Lim, C, Wee, J, Lee, M, Lim, S, and Leow, S. Validity and reliability of the power slap board as an application to measure upper body vertical pulling power for female water polo players. J Strength Cond Res 38(11): e670-e677, 2024-This study examined the validity and reliability of the power slap test (PS) as an assessment for upper body pulling power to predict water polo functional performance and competitive experience of female water polo players. Seventeen female water polo players from the national and development squads were recruited. Subjects completed test-retest sessions of PS testing and 1 session of functional performance tests for the 15-m arms-only sprint (15 mAOS) and the 5-m maximum shooting velocity (5 mMSV). All PS, 15 mAOS and 5 mMSV results were compared for predictability. Power slap scores demonstrated high reliability for left PS (intraclass correlations [ICC]: 0.96, 90% confidence interval [CI]: 0.91-0.98), right PS (ICC: 0.96, 90% CI: 0.90-0.98), left and right center of mass (COM) displacement (ICC: 0.98, 90% CI: 0.96-0.99; ICC: 0.95, 90% CI: 0.88-0.98), and summed PS (ICC: 0.96, 90% CI: 0.92-0.99). All absolute PS scores and left COM displacement (COMdispL) demonstrated large correlations with the 15 mAOS times (r = -0.542 to -0.52, r(2) = 0.27-0.29, p < 0.05). No performance parameters of the PS were correlated with the 5 mMSV performance (p > 0.05). This study validates the reliability of the PS as a dryland assessment tool for upper body pulling power. Only absolute PS scores and COMdisp were validated as weak predictors of the arms-only sprint times over 15 m. Its predictive power significantly improved when considered in combination with shooting performance. All absolute and normalized kinetic and kinematic PS parameters did not predict functional performance and competitive experience.

Pharmacological agents used to treat or manage diseases can modify the level of heat strain experienced by chronically ill and elderly patients via different mechanistic pathways. Human thermoregulation is a crucial homeostatic process that maintains body temperature within a narrow range during heat stress through dry (i.e., increasing skin blood flow) and evaporative (i.e., sweating) heat loss, as well as active inhibition of thermogenesis, which is crucial to avoid overheating. Medications can independently and synergistically interact with aging and chronic disease to alter homeostatic responses to rising body temperature during heat stress. This review focuses on the physiologic changes, with specific emphasis on thermolytic processes, associated with medication use during heat stress. The review begins by providing readers with a background of the global chronic disease burden. Human thermoregulation and aging effects are then summarized to give an understanding of the unique physiologic changes faced by older adults. The effects of common chronic diseases on temperature regulation are outlined in the main sections. Physiologic impacts of common medications used to treat these diseases are reviewed in detail, with emphasis on the mechanisms by which these medications alter thermolysis during heat stress. The review concludes by providing perspectives on the need to understand the effects of medication use in hot environments, as well as a summary table of all clinical considerations and research needs of the medications included in this review. Significance Statement Long-term medications modulate thermoregulatory function, resulting in excess physiological strain and predisposing patients to adverse health outcomes during prolonged exposures to extreme heat during rest and physical work (e.g., exercise). Understanding the medication-specific mechanisms of altered thermoregulation has importance in both clinical and research settings, paving the way for work toward refining current medication prescription recommendations and formulating mitigation strategies for adverse drug effects in the heat in chronically ill patients.

BACKGROUND:Identifying key variables that predict sleep quality in youth athletes allows practitioners to monitor the most parsimonious set of variables that can improve athlete buy-in and compliance for athlete self-report measurement. Translating these findings into a decision-making tool could facilitate practitioner willingness to monitor sleep in athletes.HYPOTHESIS:Key predictor variables, identified by feature reduction techniques, will lead to higher predictive accuracy in determining youth athletes with poor sleep quality.STUDY DESIGN:Cross-sectional study.LEVEL OF EVIDENCE:Level 3.METHODS:A group (N = 115) of elite youth athletes completed questionnaires consisting of the Pittsburgh Sleep Quality Index and questions on sport participation, training, sleep environment, and sleep hygiene habits. A least absolute shrinkage and selection operator regression model was used for feature reduction and to select factors to train a feature-reduced sleep quality classification model. These were compared with a classification model utilizing the full feature set.RESULTS:Sport type, training before 8 am, training hours per week, presleep computer usage, presleep texting or calling, prebedtime reading, and during-sleep time checks on digital devices were identified as variables of greatest influence on sleep quality and used for the reduced feature set modeling. The reduced feature set model performed better (area under the curve, 0.80; sensitivity, 0.57; specificity, 0.80) than the full feature set models in classifying youth athlete sleep quality.CONCLUSION:The findings of our study highlight that sleep quality of elite youth athletes is best predicted by specific sport participation, training, and sleep hygiene habits.CLINICAL RELEVANCE:Education and interventions around the training and sleep hygiene factors that were identified to most influence the sleep quality of youth athletes could be prioritized to optimize their sleep characteristics. The developed sleep quality nomogram may be useful as a decision-making tool to improve sleep monitoring practice among practitioners.

Purpose This study examined the effects of tournament load on neuromuscular function, perceived wellness and coach ratings of performance across two 6-day netball tournaments. Methods Thirty-nine female youth netballers (age = 14.6 ± 0.5 years, stature = 165.9 ± 4.7 cm, body mass = 56.5 ± 7.2 kg) were categorised as HIGH (10–11 matches, n = 20) or LOW (6 matches, n = 19) tournament load. Match load, jump height, perceived wellness and coach ratings of performance were monitored daily. Results HIGH tournament load resulted in greater reductions in jump height on match-day 4 (–8.3%, ± 5.6%) when compared to LOW. HIGH tournament load resulted in greater reductions in perceived soreness (–0.9, ± 1.1 AU) and overall wellness (–2.6, ± 2.3 AU) on match-day 3, and a greater reduction in perceived sleep (–0.9, ± 1.1 AU) on match-day 4. HIGH tournament load was negatively associated with sleep quality and coach ratings of performance (effect size correlation = -0.34 to -0.47) when compared to LOW. Conclusion Our results indicate that a higher tournament load resulted in greater increases in neuromuscular fatigue, reduced perceived wellness, and lower ratings of performance. Practitioners should consider pre-tournament preparation and monitoring strategies to minimise the physiological disturbances during an intensified tournament.

PURPOSE:Elite athletes experience chronic sleep insufficiency due to training and competition schedules. However, there is little research on sleep and caffeine use of elite youth athletes and a need for a more nuanced understanding of their sleep difficulties. This study aimed to (1) examine the differences in sleep characteristics of elite youth athletes by individual and team sports, (2) study the associations between behavioral risk factors associated with obstructive sleep apnea and caffeine use with sleep quality, and (3) characterize the latent sleep profiles of elite youth athletes to optimize the sleep support strategy. METHODS:A group (N = 135) of elite national youth athletes completed a self-administered questionnaire consisting of the Pittsburgh Sleep Quality Index (PSQI) and questions pertaining to obstructive sleep apnea, napping behavior, and caffeine use. K-means clustering was used to characterize unique sleep characteristic subgroups based on PSQI components. RESULTS:Athletes reported 7.0 (SD = 1.2) hours of sleep. Out of the total group, 45.2% of the athletes had poor quality sleep (PSQI global >5), with team-sport athletes reporting significantly poorer sleep quality than individual-sport athletes. Multiple logistic regression analysis indicated that sport type significantly correlated with poor sleep quality. The K-means clustering algorithm classified athletes' underlying sleep characteristics into 4 clusters to efficiently identify athletes with similar underlying sleep issues to enhance interventional strategies. CONCLUSION:These findings suggest that elite youth team-sport athletes are more susceptible to poorer sleep quality than individual-sport athletes. Clustering methods can help practitioners characterize sleep-related problems and develop efficient athlete support strategies.

Using palatable fluids to enhance drinking in athletes who display insufficient compensatory hydration behaviour may mitigate the risks of hypohydration and performance deficits. However, it is unclear whether flavour can independently enhance fluid consumption. This study examined the effects of a colourless, artificially sweetened flavoured water (FW), without carbohydrates and with negligible amounts of sodium, compared to plain water (W) on fluid consumption in male collegiate basketball players in a practical game setting. Eighteen male basketball players (age 23.1 ± 1.3 years) played a 3v3 basketball small-sided game. The players were randomly assigned to consume either FW or W. Pre-game urine-specific gravity, fluid consumption, body mass, and hedonic taste perceptions were assessed. Basketball performance was analysed through notational analysis. Ratings of perceived exertion and thirst were recorded at pre-, post-game, and at each rest period. Heart rate was recorded throughout the gameplay. Despite significantly higher hedonic ratings for FW than W (6.78 ± 0.83 vs. 5.56 ± 1.33, p = 0.033, d = 1.36), there were no significant differences in fluid consumption (1083 ± 32 mL vs. 1421 ± 403 mL, p = 0.068, d = 0.92). Our result highlighted that using palatable fluids as a strategy to increase fluid consumption during high-intensity gameplay in the heat may not be effective if used without carbohydrates and electrolytes. Practitioners could consider both fluid palatability and composition in establishing a hydration plan for athletes.

There are limited data on the fluid balance characteristics and fluid replenishment behaviors of high-performance adolescent athletes. The heterogeneity of hydration status and practices of adolescent athletes warrant efficient approaches to individualizing hydration strategies. This study aimed to evaluate and characterize the hydration status and fluid balance characteristics of high-performance adolescent athletes and examine the differences in fluid consumption behaviors during training. In total, 105 high-performance adolescent athletes (male: 66, female: 39; age 14.1 ± 1.0 y) across 11 sports had their hydration status assessed on three separate occasions—upon rising and before a low and a high-intensity training session (pre-training). The results showed that 20–44% of athletes were identified as hypohydrated, with 21–44% and 15–34% of athletes commencing low- and high-intensity training in a hypohydrated state, respectively. Linear mixed model (LMM) analyses revealed that athletes who were hypohydrated consumed more fluid (F (1.183.85)) = 5.91, (p = 0.016). Additional K-means cluster analyses performed highlighted three clusters: “Heavy sweaters with sufficient compensatory hydration habits,” “Heavy sweaters with insufficient compensatory hydration habits” and “Light sweaters with sufficient compensatory hydration habits”. Our results highlight that high-performance adolescent athletes with ad libitum drinking have compensatory mechanisms to replenish fluids lost from training. The approach to distinguish athletes by hydration characteristics could assist practitioners in prioritizing future hydration intervention protocols.