ABSTRACT
PURPOSE: To test the effects of mental fatigue (MF) on tackling technique on the dominant and nondominant shoulders in rugby union. METHODS: Twenty male amateur rugby union players and a total of 953 tackles were analyzed. A randomized crossover counterbalanced design was used across a non-MF (control) and an MF condition. During each condition, each player performed 24 tackles, divided into 4 sets of 6 tackles (3 tackles on each shoulder). In the MF condition, players performed the Stroop Task between each set of tackles. A video recording of each tackle was used to evaluate each player's technical proficiency. A score of 1 point was awarded if a specific technique was performed correctly, and 0 point was given if not. The total score, measured in arbitrary units (AU) out of 11, represents the player's overall tackling proficiency. RESULTS: Overall, players displayed a significantly lower technical proficiency score in the MF condition compared to control (set 2: control 7.30 [7.04-7.57] AU vs MF 6.91 [6.70-7.12] AU, P = .009, effect size (ES) = 0.30 small and set 3: control 7.34 [7.11-7.57] AU vs MF 6.88 [6.66-7.11] AU, P = .002, ES = 0.37 small). For the nondominant shoulder, players had a significantly lower technical proficiency score during the MF condition at set 2 (control 7.05 [6.68-7.41] AU vs MF 6.69 [6.42-6.96] AU, P = .047, ES = 0.29 small) and set 3 (control 7.14 [6.83-7.45] AU vs MF 6.61 [6.35-6.87] AU, P = .007, ES = 0.49 small). CONCLUSIONS: MF can diminish a player's overall tackling proficiency, especially when tackling on the nondominant shoulder. The physiological mechanism for this finding may be impaired executive function and suboptimal functioning of neural signals and pathways, which result in less skillful coordination of movement. To further understand and explain MF-induced physiological changes in tackling, the feasibility of monitoring brain activity (such as electroencephalogram) and neuromuscular function (such as electromyogram) needs to be investigated. The findings from this study may also contribute to the development of more effective tackle training programs for injury prevention and performance.
Subject(s)
Football , Humans , Male , Athletes , Football/physiology , Rugby , Upper Extremity , Video Recording , Cross-Over StudiesABSTRACT
BackgroundSARS-CoV-2 seroprevalence studies have largely focused on adults but little is known about spread in children. We determined SARS-CoV-2 seroprevalence in children and adolescents from Arkansas over the first year of the COVID-19 pandemic. MethodsWe tested remnant serum samples from children from 1-18 years who visited Arkansas hospitals or clinics for non-COVID19-related reasons from April, 2020 through April, 2021 for SARS-CoV-2 antibodies. We used univariable and multivariable regression models to determine association between seropositivity and participant characteristics. ResultsAmong 2400 participants, seroprevalence rose from 7.9% in April/May 2020 (95% CI, 4.9-10.9%) to 25.8% in April 2021 (95% CI, 22.2-29.3%). Hispanic and black children had a significantly higher association with antibody positivity than white children in multiple sampling periods. ConclusionsBy spring 2021, most children in Arkansas had not been infected with SARS-CoV-2. With the emergence of SARS-CoV-2 variants, recognition of long-term effects of COVID-19, and the lack of an authorized pediatric SARS-CoV-2 vaccine, these results highlight the importance of including children in SARS-CoV-2 public health, clinical care, and research strategies. These findings are important for state and local officials as they consider measures to limit SARS-CoV-2 spread in schools and daycares for the 2021-2022 school year.
ABSTRACT
ObjectiveOur objective is to estimate CoV-2 infection rates in a rural state using seroprevalence of antibodies to CoV-2 as an indicator of infection. Study Design and SettingThis is a single-site study within an academic center and regional programs within the state of Arkansas. We obtained residual serum samples from a convenience sample of adults who were outpatients and came to the hospital or regional clinic for non-COVID-related reasons. We collected remnant in three time periods (August 15 to September 5, September 12 to October 24, and November 7 to December 19). ResultsIn 2020, the overall age, gender, and race standardized prevalence of CoV-2 antibodies was 2.6% (August to September), 4.1% (September to October), and 7.4% (November to December). There was no difference in seroprevalence between urban compared to rural areas. Positive tests were not uniformly distributed across racial and ethnic minorities. Higher seroprevalence rates were found in Hispanics and Blacks or African Americans compared to whites across all time periods. ConclusionsIn a state with a large rural population, 2.6-7.4% of people experienced CoV-2 infection by December 2020. Blacks and Hispanics had disproportionately higher rates of CoV-2 infections than whites. What is new?O_ST_ABSKey findingsC_ST_ABSIn this prospective convenience sampling of remnant sera, we found increasing seroprevalence from 2.6% to 7.4% (August 2020 to December 2020). Higher seroprevalence rates were found in Hispanics and Blacks or African Americans compared to whites across all time periods, and no difference was determined between those individuals from rural or urban areas. What this adds to what is knownIn a largely rural population, Blacks and Hispanics had disproportionately higher rates of CoV-2 infections than whites, and these populations need to be studied further regarding outcomes. What is the implication?There are health disparities that exist regarding CoV-2 infections, and we should target vaccination information and education to these groups. Highlights- SARS-CoV-2 infections increased from 2.6% to 7.4% from August to December 2020. - Higher seroprevalence was found in Hispanics and Blacks as compared to whites. - There was no difference in the seroprevalence in rural compared to urban areas.
