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The literature describing the effects of mental fatigue (MF) has grown tremendously. This is accompanied by identification of a host of performance-determining parameters affected by MF. MF results from prolonged cognitive effort and predominantly affects physical, technical, tactical, and perceptual–cognitive dimensions of sport, while physiological parameters (eg, heart rate, lactate) and physical aspects of maximal and supramaximal efforts are predominantly unaffected. The aim of this paper was to provide an overview of the parameters described in the literature as influenced by MF. By identifying the different parameters, we not only see how they affect the performance of athletes but also raise concerns about the potentially increased injury risk due to MF. Preliminary evidence suggests that subsequent disturbances in balance, motor skills, and decision-making processes could potentially increase the vulnerability to injury. An abundance of lab-based studies looked into the effects of MF on performance; however, many questions remain about the mechanisms of origin and neurophysiological causes of MF, and only small steps have been taken to translate this knowledge into practice. Thus, there is a need for more research into the underlying mechanisms of MF and the role of the brain, as well as more applied research with a high ecological validity that also takes into account the potential increased risk of injury due to MF.

Background: Adult-led organized settings for children (eg, classrooms) provide opportunities for physical activity (PA). The structure of setting time may influence inequalities (ie, unequalness) in the distribution of PA. This study examined differences in PA inequality by setting and time-segment purpose in time-segmented organized group settings for children. Methods: PA and setting meetings were assessed using accelerometer and video observation data from school, before-/after-school, and youth club groups (n = 30) for third- through sixth-grade children (n = 699) in 2 rural US communities. Meetings (n = 130) were time-segmented into smaller units (sessions; n = 835). Each session was assigned a purpose code (eg, PA). Accelerometer data were paired with the meetings and sessions, and the Gini coefficient quantified inequality in activity counts and moderate to vigorous PA minutes for each segment. Beta generalized estimating equations examined differences in PA inequality by setting and session purpose. Results: Activity count inequality was lowest (P < .05) during youth club meetings (Gini = 0.17, 95% CI, 0.14–0.20), and inequality in moderate to vigorous PA minutes was greatest (P < .01) during school (Gini = 0.34, 95% CI, 0.30–0.38). Organized PA sessions (Gini = 0.20, 95% CI, 0.17–0.23) had lower activity count inequality (P < .0001) than academic (Gini = 0.30, 95% CI, 0.27–0.34), enrichment (Gini = 0.31, 95% CI, 0.27–0.36), and nonactive recreation (Gini = 0.30, 95% CI, 0.25–0.34) sessions. Inequality in moderate to vigorous PA minutes was lower (P < .05) in organized PA (Gini = 0.26, 95% CI, 0.20–0.32) and free play (Gini = 0.28, 95% CI, 0.19–0.39) than other sessions. Conclusions: PA inequality differed by setting time structure, with lower inequality during organized PA sessions. The Gini coefficient can illuminate PA inequalities in organized settings and may inform population PA improvement efforts in rural communities.

The limited sample size in gait studies has hampered progress in the field. This challenge could be addressed through multicenter studies, thereby leveraging data sets from different laboratories. This study compared 3-dimensional lower-extremity running kinematics between the Biomechanics and Motor Control Laboratory, Federal University of ABC (Brazil), and the Running Injury Clinic, University of Calgary (Canada). Three-dimensional lower-extremity kinematics from 23 male runners were collected from each laboratory using comparable instrumentation and experimental procedures. The 3-dimensional hip, knee, and ankle angles were compared within and between centers using root-mean-square deviation. Two-sample t tests Statistical Parametric Mapping tested the hypothesis that the data from both laboratories were not different. The sagittal plane hip, knee, and ankle angles were similar between laboratories, while notable differences were observed for frontal (hip and ankle) and transverse (hip and knee) plane angles. The average interlaboratory root-mean-square deviation (2.6°) was lower than the intralaboratory root-mean-square deviation (Biomechanics and Motor Control = 4.8°, Running Injury Clinic = 5.6°), with the ankle transverse angle displaying the smallest, and the knee transverse angle displaying the largest variability. This study demonstrates the potential of combining gait kinematics data from different laboratories to increase sample size, but frontal and transverse plane data should be considered with caution.

Background: Physical activity (PA) and nutrition in children have an impact on overall physical and mental well-being, cognitive, and social development. This study aims to report on the best current available evidence on PA, body composition proxies, and nutritional status of South African children and adolescents, based on the published findings between 2018 and 2022, which comprise the 2022 Healthy Active Kids South Africa Report Card. Methods: A comprehensive literature search of online databases, along with hand searching and a gray literature search, was conducted based on PA, body composition proxies, and nutrition indicators defined, in part, by the Active Healthy Kids Global Alliance. Results: Compared with the 2018 report card, there was an improvement in the majority of PA indicators which include overall PA (B–), active transportation (B–), physical fitness (B–), and government policy and programs (C). Body composition proxies and most of the nutrition indicators remained unchanged. The indicators that regressed from 2018 to 2022 included community and environmental influences (D), as well as participation in organized sport (D–). Conclusions: Despite the apparent improvement in overall PA levels in children and adolescents, there is a lack of tangible evidence of actual implementation of policies and programs. There was also a lack of nationally representative data for most indicators. Overall, there is a need to identify intersectoral, equitable approaches for promoting PA and healthy eating in South African children and adolescents and ongoing monitoring and surveillance.

The modern era of running shoes began in the 1960s with the introduction of simple polymer midsole foams, and it ended in the late 2010s with the introduction of advanced footwear technology (AFT). AFT is characterized by highly compliant, resilient, and lightweight foams with embedded, rigid, longitudinal architecture. This footwear complex improves a runner’s efficiency, and it introduced a step change in running performance. Purpose: This review serves to examine the current state of knowledge around AFT—what it is and what we know about its ingredients, what benefits it confers to runners, and what may or may not mediate that benefit. We also discuss the emerging science around AFT being introduced to track-racing spikes and how it is currently regulated in sporting contexts. Conclusions: AFT has changed running as a sport. The construction of AFT is grossly understood, but the nature of the interacting elements is not. The magnitude of the enhancement of a runner’s economy and performance has been characterized and modeled, but the nuanced factors that mediate those responses have not. With these knowns and unknowns, we conclude the review by providing a collection of best practices for footwear researchers, advice for runners interested in AFT, and a list of pertinent items for further investigation.

Objectives: Dietary strategies to improve arachidonic acid:eicosapentaenoic acid (AA:EPA) ratios are of interest due to potential reductions in inflammation and oxidative stress following exercise. The aim of this study was to investigate the impact of a novel dietary intervention, that is, the ingestion of 30 g of dark chocolate, on blood lipid profiles and gut microbiota composition in elite male soccer players. Methods: Professional male soccer players were randomly assigned to the experimental group (DC) provided with 30 g of dark chocolate or to the control group (WC), provided with 30 g of white chocolate, for 30 days. Before and after intervention, blood, fecal sample, and anthropometry data were collected. For each outcome, two-way repeated-measure analysis of variance was used to identify differences between baseline and endpoint (Week 4), considering treatment (dark chocolate, white chocolate) as intersubjects’ factors. Metagenomic analysis was performed following the general guidelines, which relies on the bioBakery computational environment. Results: DC group showed increased plasma polyphenols (from 154.7 ± 18.6 μg gallic acid equivalents/ml to 185.11 ± 57.6 μg gallic acid equivalents/ml, Δ pre vs. post = +30.41 ± 21.50) and significant improvements in lipid profiles: total cholesterol (Δ −32.47 ± 17.18 mg/dl DC vs. Δ −2.84 ± 6.25 mg/dl WC, Time × Treatment interaction p < .001), triglycerides (Δ −6.32 ± 4.96 mg/dl DC vs. Δ −0.42 ± 6.47 mg/dl WC, Time × Treatment interaction p < .001), low-density lipoprotein (Δ −18.42 ± 17.13 mg/dl vs. Δ −2.05 ± 5.19 mg/dl WC, Time × Treatment interaction p < .001), AA/EPA ratio (Δ −5.26 ± 2.35; −54.1% DC vs. Δ −0.47 ± 0.73, −6.41% WC, Time × Treatment interaction p < .001) compared with WC group. In addition, 4 weeks of intervention showed a significant increase in high-density lipoprotein concentration in DC group (Δ + 3.26 ± 4.49 mg/dl DC vs. Δ −0.79 ± 5.12 mg/dl WC). Microbial communities in the DC group maintained a slightly higher microbial stability over time (exhibiting lower within-subject community dissimilarity). Conclusion: Ingesting 30 g of dark chocolate over 4 weeks positively improved AA:EPA ratio and maintained gut microbial stability. Dark chocolate ingestion represents an effective nutritional strategy to improve blood lipid profiles in professional soccer players. What Are the Findings? Ingesting 30 g of dark chocolate for 4 weeks positively influences blood lipid AA: EPA ratio while maintaining gut microbial stability. What This Study Adds? Dietary intake of specific foods such as dark chocolate represents an alternative strategy to support the health and recovery of elite soccer players. What Impact Might This Have on Clinical Practice in the Future? From a clinical and translational perspective, dark chocolate ingestion positively modulates favorable blood lipid profiles and polyunsaturated fatty acid metabolism while maintaining gut microbial stability. Dark chocolate ingestion may be considered as an effective nutritional strategy in elite sport environments during periods of high-intensity training and congested competitions. Further research is required to determine functional outcomes associated with the observed improvements in blood lipid profiles.

Background: Although the prescription of physical activity in clinical care has been advocated worldwide, in the Netherlands, “Exercise is Medicine” (E = M) is not yet routinely implemented in clinical care. Methods: A set of implementation strategies was pilot implemented to test its feasibility for use in routine care by clinicians in 2 departments of a university medical center. An extensive learning process evaluation was performed, using structured mixed methods methodology, in accordance with the Reach, Effect, Adoption, Implementation, and Maintenance framework. Results: From 5 implementation strategies employed (education, E = M tool embedded in the electronic medical records, lifestyle coach situated within the department, overviews of referral options, and project support), the presence of adequate project support was a strong facilitator of the implementation of E = M. Also, the presence of the lifestyle coach within the department seemed essential for referral rate. Although clinicians appreciated the E = M tool, barriers hampered its use in practice. Conclusions: Specific implementation strategies, tailored to the setting, are effective in facilitating the implementation of E = M with specific regard to education for clinicians on E = M, deployment of a lifestyle coach within a department, and project coordination. Care providers do see a future for lifestyle coaches who are structurally embedded in the hospital, to whom they can easily refer.

Background: This study aimed to compare the overall prevalence, stratified by sex and age group of global physical activity (GPA), active commuting to school (ACS), and sedentary behavior (SB) among adolescents from ten Latin American countries, and to assess the correlation of Development Index with the indicators. Methods: This research is grounded on data from the Global School-Based Student Health Survey (2009–2015) and the 2015 Brazilian National School Health Survey. The prevalence and 95% confidence intervals for GPA (≥5 d/wk), ACS (≥1 d/wk), and SB (>2 h/d) were calculated using the chi-square test to compare the sexes (male; female) and age group (≤13 y; 14 y; 15 y; ≥16 y). We also performed Pearson correlation analysis with the Human Development Index. Results: The prevalence of indicators ranged from 16.1% to 28.2% for GPA, from 56.7% to 71.2% for ACS, and from 20.7% to 62.6% for SB. Boys generally had a higher prevalence of GPA and ACS, and girls had a higher prevalence of SB. The prevalence of the indicators by age group varied between countries, with significant differences observed in some, depending on each indicator. A positive correlation was observed between Human Development Index, GPA, and SB. Conclusion: Health promotion policies must include guidelines that encourage and promote a more active and less sedentary lifestyle among young people in Latin America, considering specific groups, the local socioeconomic context, and differences between countries.

Background: Despite the existence of physical activity policies across many countries, insufficient physical activity remains a major global public health problem. Physical inactivity is an emergent feature of complex systems; it results from a wide range of factors at multiple levels that interact to influence behavior. Traditional approaches to public policy often fail within complex systems, largely due to unpredictability in how the system will respond. Adaptive policies, which are designed to allow for uncertainty about future system behavior and to change over time, may offer a promising solution. In this paper, we introduce the concept of adaptive policies and illustrate how this innovative approach to policy making may be beneficial for reducing physical inactivity. Design: Drawing on existing literature and guiding principles for policy making, we provide 3 examples to illustrate how the concept of adaptive policies can be applied to address physical inactivity. Discussion: The examples illustrate how changes to the way policies and interventions are developed, implemented, and evaluated could help to overcome some of the limitations in existing practices. A key challenge will be engaging policymakers to take a broader perspective of the physical activity system, develop policies that are designed to be adaptable across a range of different future scenarios, and embrace uncertainty and long-term adaptability. Conclusion: Adaptive policies may support decision makers globally to achieve the widespread and sustained changes necessary to increase population levels of physical activity.