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This study investigated the effect of oral and topical sodium bicarbonate (SB) on soccer-specific performance during simulated soccer exercise. In a block randomized, double-blind, crossover design, 10 collegiate male soccer players (stature: 181.7 ± 3.2 cm, body mass: 81.7 ± 10.5 kg) performed soccer-specific performance tests (countermovement jumps, Illinois agility, 8 × 25 m repeated sprints) throughout a 90-min soccer-specific aerobic field test (SAFT90) following 0.3 g/kg body mass SB in capsules (SB-ORAL), 0.9036 g/kg body mass PR Lotion (SB-LOTION), or placebo capsules and lotion (PLA). Soccer-specific performance tests were conducted pre-SAFT90, during half-time and post-SAFT90. Blood samples were analyzed for acid–base balance (pH; bicarbonate, ${\mathrm{HCO}}_3^{-}$ ) and strong ions (sodium, Na⁺; potassium, K⁺). Average sprint times were quicker for SB-ORAL than PLA during half-time (3.7%; p = .049; g = .57) and post-SAFT90 (4.9%; p = .041; g = .66). SB-ORAL increased pH and ${\mathrm{HCO}}_3^{-}$ prewarm-up and during half-time (p < .05), and lowered K⁺ during half-time (p = .035) compared with PLA. SB-LOTION increased pH (p = .019) and lowered K⁺ (p = .012) during half-time compared with PLA. SB-LOTION increased Na⁺ postexercise compared with PLA (p = .008). Repeated sprint times during simulated soccer exercise improved for SB-ORAL, which might have been mechanistically underpinned by elevated blood buffering capacity and greater regulation of strong ion concentration. Consuming SB in capsules is a more effective strategy than topical SB application for improving blood buffering capacity and repeated sprint performance throughout competitive soccer matches.

Background: This study aimed to explore the associations between moderate to vigorous physical activity (MVPA) and sedentary time with renal function indices in adolescents with kidney disease. Methods: A cross-sectional study was conducted on 719 adolescents (median age 15 y, 40.6% female) with kidney disease from the National Health and Nutrition Examination Survey 2007–2016. The exposures were MVPA time and sedentary time. Renal metabolic parameters included serum uric acid (SUA), creatinine, blood urea nitrogen, the estimated glomerular filtration rate (eGFR), and the albumin creatinine ratio. Weighted multivariate regression analysis was used to estimate associations between exposures and outcomes. Results: After stratifying MVPA time, the regression effect values β (95% CI) for MVPA on SUA (Q2: −0.22 [−0.41 to −0.03]; Q3: −0.32 [−0.53 to −0.11]) and creatinine (Q2: −0.08 [−0.15 to −0.01]; Q3: −0.04 [−0.11 to 0.03]) gradually decreased with increasing MVPA time. In males (−0.76 [−1.19 to −0.32]), MVPA time was significantly associated with lower SUA levels compared with females (−0.14 [−0.38 to 0.10]). Notably, female adolescents who had an MVPA time exceeding 420 minutes exhibited lower albumin creatinine ratio (−75.37 [−146.63 to −4.11]). In addition, both recreational MVPA time (−0.26 [−0.45 to −0.06]) and sedentary time (−3.15 [−5.83 to −0.46]) were negatively associated with eGFR. Conclusions: Our study found an association between MVPA and lower levels of SUA in male adolescents with kidney disease and albuminuria in female adolescents with kidney disease. In addition, MVPA was also negatively associated with creatinine and eGFR, whereas sedentary time was only associated with eGFR. Further studies are needed to confirm these findings.

Background: Although the physical activities have demonstrated efficacy in improving physical self-perception, the findings of available studies in college students were conflicting. This review aimed to examine the effects of physical activity interventions on physical self-perception in college students. Methods: Web of Science, PubMed, Cochrane Library, EBSCOhost, Embase, Scopus, CNKI, WanFang, and Chinese Technical Periodicals were searched from inception to April 2024. Studies were included if they were randomized controlled trials (RCTs) or non-RCTs (non-RCTs) that examined the effects of physical activity interventions on college students’ physical self-perception. Random-effects models were used in meta-analyses to synthesize effect sizes. Results: Forty studies (17 RCTs and 23 non-RCTs) with 4955 participants were included in this meta-analysis. Overall, physical activity interventions had small to moderate significant effect on physical self-worth (standardized mean difference [SMD] = 0.44, P < .00001), perceived sports competence (SMD = 0.60, P < .00001), perceived physical condition (SMD = 0.45, P < .00001), perceived physical strength (SMD = 0.53, P < .00001), and perceived body attractiveness (SMD = 0.54, P < .00001). Significant differences were observed in study design (P = .031–.039), intervention type (P = .003–.031), and intervention duration (P = .002–.036) for some aspects of physical self-perception, such as perceived physical strength and perceived body attractiveness. Conclusions: Physical activity interventions have beneficial effects on physical self-perception in college students, especially those conducted for 12 weeks, 3 times or more per week, lasting 90 minutes or more per session. Large, high-quality RCTs are required to further confirm these findings.

Background: Given the emergence of climate change and health risks, this review examined potential relationships between varying indicators of climate change, movement behaviors (ie, physical activity [PA], sedentary behavior, and sleep), and health. Methods: Seven databases were searched in March 2020, April 2023, and April 2024. To be included, studies must have examined indicators of climate change and at least one of the movement behaviors as either an exposure or a third variable (ie, mediator/moderator), and a measure of health as outcome. Evidence was summarized by the role (mediator/moderator) that either climate change or movement behavior(s) has with health measures. Relationships and directionality of each association, as well as the strength and certainty of evidence were synthesized. Results: A total of 79 studies were eligible, representing 6,671,791 participants and 3137 counties from 25 countries (40% low- and middle-income countries). Of 98 observations from 17 studies that examined PA as a mediator, 34.7% indicated that PA mediated the relationship between climate change and health measure such that indicators of adverse climate change were associated with lower PA, and worse health outcome. Of 274 observations made from 46 studies, 28% showed that PA favorably modified the negative association between climate change and health outcome. Evidence was largely lacking and inconclusive for sedentary behavior and sleep, as well as climate change indicators as an intermediatory variable. Conclusions: PA may mitigate the adverse impact of climate change on health. Further evidence is needed to integrate PA into climate change mitigation, adaptation, and resilience strategies.

Purpose: The traditional understanding of how coaches plan for sporting performance is rooted in the assumption that coaches create periodized plans underpinned by physiological principles, thereby providing scientific credibility to their work. In contrast, there remains a paucity of literature exploring how coaches understand or think about their planning practices. The purpose of this study was to generate new knowledge regarding what information coaches actually consider within their planning processes and how they actually approach the task of planning. Method: Using rigorous, in-depth interviews, this study examined athletics coaches’ understandings of their everyday planning practices, in an attempt to contribute to narrowing the gap between academic research and real-world application. Twenty-eight highly experienced, high-performance track-and-field coaches based in England (female, n = 1; male, n = 27) were recruited. The coaches were from the throwing disciplines (n = 10) and endurance running (n = 18). Coaches were interviewed about their planning process, using a maximum of 3 semistructured interviews per coach, spaced across a full athletics season. In total, this generated 68 hours of data. Results: The analysis demonstrated that, while the participant coaches utilized the principles of periodization, their planning activities were not limited to this issue. The findings highlighted how the coaches conceptualized successful athletic performance in a holistic way; that is, planning is multifaceted in nature. Conclusion: This study presents a holistic picture of the complexity of coaches’ planning, detailing the considerable time and attention given to planning for athletes’ psychological, personal, and social development, to enhance athlete performance and development.

Purpose: To identify the physical conditioning and functional injury-screening characteristics of elite female soccer players. Methods: This review was prospectively registered (PROSPERO CRD4202346765). Searches were conducted in PubMed/MEDLINE, Cochrane Library, Scopus, and Web of Science (from inception in March 2023 to July 2023). Updated searches were conducted in October 2023 and April 2024. Included studies were quantitative studies conducted on female soccer players. Main outcomes were functional and physical profiles. Screening, data extraction, and quality assessment (Quality Assessment Tool for Quantitative Studies and the Oxford Levels of Evidence scales) were performed. Mean differences between preseason and in-season testing periods were estimated by Hedges g effect size. Methods and results were reported according to PRISMA guidelines. Results: The search yielded 1727 articles, of which 10 were included. Overall methodological quality of the studies was strong, with a moderate level of evidence. Players exhibited mean maximal oxygen uptake of 52.6 (4.5) mL·min⁻¹·kg⁻¹, 20-m linear-sprint performance of 3.58 (0.18) seconds, countermovement jump of 31.0 (2.9) cm, unilateral countermovement jump of 14.4 (2.1) cm, and quadriceps and hamstring peak torque at 60°·s⁻¹ of 133 (23) and 87 (17) N·m, respectively. Mean scores recorded during in-season were 2% to 22% better than in preseason (effect size: small to very large). Conclusions: This review provides valuable normative physical conditioning and functional injury-risk assessment data for elite female soccer players. Coaches and conditioning staff can use these insights to interpret their own records and optimize their training processes. Furthermore, this study identifies methodological limitations to address in future research.

Background: Adults with physical or intellectual disability are less active than those without disability. Objective: To review literature regarding sport participation in adults with physical or intellectual disability. Specifically, to examine characteristics of available studies including participants, interventions, outcomes, and impact. Methods: A scoping review was completed. Searches of 6 databases and a trial registry plus citation tracking were undertaken. Two independent reviewers screened items for eligibility and extracted data about the studies, participants, interventions, and outcomes. A single reviewer extracted data to quantify impacts of sport participation, classified as favorable, insignificant, or unfavorable. Results: 164 studies involving 11,642 participants were included. Most studies (128/164) used a cross-sectional design. Most participants were men (81%) with physical disability (135/164), and spinal cord injury was the most prevalent underlying health condition (54%). Most studies evaluated a mix of sports (83/164) in a disability-specific context (159/164), with basketball or wheelchair basketball being the most common individual sport (28/164). Physical impairment was the most frequently reported outcome domain (85/334 results). Sports participation impact was classified as 55% favorable, 42% insignificant, and 3% unfavorable. Conclusions: There were many favorable and few unfavorable outcomes for participation in sport for adults with physical or intellectual disability. More research is needed to address the evidence gaps of gender, health condition, and type of sport, and to use more rigorous research designs to evaluate the effects of sport participation. While new evidence is generated, we suggest adults with physical or intellectual disability be encouraged to engage in sport. Registration: PROSPERO registration number CRD42018104379.

Background: The benefits of oral caffeine intake to enhance several aspects of physical performance, such as aerobic endurance, strength, power, and muscle endurance performance, are well supported. However, how the physical performance benefits of caffeine supplementation are translated into better specific actions in intermittent sports during real or simulated competition has been the topic of fewer investigations, and their results need to be appropriately reviewed and meta-analyzed. Objective: The aim of the study was to investigate the effects of acute caffeine intake on specific actions in intermittent sports involving decision making and high-intensity efforts (eg, team, racket, and combat sports) during real or simulated competitions. Methods: All studies included had blinded and crossover experimental designs, and we conducted a risk-of-bias analysis. In total, we included 24 studies. A meta-analysis was performed using the random-effects model to calculate the standardized mean difference (SMD) estimated by Hedges g and 95% CIs. Results: Caffeine ingestion increased high-intensity sport-specific actions during competition, such as the number of sprints (SMD: 0.48; 95% CI, 0.23–0.74), body impacts (SMD: 0.28; 95% CI, 0.08–0.49), accelerations (SMD: 0.35; 95% CI, 0.06–0.63), decelerations (SMD: 0.63; 95% CI, 0.12–1.14), and high-intensity offensive efforts (SMD: 0.36; 95% CI, 0.11–0.61). Additionally, caffeine ingestion induced a higher positive or success rate of actions during real or simulated competition (SMD: 0.44; 95% CI, 0.19–0.69). Conclusion: The current meta-analysis provides evidence of caffeine supplementation in increasing high-intensity efforts and the success rate of sport-specific actions during real or simulated competition.