American Football Research Articles

Chronic traumatic encephalopathy in athletes, players, boxers and military: systematic review

The objective of the study was to demonstrate whether athletes, players, boxers and military personnel can really be victims of CTE, and to elucidate this pathology. In 53 articles, 14 were selected for qualitative synthesis in the results table that addresses CTE in football, soccer and rugby players, boxers and the military. Neuropathologically, CTE shows cerebral atrophy, a pelvic septum cavity with fenestrations, dense diffuse immunoreactive inclusions and a TDP-43 proteinopathy. Microscopically, there are extensive neurofibrillary tangles and spindle-shaped neurites throughout the brain. Thus, CTE is characterized by being a distinct tauopathy and with a clear environmental etiology. American football players, boxers and the military are more likely to trigger CET, due to the constant mechanical shocks from their heads. The most frequent clinical manifestations were: headache, aggressiveness, dementia, executive dysfunction and suicide. CET is definitely diagnosed only at autopsy, there is no specific treatment for it, but support and safety measures can help the patient. Advances to definitively diagnose CTE in living people and specific treatment for this disease are needed.

Career duration and later-life health conditions among former professional American-style football players

ObjectivesCareer duration is often used as a metric of neurotrauma exposure in studies of elite athletes. However, as a proxy metric, career length may not accurately represent causal factors, and...

Optimizing Football Formation Analysis via LSTM-Based Event Detection

The process of manually annotating sports footage is a demanding one. In American football alone, coaches spend thousands of hours reviewing and analyzing videos each season. We aim to automate this process by developing a system that generates comprehensive statistical reports from full-length football game videos. Having previously demonstrated the proof of concept for our system, here, we present optimizations to our preprocessing techniques along with an inventive method for multi-person event detection in sports videos. Employing a long short-term memory (LSTM)-based architecture to detect the snap in American football, we achieve an outstanding LSI (Levenshtein similarity index) of 0.9445, suggesting a normalized difference of less than 0.06 between predictions and ground truth labels. We also illustrate the utility of snap detection as a means of identifying the offensive players’ assuming of formation. Our results exhibit not only the success of our unique approach and underlying optimizations but also the potential for continued robustness as we pursue the development of our remaining system components.

On-field concurrent validity of flight time-based countermovement jump height during fatigue: A comparison between inertial measurement units worn at different locations on the body

ABSTRACT We explored the feasibility of utilizing immediate changes in flight time-based vertical countermovement jump height as an on-field measure for fatigue-induced decrements in performance. Comparing Inertial Measurement Units (IMUs) worn at five body locations (feet, shorts for thighs and pelvis, waist strap, and thorax in a standard GPS vest) with a force plate as a reference, we enlisted 19 amateur football players who performed a series of 10 maximal 30 m sprints (initiated every minute). Maximal jumps were executed immediately before and after each sprint, with the latter jumps recorded on a force plate integrated into the field. Bland Altman’s bias (−0.49 cm) and limits of agreement (1.01 cm) were minimal for the feet IMUs. The thorax IMU had the highest bias (−6.35 cm), but the limits of agreement (2.73 cm) were similar to the other locations. Repeated measures correlations (rmcorr) between force plate and IMUs were excellent for the feet (rmcorr = 0.98) and good for the thorax (rmcorr = 0.86) and other locations except for the waist strap. In the fatigued state, within-session coefficients of variation ranged from 4.0% (pelvis in shorts) to 6.5% (waist strap). These findings suggest that body-worn IMUs possess the potential for a prompt and straightforward on-field vertical jump assessment to monitor acute fatigue.

Assessment of Blood Pressure Levels and Left Ventricular Functions of American Football Players in Türkiye

Assessment of Blood Pressure Levels and Left Ventricular Functions of American Football Players in Türkiye

Assessment of Eating Disorder Risk According to Sport Level, Sex, and Social Media Use among Polish Football Players: A Cross-Sectional Study

Background/Objectives: Eating disorders (EDs) pose a significant health issue affecting athletes, with risk factors varying by sport level, sex, and social media use. This study assesses the risk of EDs among professional and amateur football players, considering these factors, and compares findings with a control group of non-athletes. Methods: The study involved 170 participants, including non-athletes as a control group, categorized by sex and sport level. The mean age of participants was 24.3 ± 4.20, with an age range of 18–36. The Eating Attitudes Test (EAT-26) and body mass index (BMI) assessments were used to determine ED risk. Results: Results showed a higher prevalence of ED risk among professional athletes, especially women, compared to amateurs and non-athletes. Social media use and body comparisons were linked to increased ED risk, with professional athletes exhibiting higher vulnerability due to performance pressures. Women, particularly those in professional sports, showed a higher risk of EDs than men, influenced by social and aesthetic pressures. Conclusions: The findings highlight the need for targeted interventions, promoting healthier body image perceptions and addressing social media’s role in shaping body dissatisfaction. Psychological support and sex-specific strategies should be integrated into athlete care programs to mitigate these risks.

An Effective Method of Aerobic Capacity Development: Combined Training with Maximal Aerobic Speed and Small-Sided Games for Amateur Football Players

This study aimed to investigate the effects of combined training with maximal aerobic speed and small-sided games on football players’ aerobic capacity development. Methods: The football players were divided into three groups as a combined training group (n = 20) (Mean ± SD age 23.40 ± 2.92 yrs, BMI was 23.67 ± 1.59 kg/m2, mass: 74.80 ± 5.46 kg, height: 177.73 ± 4.31 cm), maximal aerobic speed group (n = 20) (Mean ± SD age 23.93 ± 2.46 yrs, BMI was 23.32 ± 1.42 kg/m2, mass: 72.66 ± 5.38 kg, height: 176.46 ± 4.99 cm) and regular training group (n = 20) (Mean ± SD age 24.80 ± 5.84 yrs, BMI was 22.87 ± 1.67 kg/m2, mass: 73.06 ± 6.74 kg, height: 178.33 ± 7.98 cm). In addition to regular football training, maximal aerobic speed training with small-sided games was applied to the combined training group (CT) and only maximal aerobic speed training was applied to the maximal aerobic speed group (MAS) twice a week for 12 weeks. The normal training group (NT) continued their routine football training programme. All participants applied the Yo-Yo IR1 test in the pre-test and post-test of the study. As a result of normality tests, it was determined that the data showed normal distribution, and the ANOVA test and Tukey’s multiple comparison test were used in the intergroup evaluation. Results: When the Yo-Yo IR1 Test pre-test and post-test results were analysed, maximal aerobic speed training with small-sided games (CT) and maximal aerobic speed (MAS) groups were significantly higher compared to the normal training (NT) group regarding training load, running distance, and VO2max value among the football players (p = 0.001). There was no difference in the normal training group (p > 0.05). As a result, it was determined that combined training with maximal aerobic speed, small-sided games, and only maximal aerobic speed effectively improved football players’ aerobic capacity and general performance.

Understanding beliefs and perceptions of parents, coaches, and organizational leaders toward non-concussive head impact exposure in youth American football

Understanding beliefs and perceptions of parents, coaches, and organizational leaders toward non-concussive head impact exposure in youth American football

OS EFEITOS DA SUPLEMENTAÇÃO DE CREATINA NO DESEMPENHO DOS ATLETAS: UMA REVISÃO DE LITERATURA

Creatine is a highly popular dietary supplement among athletes due to its ergogenic potential. In view of this, this study aims to verify in the specialized literature the main effects of creatine supplementation on athlete performance. The methodology used comprised a narrative literature review, with 12 scientific articles selected from the period 2017 to 2024 in the following databases: PubMed, Medline, Scielo and Lilacs. The results demonstrate that creatine supplementation produces ergogenic effects, positively impacting athletes' muscle strength, endurance and power, reducing the incidence of cramps and injuries, especially in American football, soccer, basketball, tennis and handball. Thus, it is concluded that this supplementation promotes significant improvements in muscle performance and body composition during athletes' periodized training, involving the repetition of high-intensity exercises in short, medium and prolonged periods.

Sensitivity And Agreement Between Head Impact Monitoring Devices In American Football

Sensitivity And Agreement Between Head Impact Monitoring Devices In American Football

Fatigue Index Isn’t Related To Exercising Microvascular Oxygenation During Repeated Sprinting In Collegiate American Football

Fatigue Index Isn’t Related To Exercising Microvascular Oxygenation During Repeated Sprinting In Collegiate American Football

Cavum Septum Pellucidum in Former American Football Players: Findings From the DIAGNOSE CTE Research Project.

Exposure to repetitive head impacts (RHI) is linked to the development of chronic traumatic encephalopathy (CTE), which can only be diagnosed at post-mortem. The presence of a cavum septum pellucidum (CSP) is a common finding in post-mortem studies of confirmed CTE and in neuroimaging studies of individuals exposed to RHI. This study examines CSP in living former American football players, investigating its association with RHI exposure, traumatic encephalopathy syndrome (TES) diagnosis, and provisional levels of certainty for CTE pathology. Data from the DIAGNOSE CTE Research Project were used to compare the presence and ratio of CSP in former American football players (n = 175), consisting of former college (n = 58) and former professional players (n = 117), and asymptomatic unexposed controls without RHI exposure (n = 55). We further evaluated potential associations between CSP measures and cumulative head impact index (CHII) measures (frequency, linear acceleration, and rotational force), a TES diagnosis (yes/no), and a provisional level of certainty for CTE pathology (suggestive, possible, and probable). Former American football players exhibited a higher CSP presence and ratio than unexposed asymptomatic controls. Among player subgroups, professional players showed a greater CSP ratio than former college players and unexposed asymptomatic controls. Among all football players, CHII rotational forces correlated with an increased CSP ratio. No significant associations were found between CSP measures and diagnosis of TES or provisional levels of certainty for CTE pathology. This study confirms previous findings, highlighting a greater prevalence of CSP and a greater CSP ratio in former American football players compared with unexposed asymptomatic controls. In addition, former professional players showed a greater CSP ratio than college players. Moreover, the relationship between estimates of CHII rotational forces and CSP measures suggests that cumulative frequency and strength of rotational forces experienced in football are associated with CSP. However, CSP does not directly correlate with TES diagnosis or provisional levels of certainty for CTE, indicating that it may be a consequence of RHI associated with rotational forces. Further research, especially longitudinal studies, is needed for confirmation and to explore changes over time.

Examination of plasma biomarkers of amyloid, tau, neurodegeneration, and neuroinflammation in former elite American football players.

Blood-based biomarkers offer a promising approach for the detection of neuropathologies from repetitive head impacts (RHI). We evaluated plasma biomarkers of amyloid, tau, neurodegeneration, and inflammation in former football players. The sample included 180 former football players and 60 asymptomatic, unexposed male participants (aged 45-74). Plasma assays were conducted for beta-amyloid (Aβ) 40, Aβ42, hyper-phosphorylated tau (p-tau) 181+231, total tau (t-tau), neurofilament light (NfL), glial fibrillary acidic protein (GFAP), interleukin-6 (IL-6), Aβ42/p-tau181 and Aβ42/Aβ40 ratios. We evaluated their ability to differentiate the groups and associations with RHI proxies and traumatic encephalopathy syndrome (TES). P-tau181 and p-tau231(padj=0.016) were higher and Aβ42/p-tau181 was lower(padj=0.004) in football players compared to controls. Discrimination accuracy for p-tau was modest (area under the curve [AUC]=0.742). Effects were not attributable to AD-related pathology. Younger age of first exposure (AFE) correlated with higher NfL (padj=0.03) and GFAP (padj=0.033). Plasma GFAP was higher in TES-chronic traumatic encephalopathy (TES-CTE) Possible/Probable (padj=0.008). Plasma p-tau181 and p-tau231, GFAP, and NfL may offer some usefulness for the characterization of RHI-related neuropathologies. Former football players had higher plasma p-tau181 and p-tau231 and lower Aβ42/ptau-181 compared to asymptomatic, unexposed men. Younger age of first exposure was associated with increased plasma NfL and GFAP in older but not younger participants. Plasma GFAP was higher in participants with TES-CTE possible/probable compared to TES-CTE no/suggestive.

Knee

The October 2024 Knee Roundup360 looks at: Managing the unexpected: treatment of intraoperative medial collateral ligament injuries; Identifying subgroups of patients that may benefit from robotic arm-assisted total knee arthroplasty: secondary analysis of data from a randomized controlled trial; Cost-effectiveness of enoxaparin versus aspirin in the prevention of venous thromboembolism after total hip or knee arthroplasty: an analysis from the CRISTAL cluster-randomized trial; Cartilage regeneration and long-term survival in medial knee osteoarthritis patients treated with high tibial osteotomy and osteochondral autologous transfer system; Treatment of chronic and complex meniscal tears with arthroscopic meniscus repair augmented with collagen matrix wrapping: failure rate and functional outcomes; Long-term outcomes of multiligament knee injuries in American football players.

Return to play following craniotomy for non-traumatic brain lesions

ObjectiveReturn to play (RTP) decisions after cranial surgery are important to patients. Most published data relate to RTP following sports-related brain injury. This study investigated factors that influence neurosurgical RTP decision-making following craniotomy for non-traumatic brain lesions. MethodsA patient scenario-based survey was distributed to U.S. and Europe-based neurosurgeons via the American Association of Neurological Surgeons/Congress of Neurological Surgeons Tumor Section and the European Association of Neuro-Oncology. From one core patient scenario, 5 further scenarios were developed involving patients of varying age, sport preference, tumor pathology, and craniotomy approach. Respondents provided RTP recommendations and factors important in forming these recommendations. ResultsForty-one responses were received; Europe (48%), U.S. (37%). The most commonly cited factors influencing RTP decision-making across scenarios were symptomatic recovery (85.4%), resolution of blood and/or air on imaging (43.4%), and patient demand (31.7%). The sports with the longest average RTP timeline were boxing (10.3 months), rugby (8.7 months), and American football (8.5 months) in the core patient scenario. Twenty-nine percent of neurosurgeons requested neuroimaging before determining RTP recommendations in this scenario, more commonly in America than Europe (46.7% and 5.0% respectively, p = .006). ConclusionsAlthough limited by sample size, the data provides a foundation to support development of a systematic approach to RTP decision-making following craniotomy for brain lesions of non-traumatic etiology. Future work to develop consensus guidelines will benefit from objective data about outcomes, particularly in relation to repeat imaging prior to RTP.

Reduced Cortical Excitability is Associated with Cognitive Symptoms in Concussed Adolescent Football Players.

American tackle football is associated with high rates of concussion, leading to neurophysiological disturbances and debilitating clinical symptoms. Previous investigations of the neurophysiological effects of concussion have largely ignored aperiodic neurophysiological activity. We examined whether concussion during a season of high school football is related to changes in aperiodic and periodic neurophysiological activity and whether any such changes are associated with clinical outcomes. Pre- and post-season resting-state MEG data were collected from 91 high school football players, of whom 10 were diagnosed with concussion. Data were source-imaged, frequency-transformed and parameterized, and linear mixed models were used to examine effects of concussion on pre-to-post-season changes in neurophysiological activity. Scores on the Post-Concussive Symptom Inventory were correlated with pre-to-post-season neurophysiological changes to determine their clinical relevance. Concussion was associated with increased aperiodic exponents in superior frontal cortices, indicating a relative reduction in cortical excitability. This slowing of aperiodic neurophysiology mediated concussion effects on raw delta and gamma power and was associated with worse cognitive concerns across participants. Pre-to-post-season changes in aperiodic-corrected alpha and theta rhythmic activity were also decreased in posterior cortices in instances of concussion. These findings indicate that concussion alters both the excitability and rhythmic signaling of the cortex, with differing spatial topographies and implications for clinical symptoms.

Position-Specific Differences in Speed Profiles Among National Football League Scouting Combine Participants.

Gillen, ZM. Position-specific differences in speed profiles among NFL scouting combine participants. J Strength Cond Res XX(X): 000-000, 2024-This study examined the relationships between speed profiles and athletic performance measurements from the National Football League (NFL) Scouting Combine, and position-specific differences in speed profiles. Subjects included NFL Scouting Combines participants with valid scores for the 40-yard dash, as well as the 10- and 20-yard splits of the 40-yard dash (n = 2,156). Subjects were divided into the following position groups: defensive backs (DBs, n = 421), defensive linemen (DL, n = 356), linebackers (LBs, n = 261), offensive linemen (OL, n = 354), running backs (RBs, n = 217), tight ends (TEs, n = 122), quarterbacks (QBs, n = 108), and wide receivers (WRs, n = 317). Performance measures included 40-yard dash time (with 10- and 20-yard split times), bench press repetitions to failure, vertical jump height, broad jump distance, pro-agility time, and L-cone drill time. The 40-yard dash and its splits calculated vmax, τ, and amax to reflect speed profiles. One-way analysis of variances examined position-related differences. Pearson's product moment correlation coefficients examined relationships between performance measures and speed profile variables. Skill positions (DB and WR) had the greatest vmax and amax, and lowest τ, followed by big skill positions (LB, RB, TE, QB), followed by DL, then OL with the lowest vmax and amax, and highest τ. For skill and big skill positions, vmax, τ, and amax exhibited greater relationships with combine measures, whereas OL generally had the lowest relationships. The position-specific differences in this study demonstrate potential areas of strength and weakness for certain positions. This may help guide strength and conditioning coaches desiring to improve position-specific speed and acceleration capabilities for American football players.

Perceived Chronic Traumatic Encephalopathy and Suicidality in Former Professional Football Players

ImportanceParticipation in American-style football (ASF) has been linked to chronic traumatic encephalopathy neuropathological change (CTE-NC), a specific neuropathologic finding that can only be established at autopsy. Despite being a postmortem diagnosis, living former ASF players may perceive themselves to have CTE-NC. At present, the proportion and clinical correlates of living former professional ASF athletes with perceived CTE who report suicidality are unknown.ObjectiveTo determine the proportion, clinical correlates, and suicidality of living former professional ASF players with perceived CTE.Design, Setting, and ParticipantsA cross-sectional study within the Football Players Health Study at Harvard University was conducted from 2017 to 2020. Using electronic and paper surveys, this population-based study included former ASF players who contracted with a professional league from 1960 to 2020 and volunteered to fill out a baseline survey. Data for this study were analyzed from June 2023 through March 2024.ExposuresData included demographics, football-related exposures (eg, position, career duration), and current health problems (anxiety, attention-deficit/hyperactivity disorder, depression, diabetes, emotional and behavioral dyscontrol symptoms, headache, hyperlipidemia, hypertension, low testosterone level, pain, sleep apnea, and subjective cognitive function).Main Outcomes and MeasuresThe proportion of participants reporting perceived CTE. Univariable and multivariable models were used to determine clinical and suicidality correlates of perceived CTE.ResultsAmong 4180 former professional ASF players who volunteered to fill out a baseline survey, 1980 (47.4%) provided follow-up data (mean [SD] age, 57.7 [13.9] years). A total of 681 participants (34.4%) reported perceived CTE. Subjective cognitive difficulties, low testosterone level, headache, concussion signs and symptoms accrued during playing years, depressive/emotional and behavioral dyscontrol symptoms, pain, and younger age were significantly associated with perceived CTE. Suicidality was reported by 171 of 681 participants with perceived CTE (25.4%) and 64 of 1299 without perceived CTE (5.0%). After adjusting for established suicidality predictors (eg, depression), men with perceived CTE remained twice as likely to report suicidality (odds ratio, 2.06; 95% CI, 1.36-3.12; P < .001).Conclusions and RelevanceThis study found that approximately one-third of living former professional ASF players reported perceived CTE. Men with perceived CTE had an increased prevalence of suicidality and were more likely to have health problems associated with cognitive impairment compared with men without perceived CTE. Perceived CTE represents a novel risk factor for suicidality and, if present, should motivate the diagnostic assessment and treatment of medical and behavioral conditions that may be misattributed to CTE-NC.

Health outcomes of former division I college athletes

ABSTRACT Background Former professional collision sport (CS) athletes, particularly American football players, are at risk of developing chronic health conditions; however, little is known about the health outcomes of amateur athletes. Methods A 60-item health survey examined self-reported symptoms and diagnoses among former Division 1 Collegiate CS athletes and non- or limited-contact sport (non-CS) athletes. Binary logistic regressions tested the association between playing CS and health outcomes. Results Five hundred and two (6.2%) participants completed the survey: 160 CS athletes (mean age: 59.2, SD = 16.0) and 303 non-CS athletes (mean age: 54.0, SD = 16.9). CS athletes had increased odds of reported cognitive complaints and neuropsychiatric symptoms including memory (Padj < 0.01), attention/concentration (Padj = 0.01), problem solving/multi-tasking (Padj = 0.05), language (Padj = 0.02), anxiety (Padj = 0.04), impulsivity (Padj = 0.02), short-fuse/rage/explosivity (Padj < 0.001), and violence/aggression (Padj = 0.02). CS athletes also reported higher rates of sleep apnea (Padj = 0.02). There were no group differences in cardiovascular and physical health outcomes. Conclusions Former CS athletes reported more cognitive and neuropsychiatric complaints. The low response rate is a limitation of this study; however, over 500,000 athletes play college sports each year, thus research on long-term health outcomes in this population is critical.

Investigating Painkiller Use in Amateur Football: A Coach's Perspective.

Painkiller use in amateur sports and, especially, in football is increasingly being discussed, but the scientific data on this field are very limited. Therefore, the aim of this study was to investigate the prevalence of painkiller use in amateur football from the perspective of coaches, as well as to determine how and to which extent coaches can influence their teams in terms of painkiller use and prevention. Using an online questionnaire, a cross-sectional analysis of painkiller use in German amateur football from the 4th league to the lowest amateur classes was carried out from the perspective of team coaches. A total of 628 participants were contacted, and 400 (63.7%) completed the questionnaire completely and were therefore included in the evaluation. Of the 400 participating team coaches in amateur football, 369 (92.3%) were male and 31 (7.7%) were female. The coaches reported that 36.2% (SD = 29.1) of their players have used painkillers at some point due to football-related pain in their career. The majority of coaches believed that the use of painkillers is not compatible with competition (74%), and even more believed that it is not compatible with football training (90.8%). Furthermore, 56.2% of the coaches themselves had already taken painkillers in their own football career for football-related pain, and 64% had already bought over-the-counter painkillers without a prescription. The use of painkillers increased in the higher playing levels. The availability of painkillers in first aid kits was reported by around 60%, but they were reported as freely accessible in the dressing room by only 10% of the coaches. This is the first study to describe the painkiller use in amateur football from the perspective of coaches. The prevalence of painkiller use in this study was found to be significantly lower than what is indicated in the data from the existing literature. The majority of coaches see the use of painkillers during games and training as incompatible, even though there is a large proportion of coaches who have already bought over-the-counter painkillers for football-related pain. As the first scientific analysis of team coaches, this study provides fundamental data for the prevention of excessive painkiller use in amateur football.