resonance imaging (MRI) and postmortem research suggest frontotemporal atrophy may be characteristic of CTE. The late effects of RHI on cortical volume remain poorly understood due to focus on male former professional American football players and lack of examination of specific lobar gyri. We leveraged the Boston University Alzheimer’s Disease Research Center (BU ADRC) to compare frontal, temporal, and parietal gyri gray matter thickness between participants with and without RHI exposure.Method39 participants exposed to RHI and 33 similar‐aged (+/‐ 5 years) participants without RHI from the BU ADRC, all spanning the cognitive continuum, underwent MRI on a 3T Philips. Freesurfer was used to derive regional gray matter cortical thickness values. For the frontal, temporal, and parietal lobes, we computed mean composites of superior, middle, and inferior gyri gray matter measures. Analysis of covariance compared participants with and without RHI, controlling for age, sex, race, education and hippocampal volume.ResultMean age was 62.31 (SD=8.87), 34 (47.2%) were female, and 65 (90.3%) were White. Of the RHI group, 23 (59.0%) played American football, 9 (23.1%) ice hockey, 5 (12.8%) were boxers, and 3 (7.7%) were amateur wrestlers. Compared to non‐RHI, RHI‐exposed participants had decreased gray matter thickness of superior (marginal mean diff [MD]=0.10, p&lt;0.01) and middle frontal gyri (MD=0.06, p=0.03), and the middle temporal gyrus (MD=0.07, p=0.03). There were no differences in gray matter thickness for inferior frontal, superior or inferior temporal, or parietal gyri. Because the CTE tau lesion is uniquely at the sulcal depths, we examined the gray matter thickness of the banks of superior temporal sulcus and RHI participants had reduced thickness (MD=0.09, p=0.02).ConclusionFrontotemporal atrophy may be a characteristic late effect of RHI exposure. Further examination of thickness of different lobar gyri in the setting of RHI may facilitate disease differentiation. Larger samples will be important to examine how the effects of RHI on gray matter cortical thickness differ by sex, sport played, etc.

Sleep disruption and disorders in former college and professional American football players

AbstractBackgroundLittle is known about sleep in those with a history of contact sports, who are at increased risk for neurodegenerative disease(s). Sleep disruption and disorders are increasingly recognized as having a bidirectional relationship with Alzheimer’s disease neuropathology. Here, we investigated self‐reported sleep disruption and disorders in male former college and professional American football players.Method116 former National Football League (NFL) players, 60 former college football players, and 60 asymptomatic men without a history of traumatic brain injury or repetitive head impacts (controls), all between 45‐74 years, completed the Mayo Sleep Questionnaire (MSQ) which includes the Epworth Sleepiness Scale (ESS). Former American football players were enrolled across the spectrum of symptom severity (asymptomatic to mild dementia). Using binary logistic regression or analysis of covariance, comparisons (controlling for age, racial identity, body mass index, APOE e4 status) on each of the MSQ items and the ESS were made between each of the study groups.ResultCompared to controls, former NFL players were more likely to restless legs (OR = 7.32, 95% CI = 1.63‐32.97*), sleepwalking (OR = 8.65, 95% CI = 1.08‐69.22*), observed apnea (OR = 2.25, 95% CI = 1.04‐4.85*), lower alertness levels (marginal mean diff. = 0.90**) and had higher ESS (marginal mean diff. = 2.37**). Former college football players reported greater sleep disturbances compared with controls: restless legs (OR = 10.82, 95% CI = 1.86‐62.89**), sleepwalking (OR = 10.45, 95% CI = 1.12‐97.58*), alertness levels (marginal mean diff. = 1.48**) and ESS (marginal mean diff. = 2.76*). There were no college vs control differences for observed apnea. There were no differences between former NFL players and former college football players on any sleep metric. **p&lt;.005, *p&lt;.05.ConclusionSleep disturbances may be an important factor to investigate in those with a history of participation in American football.