Caffeine is commonly used to improve athletic performance across a variety of sports. Previously, the CYP1A2 gene has been shown to modify the effects of caffeine on endurance performance. The effect of caffeine on strength and power activities is unclear and may differ depending on an individual’s CYP1A2 genotype. A randomized controlled trial was used to determine whether caffeine impacts strength and power, determined by the handgrip and vertical jump tests, respectively, and whether CYP1A2 genotype modifies any effects. Competitive male athletes (age = 25 ± 4 years) completed vertical jump (n = 97), and handgrip tests (n = 102) under three conditions: 0 (placebo), 2, or 4 mg of caffeine per kilogram of body mass (in milligrams per kilogram). CYP1A2 (rs762551) genotype was determined from saliva samples. No differences between caffeine doses and placebo were observed for strength or power; however, significant Caffeine × Gene interactions were observed for all exercise tests. Individuals with the CC genotype experienced a 12.8% decrease in handgrip strength with 4 mg/kg of caffeine compared with placebo (53 ± 11 kg vs. 61 ± 17 kg, p = .02). No differences were observed in those with the AC or AA genotypes. Despite observing a significant Caffeine × Gene interaction for vertical jump performance, no differences were observed between caffeine doses and placebo for all genotypes. In summary, caffeine (4 mg/kg) worsened handgrip strength performance in those with the CC genotype, but no differences were observed in those with the AC or AA genotypes. Athletes may want to consider their CYP1A2 genotype prior to using caffeine to improve muscle strength.
Oriana Wong, Keiko Marshall, Marc Sicova, Nanci S. Guest, Bibiana García-Bailo, and Ahmed El-Sohemy
Jaison L. Wynne and Patrick B. Wilson
Beer is used to socialize postexercise, celebrate sport victory, and commiserate postdefeat. Rich in polyphenols, beer has antioxidant effects when consumed in moderation, but its alcohol content may confer some negative effects. Despite beer’s popularity, no review has explored its effects on exercise performance, recovery, and adaptation. Thus, a systematic literature search of three databases (PubMed, SPORTDiscus, and Web of Science) was conducted by two reviewers. The search resulted in 16 studies that were appraised and reviewed. The mean PEDro score was 5.1. When individuals are looking to rehydrate postexercise, a low-alcohol beer (<4%) may be more effective. If choosing a beer higher in alcoholic content (>4%), it is advised to pair this with a nonalcoholic option to limit diuresis, particularly when relatively large volumes of fluid (>700 ml) are consumed. Adding Na+ to alcoholic beer may improve rehydration by decreasing fluid losses, but palatability may decrease. These conclusions are largely based on studies that standardized beverage volume, and the results may not apply equally to situations where people ingest fluids and food ad libitum. Ingesting nonalcoholic, polyphenol-rich beer could be an effective strategy for preventing respiratory infections during heavy training. If consumed in moderation, body composition and strength qualities seem largely unaffected by beer. Mixed results that limit sweeping conclusions are owed to variations in study design (i.e., hydration and exercise protocols). Future research should incorporate exercise protocols with higher ecological validity, recruit more women, prioritize chronic study designs, and use ad libitum fluid replacement protocols for more robust conclusions.
Margot A. Rogers, Michael K. Drew, Renee Appaneal, Greg Lovell, Bronwen Lundy, David Hughes, Nicole Vlahovich, Gordon Waddington, and Louise M. Burke
The Low Energy Availability in Females Questionnaire (LEAF-Q) was validated to identify risk of the female athlete triad (triad) in female endurance athletes. This study explored the ability of the LEAF-Q to detect conditions related to low energy availability (LEA) in a mixed sport cohort of female athletes. Data included the LEAF-Q, SCOFF Questionnaire for disordered eating, dual-energy X-ray absorptiometry-derived body composition and bone mineral density, Mini International Neuropsychiatric Interview, blood pressure, and blood metabolic and reproductive hormones. Participants were grouped according to LEAF-Q score (≥8 or <8), and a comparison of means was undertaken. Sensitivity, specificity, and predictive values of the overall score and subscale scores were calculated in relation to the triad and biomarkers relevant to LEA. Fisher’s exact test explored differences in prevalence of these conditions between groups. Seventy-five athletes (18–32 years) participated. Mean LEAF-Q score was 8.0 ± 4.2 (55% scored ≥8). Injury and menstrual function subscale scores identified low bone mineral density (100% sensitivity, 95% confidence interval [15.8%, 100%]) and menstrual dysfunction (80.0% sensitivity, 95% confidence interval [28.4%, 99.5%]), respectively. The gastrointestinal subscale did not detect surrogate markers of LEA. LEAF-Q score cannot be used to classify athletes as “high risk” of conditions related to LEA, nor can it be used as a surrogate diagnostic tool for LEA given the low specificity identified. Our study supports its use as a screening tool to rule out risk of LEA-related conditions or to create selective low-risk groups that do not need management as there were generally high negative predictive values (range 76.5–100%) for conditions related to LEA.
Bent R. Rønnestad, Joar Hansen, Thomas C. Bonne, and Carsten Lundby
Purpose: The present case report aimed to investigate the effects of exercise training in temperate ambient conditions while wearing a heat suit on hemoglobin mass (Hbmass). Methods: As part of their training regimens, 5 national-team members of endurance sports (3 males) performed ∼5 weekly heat suit exercise training sessions each lasting 50 minutes for a duration of ∼8 weeks. Two other male athletes acted as controls. After the initial 8-week period, 3 of the athletes continued for 2 to 4 months with ∼3 weekly heat sessions in an attempt to maintain acquired adaptations at a lower cost. Hbmass was assessed in duplicate before and after intervention and maintenance period based on automated carbon monoxide rebreathing. Results: Heat suit exercise training increased rectal temperature to a median value of 38.7°C (range 38.6°C–39.0°C), and during the initial ∼8 weeks of heat suit training, there was a median increase of 5% (range 1.4%–12.9%) in Hbmass, while the changes in the 2 control athletes were a decrease of 1.7% and an increase of 3.2%, respectively. Furthermore, during the maintenance period, the 3 athletes who continued with a reduced number of heat suit sessions experienced a change of 0.7%, 2.8%, and −1.1%, indicating that it is possible to maintain initial increases in Hbmass despite reducing the weekly number of heat suit sessions. Conclusions: The present case report illustrates that heat suit exercise training acutely raises rectal temperature and that following 8 weeks of such training Hbmass may increase in elite endurance athletes.
Jolan Kegelaers, Paul Wylleman, I. (Belle) N.A. van Bree, Francesco Wessels, and Raôul R.D. Oudejans
Coaching in elite sports can be a highly volatile and stressful profession. Nevertheless, limited knowledge is available on how coach stressors impact elite-level coaches’ mental health. The present study therefore aimed to assess the self-perceived impact of coach stressors on coaches’ mental health, in terms of psychological and social well-being, as well as the prevalence of symptoms of a number of common mental disorders. Furthermore, the role of resilience was examined as a potential protective resource against mental health issues in coaches. Data were collected cross-sectionally, using an online survey with 119 elite-level coaches from the Netherlands and Belgium. Results showed that, although coach stressors were commonly experienced, the self-perceived impact on mental health was low to moderate. Nevertheless, symptoms of common mental disorders were prevalent within the coaches, ranging from 39% for depression/anxiety to 19% for distress and adverse alcohol use. Furthermore, organizational stressors were found to be a positive predictor for symptoms of depression/anxiety, whereas resilience was a negative predictor. The results highlight the need for more research and attention to the mental health of coaches in elite sports.
Tom O. Mitchell, Adam Gledhill, Ross Shand, Martin A. Littlewood, Lewis Charnock, and Kevin Till
There is an increasing awareness of the importance of the environment in academy players’ development, yet limited research has investigated players’ perceptions of their talent development environments (TDEs). This study focused on academy soccer players’ perceptions of their TDE and compared perceptions across the English soccer academy categorization (CAT) system. A total of 136 U.K.-based male soccer players (M age = 17.7, SD = 1.03 years) representing all four categories (1 = highest to 4 = lowest) of soccer academies aligned to professional soccer clubs completed the TDE Questionnaire-5 (TDEQ-5). The players within the CAT1 academies had significantly more positive perceptions of their support network (p = .01) and holistic quality preparation (p = .03) than their CAT3 counterparts. Across CAT2–CAT3, holistic quality preparation was the least positively perceived subscale within the TDEQ-5, suggesting the need for additional coach education in this area. Soccer academies should consider how they ensure that all areas of their service are associated with optimal TDEs by offering a well-communicated and holistic development experience for their players to enhance effective personal and player development. The findings may have implications for player experience and associated progression rates of lower categorized soccer academies.
Seamus Kelly and Niall O’Regan
This article explores how the 2020 edition of the Union of European Football Association’s (UEFA) Coaching Convention impacts coach education in the Football Association of Ireland (FAI), a member of the UEFA. First, this article provides a brief history of the UEFA Coaching Convention and it’s historical benefits. Second, the UEFA Coaching Convention’s principles and practices of adult learning and reality-based learning are identified, along with the national association’s responsibilities for their implementation. Third, we outline the four main changes to the 2020 UEFA Coaching Convention, and fourth, following an overview of coach education in the FAI, we identify how the FAI’s Coach Education Department adopts a constructivist, learner-centered approach when implementing the UEFA adult learning and reality-based learning principles. Fifth, we discuss some of the implemented and planned coach education initiatives in the FAI and provide an overview of the FAI’s redeveloped coach education pathway, which was launched in August 2020 for implementation from 2021 to 2025. The article concludes with an overview of the future of coach education in the FAI and suggestions for further research.
Deborah S. Baxter and Oleg A. Sinelnikov
Purpose: The purpose of this study was to explore the extent of changes taking place within the context, structure, and culture of university physical education teacher education programs facilitating high-stakes educative Teacher Performance Assessment policy. Method: Utilizing a multiple-case study design framed by analytical dualism, eight physical education teacher education faculty from eight different programs who had direct involvement in the high-stakes educative Teacher Performance Assessment process were investigated. Data from semi-structured individual interviews, focus group interviews, and documents were interpretively analyzed. Results: Faculty reacted in three distinct ways to the process of change: prevailers, conceders, or exceeders. The process appeared to be based upon an implementation continuum from isolation to internalization. Discussion/Conclusions: University programs have a responsibility to prepare effective physical education teachers who use the best practices for teaching. It is imperative for physical education teacher education faculty to reflect upon the impetus and impact of changes made to their programs.
Weidong Li, Lian Ma, Ping Xiang, and Yan Tang
Purpose: The purpose of this study was to review and evaluate the quality of fidelity of implementation (FOI) reported in experimental research in physical education pedagogy published in the Research Quarterly for Exercise and Sport and the Journal of Teaching in Physical Education using a five-component conceptual framework. Methods: Thirty-five intervention studies were coded using a five-item FOI checklist with indicators. For each of the five items, frequencies and percentages were calculated. Results: Authors of intervention studies reported components of FOI including (a) 35 studies assessing program adherence, (b) eight studies assessing dosage/program durations, (c) 30 studies assessing program delivery quality, (d) eight studies assessing participant responses to program interventions, and (e) 19 studies assessing program differentiation. The most frequently reported FOI components were program adherence, program delivery quality, and program differentiation. Conclusions: Researchers have begun to realize the critical importance of FOI in intervention research. Most researchers selected certain FOI components to assess and report at their own discretion. Researchers may need to pay more attention to FOI. The five-component conceptual framework is one method for doing this assessment.