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Quantifying both external and internal training loads that athletes are exposed to during training sessions is often recommended to assess multifactorial sport-specific demands. Thus, the purpose of the present study was to determine the relationship between a widely used subjective marker of internal load (rate of perceived exertion - RPE) and external load variables obtained from an innovative inertial measurement unit (IMU) device within a cohort of professional male basketball players. Twenty-one athletes competing in the firstand second-tier national basketball leagues in Europe wore an IMU device (i.e., VertTM) during their regular practice session and reported an RPE score (Borg CR-10 scale) immediately post-practice. The findings of this study reveal the presence of a strong significant relationship (r = 0.714) between Stress and RPE. However, weak non-significant relationships (r = 0.198-0.287) were observed between RPE and all jumprelated metrics (Jumps, Jumps 15+, Jumps 20+, Average Jump Height) as well as Active Minutes (r = 0.330), indicating that an increase in internal load is more dependent on the type of activity that players perform rather than the duration of the practice session. Overall, these findings may help sports scientists and strength and conditioning practitioners detect changes in training load throughout a competitive season in male basketball players and ultimately improve the acute and chronic training-adaptation monitoring process. [ABSTRACT FROM AUTHOR]

Team sports require athletes to rapidly reduce whole body momentum and velocity, to efficiently change direction, or to avoid defenders. Decelerations often occur following varying approach distances and velocities. The aim of this study was to investigate the effects of different sprinting approach distances, and therefore velocities and momenta on measures of horizontal deceleration performance within female NCAA Division I softball players. Athletes performed an acceleration:deceleration assessment (ADA) over 20 yards (18.29 m) (ADA20) and 10 yards (9.14 m) (ADA10), respectively. The sample was divided into high and low performance groups for approach velocity and approach momentum, and between-group differences were studied for each test. Correlations between measures of deceleration were analysed between the ADA10 and ADA20. Results suggested that during the ADA20 trials, athletes initiated the deceleration phase at greater approach velocities (p < .001, ES = 2.71) and momenta (p < .001, ES = 2.65), generating greater reductions in velocity (p < .001, ES = 1.60) and momentum (p < .001, ES = 1.50). Within the ADA10, athletes within the high velocity group saw significantly greater reductions in velocity (p = .009, ES = 1.24). This was not observed within the ADA20. A significant negative association was found between average deceleration within the ADA10 and ADA20 (r = -0.443, p = .039). Findings suggest that horizontal decelerations are influenced by the approach distance, velocity, and momentum, which athletes are exposed to before initiating the deceleration phase. This should be accounted for when implementing training to enhance such qualities. [ABSTRACT FROM AUTHOR]

The purpose of the present study was to examine the differences in game-related statistics between home and away games at the NCAA Division-I level of men's basketball competition. The data scraping technique was used to obtain publicly available box scores during the 2018-19 competitive season. Throughout this period, 2181 home and 2205 away box scores were randomly selected across 353 teams, regardless of the winning or losing game outcome. The findings of the present study revealed that the game-related statistics influenced by the game location, listed in descending order of magnitude, were: assists (AS), personal fouls (PF), field-goal percentage (FG%), free-throw attempts (FTA), blocks (BL), defensive rebounds (DRB), turnovers (TO), steals (ST), and three-point shooting percentage (3P%). During home games, the teams tended to display better decision-making processes (i.e., more AS and ST, and less TO), defensive performance (i.e., more DRB and BL), shooting efficiency (i.e., greater FT% and 3P%), and minimize tactical errors (i.e., less PF and more FTA). Overall, these findings suggest that playing on a home-court provides a significant advantage in securing the desired game outcome and provides insight into what game-related statistics contribute most to this effect. [ABSTRACT FROM AUTHOR]

Problem Statement: In the United States, collegiate diving coaches look at two main types of competitions to recruit divers: state high school leagues and club leagues such as USA Diving or the Amateur Athletic Union. It is generally perceived that the judging between these two types of competition is not consistent, but few studies have been conducted to quantify these potential inconsistencies and analyze whether these are individual or systemic biases. Purpose: By comparing equivalent dives from the same diver in both a high school and club diving meet, this study sought to identify judging differences and develop a method for correcting scores between high school and club competitions. Approach: Using all applicable scores across a five-year timespan (2016-2021), including factors such as gender and type of dive, investigators analyzed one-meter springboard diving scores to ascertain if scoring discrepancies exist between club and high school diving competitions. Results: The results revealed statistically significant differences between club and high school net scores for each dive type (all p<0.001), and medium-to-large effect sizes were found for all sub-groups, ranging from 0.577-0.753, except for female reverse dives, which displayed large ES of 0.808. Subsequently, researchers identified correction values to more accurately compare scores between high school and club competitions. Conclusions: Statistical analysis demonstrates significant differences in scoring between club and high school diving scores for all dives and sub-groupings of dives and divers, thus warranting a method for remediating these differences. The corrections developed may provide an initial step towards objectifying scoring within a subjectively scored sport, as well as improving collegiate diving recruitment. [ABSTRACT FROM AUTHOR]

The vertical jump has been widely used in a sport setting for the assessment of lower-body power. Recently, accelerometry has gained popularity as an inexpensive testing modality for assessment of vertical jump performance characteristics. However, accelerometer anatomical placement could affect the accuracy of the data collected. The purpose of this study was to examine the impact of accelerometer placement on assessment of vertical jump performance parameters. Seventeen healthy recreationally active subjects performed three nonconsecutive maximal vertical jumps with no arm swing. Subjects were instructed to keep the hands on the hips and reach 90-degrees internal knee flexion during the eccentric phase of the jumping motion. Two identical accelerometers sampling at 100 Hz were positioned on the abdomen (AB; 5 cm inferior to umbilicus) and on the hip (HP; 5 cm above greater trochanter). Both devices were secured with elastic bands and collected data simultaneously. Ground reaction force curves were computed from the raw accelerometry data from which the following variables were derived: peak concentric force (PCF), peak landing force (PLF), vertical jump height (VJH) based on flight time, and impulse (IMP) excluding subject's body weight. No significant differences were found between AB and HP accelerometer placement for PCF, PLF, and IMP. However, despite a small effect size, HP accelerometer placement resulted in a significantly lower VJH by 1.2 cm. Additionally, strong agreement and consistency of the measurements were observed across all dependent variables examined in the present investigation, suggesting that both AB and HP accelerometer placements may seem appropriate for analysis of vertical jump performance. [ABSTRACT FROM AUTHOR]

The testosterone-to-cortisol ratio (T/C) has been shown to be positively correlated with strength and power. However, few studies have examined the relationship between a standardized power performance measurement and T/C throughout a season of intercollegiate competition. The purpose of this study was to examine the relationships between salivary T/C and vertical jump (VJ) performance of female National Collegiate Athletic Association Division II basketball players across a season. Saliva samples were taken before practice, weekly, for a total of 29 weeks. Samples were assayed for testosterone (T) and cortisol (C). After saliva collection, players completed two countermovement VJs, with the best jump used for data analysis. A positive correlation between T/C and VJ was seen only during the preseason phase. Statistically significant differences were observed across the season for T/C and VJ. T/C in the nonconference phase was significantly lower than the preseason phase and the late-conference phase, p =.013 and p =.047, respectively. VJ was significantly lower in the late-conference phase when compared to the preseason and nonconference phases, p <.001 and p =.026, respectively. VJ in the early-conference phase was also significantly lower than the preseason phase, p <.001. These data support the literature that has indicated a positive relationship between the T/C and lower-body power but only in the preseason phase. This relationship reverses and trends toward a negative relationship, before disappearing in the second half of the season. Monitoring T/C may provide value in assessing female athletes' performance potential in the preseason phase. T/C should be interpreted with more caution once the competitive season begins. [ABSTRACT FROM AUTHOR]

Objective The inappropriate release of free fatty acids from obese adipose tissue stores has detrimental effects on metabolism, but key molecular mechanisms controlling FFA release from adipocytes remain undefined. Although obesity promotes systemic inflammation, we find activation of the inflammation-associated Mitogen Activated Protein kinase ERK occurs specifically in adipose tissues of obese mice, and provide evidence that adipocyte ERK activation may explain exaggerated adipose tissue lipolysis observed in obesity. Methods and Results We provide genetic and pharmacological evidence that inhibition of the MEK/ERK pathway in human adipose tissue, mice, and flies all effectively limit adipocyte lipolysis. In complementary findings, we show that genetic and obesity-mediated activation of ERK enhances lipolysis, whereas adipose tissue specific knock-out of ERK2, the exclusive ERK1/2 protein in adipocytes, dramatically impairs lipolysis in explanted mouse adipose tissue. In addition, acute inhibition of MEK/ERK signaling also decreases lipolysis in adipose tissue and improves insulin sensitivity in obese mice. Mice with decreased rates of adipose tissue lipolysis in vivo caused by either MEK or ATGL pharmacological inhibition were unable to liberate sufficient White Adipose Tissue (WAT) energy stores to fuel thermogenesis from brown fat during a cold temperature challenge. To identify a molecular mechanism controlling these actions, we performed unbiased phosphoproteomic analysis of obese adipose tissue at different time points following acute pharmacological MEK/ERK inhibition. MEK/ERK inhibition decreased levels of adrenergic signaling and caused de-phosphorylation of the β3-adrenergic receptor (β3AR) on serine 247. To define the functional implications of this phosphorylation, we showed that CRISPR/Cas9 engineered cells expressing wild type β3AR exhibited β3AR phosphorylation by ERK2 and enhanced lipolysis, but this was not seen when serine 247 of β3AR was mutated to alanine. Conclusion Taken together, these data suggest that ERK activation in adipocytes and subsequent phosphorylation of the β3AR on S247 are critical regulatory steps in the enhanced adipocyte lipolysis of obesity. [ABSTRACT FROM AUTHOR]