34 research outputs found

    Sex Moderates the Fitness Tests - Performance Index Relationship in Collegiate Basketball: A Case Study

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    Performance indicators are used widely in sports, including basketball. Those total performance metrics are mathematical models that are used to determine the “best” athlete per game/week/season. Players with higher metrics get recruited more and/or get offered better contracts. During offseason, strength and conditioning coaches (SCCs) perform tests to determine the fitness levels of their players. Although those scores differ by sex, the fitness levels are associated with in-season sport performance and, therefore, performance indices. More insight in the fitness tests - performance index relationship in the collegiate basketball and the differential effects by sex would be valuable for all stakeholders (e.g., SCCs, sport coaches, sport agents). In the US, the Player Efficiency Rating (PER) and Efficiency (EFF) are the most commonly used basketball performance indices. PURPOSE: To investigate a) correlation between the uPER and EFF by sex and b) which fitness test most strongly correlates each index by sex. METHODS: Ten male and eight female basketball players (n = 18) from the same college participated. Several fitness tests (full court sprint, bench press, power clean, vertical jump, standing broad jump, and T drill) were performed in the off-season. Performance data, which were collected throughout the following season, were used to calculated unadjusted PER (uPER; equation not shown for space) and EFF (PTS + REB + AST + STL + BLK − Missed FG − Missed FT - TO) / GP). To examine the characteristics of fitness test distributions by sex, the means and standard deviations were generated for each sex. Pearson correlations were estimated as indicators for the relationship between the performance indices and also the relationships between each of the fitness tests and the performance indices by sex. RESULTS: Our results showed lower means and less variability of the fitness tests scores in women than men. The correlation between uPER and EFF in men was moderate (r = .359) and strong in women (r = .662). No strong correlation was found in men between any fitness test and EFF, while full court sprint was strongly correlated with uPER (r = .738). In women, strong correlations were detected between a) T drill and EFF (r = .574) and b) foul court sprint (r = .610), vertical jump (r = .662), and T drill (r = .659) and uPER. No statistical inferences were made due to the nature of the study. CONCLUSION: Our outcomes suggest that uPER and EFF reflect different amounts of information based on sex. Practical implications include that a) foul court drill scores may predict uPER more accurately in both men and women and b) T drill scores may predict both EFF and uPER more precisely in women. Future, larger-scale studies should replicate in other settings with larger samples. Limitations may include small sample size

    Injury Rates in Major League Baseball during the 2020 COVID-19 Season

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    Background: The 2020 Major League Baseball (MLB) season was drastically altered because of the COVID-19 pandemic. The changes included an extended layoff between March and July as well as a shortened preseason. Purpose/Hypothesis: To determine the incidence and epidemiology of MLB injuries in the abbreviated 2020 season compared with prior seasons. We hypothesized that there was an increase in the overall injury rate in the 2020 season compared with the 2018-2019 seasons and that it equally affected all body regions. Study Design: Descriptive epidemiology study. Methods: The MLB transactions database was queried to find players who had been placed on the injury list between 2018 and 2020. Injuries were categorized into upper extremity, lower extremity, spine/core, and other injuries. Incidence per 1000 athlete-exposures was calculated for the prior 2 seasons (2018-2019) and for the 2020 season separately. Incidence for each category was also calculated separately for pitchers and fielders. Incidence rate ratios (IRRs) and confidence intervals were used to compare injury rates in 2018-2019 versus 2020. The z test for proportions was used to determine significant differences between injury incidences. Results: In 2020, the overall incidence rate per 1000 athlete-exposures was almost twice the rate compared with the 2 seasons before COVID-19 (8.66 vs 5.13; IRR, 1.69 [95% CI, 1.53-1.87]; P \u3c .001). Injury incidence increased similarly in 2020 for both pitchers (IRR, 1.68 [95% CI, 1.47-1.91]; P \u3c .001) and fielders (IRR, 1.68 [95% CI, 1.45-1.96]; P \u3c .001). Increases in injury incidence were seen in the upper extremity, spine/core, and other injury categories; however, the incidence of the lower extremity did not change significantly. Conclusion: There was a significant increase in injury incidence for both pitchers and fielders in 2020. Injury rates increased in anatomic zones of the upper extremity and spine/core but were not significantly changed in the lower extremity. The overall increase in injury rate suggests that irregular or insufficient sport-specific preparation prior to the start of the season placed athletes at a greater risk of injury when play resumed

    The Seventh Data Release of the Sloan Digital Sky Survey

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    This paper describes the Seventh Data Release of the Sloan Digital Sky Survey (SDSS), marking the completion of the original goals of the SDSS and the end of the phase known as SDSS-II. It includes 11663 deg^2 of imaging data, with most of the roughly 2000 deg^2 increment over the previous data release lying in regions of low Galactic latitude. The catalog contains five-band photometry for 357 million distinct objects. The survey also includes repeat photometry over 250 deg^2 along the Celestial Equator in the Southern Galactic Cap. A coaddition of these data goes roughly two magnitudes fainter than the main survey. The spectroscopy is now complete over a contiguous area of 7500 deg^2 in the Northern Galactic Cap, closing the gap that was present in previous data releases. There are over 1.6 million spectra in total, including 930,000 galaxies, 120,000 quasars, and 460,000 stars. The data release includes improved stellar photometry at low Galactic latitude. The astrometry has all been recalibrated with the second version of the USNO CCD Astrograph Catalog (UCAC-2), reducing the rms statistical errors at the bright end to 45 milli-arcseconds per coordinate. A systematic error in bright galaxy photometr is less severe than previously reported for the majority of galaxies. Finally, we describe a series of improvements to the spectroscopic reductions, including better flat-fielding and improved wavelength calibration at the blue end, better processing of objects with extremely strong narrow emission lines, and an improved determination of stellar metallicities. (Abridged)Comment: 20 pages, 10 embedded figures. Accepted to ApJS after minor correction

    The Eighth Data Release of the Sloan Digital Sky Survey: First Data from SDSS-III

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    The Sloan Digital Sky Survey (SDSS) started a new phase in August 2008, with new instrumentation and new surveys focused on Galactic structure and chemical evolution, measurements of the baryon oscillation feature in the clustering of galaxies and the quasar Ly alpha forest, and a radial velocity search for planets around ~8000 stars. This paper describes the first data release of SDSS-III (and the eighth counting from the beginning of the SDSS). The release includes five-band imaging of roughly 5200 deg^2 in the Southern Galactic Cap, bringing the total footprint of the SDSS imaging to 14,555 deg^2, or over a third of the Celestial Sphere. All the imaging data have been reprocessed with an improved sky-subtraction algorithm and a final, self-consistent photometric recalibration and flat-field determination. This release also includes all data from the second phase of the Sloan Extension for Galactic Understanding and Evolution (SEGUE-2), consisting of spectroscopy of approximately 118,000 stars at both high and low Galactic latitudes. All the more than half a million stellar spectra obtained with the SDSS spectrograph have been reprocessed through an improved stellar parameters pipeline, which has better determination of metallicity for high metallicity stars.Comment: Astrophysical Journal Supplements, in press (minor updates from submitted version

    The Ninth Data Release of the Sloan Digital Sky Survey: First Spectroscopic Data from the SDSS-III Baryon Oscillation Spectroscopic Survey

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    The Sloan Digital Sky Survey III (SDSS-III) presents the first spectroscopic data from the Baryon Oscillation Spectroscopic Survey (BOSS). This ninth data release (DR9) of the SDSS project includes 535,995 new galaxy spectra (median z=0.52), 102,100 new quasar spectra (median z=2.32), and 90,897 new stellar spectra, along with the data presented in previous data releases. These spectra were obtained with the new BOSS spectrograph and were taken between 2009 December and 2011 July. In addition, the stellar parameters pipeline, which determines radial velocities, surface temperatures, surface gravities, and metallicities of stars, has been updated and refined with improvements in temperature estimates for stars with T_eff<5000 K and in metallicity estimates for stars with [Fe/H]>-0.5. DR9 includes new stellar parameters for all stars presented in DR8, including stars from SDSS-I and II, as well as those observed as part of the SDSS-III Sloan Extension for Galactic Understanding and Exploration-2 (SEGUE-2). The astrometry error introduced in the DR8 imaging catalogs has been corrected in the DR9 data products. The next data release for SDSS-III will be in Summer 2013, which will present the first data from the Apache Point Observatory Galactic Evolution Experiment (APOGEE) along with another year of data from BOSS, followed by the final SDSS-III data release in December 2014.Comment: 9 figures; 2 tables. Submitted to ApJS. DR9 is available at http://www.sdss3.org/dr

    SDSS-III: Massive Spectroscopic Surveys of the Distant Universe, the Milky Way Galaxy, and Extra-Solar Planetary Systems

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    Building on the legacy of the Sloan Digital Sky Survey (SDSS-I and II), SDSS-III is a program of four spectroscopic surveys on three scientific themes: dark energy and cosmological parameters, the history and structure of the Milky Way, and the population of giant planets around other stars. In keeping with SDSS tradition, SDSS-III will provide regular public releases of all its data, beginning with SDSS DR8 (which occurred in Jan 2011). This paper presents an overview of the four SDSS-III surveys. BOSS will measure redshifts of 1.5 million massive galaxies and Lya forest spectra of 150,000 quasars, using the BAO feature of large scale structure to obtain percent-level determinations of the distance scale and Hubble expansion rate at z<0.7 and at z~2.5. SEGUE-2, which is now completed, measured medium-resolution (R=1800) optical spectra of 118,000 stars in a variety of target categories, probing chemical evolution, stellar kinematics and substructure, and the mass profile of the dark matter halo from the solar neighborhood to distances of 100 kpc. APOGEE will obtain high-resolution (R~30,000), high signal-to-noise (S/N>100 per resolution element), H-band (1.51-1.70 micron) spectra of 10^5 evolved, late-type stars, measuring separate abundances for ~15 elements per star and creating the first high-precision spectroscopic survey of all Galactic stellar populations (bulge, bar, disks, halo) with a uniform set of stellar tracers and spectral diagnostics. MARVELS will monitor radial velocities of more than 8000 FGK stars with the sensitivity and cadence (10-40 m/s, ~24 visits per star) needed to detect giant planets with periods up to two years, providing an unprecedented data set for understanding the formation and dynamical evolution of giant planet systems. (Abridged)Comment: Revised to version published in The Astronomical Journa

    Erratum: “The eighth data release of the Sloan Digital Sky Survey: first data from SDSS-III” (2011, ApJS, 193, 29)

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    Section 3.5 of Aihara et al. (2011) described various sources of systematic error in the astrometry of the imaging data of the Sloan Digital Sky Survey (SDSS). In addition to these sources of error, there is an additional and more serious error, which introduces a large systematic shift in the astrometry over a large area around the north celestial pole. The region has irregular boundaries but in places extends as far south as declination δ ≈ 41◦. The sense of the shift is that the positions of all sources in the affected area are offset by roughly 250 mas in a northwest direction. We have updated the SDSS online documentation to reflect these errors, and to provide detailed quality information for each SDSS field

    The Fourteenth Data Release of the Sloan Digital Sky Survey: First Spectroscopic Data from the Extended Baryon Oscillation Spectroscopic Survey and from the Second Phase of the Apache Point Observatory Galactic Evolution Experiment

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    The fourth generation of the Sloan Digital Sky Survey (SDSS-IV) has been in operation since 2014 July. This paper describes the second data release from this phase, and the 14th from SDSS overall (making this Data Release Fourteen or DR14). This release makes the data taken by SDSS-IV in its first two years of operation (2014–2016 July) public. Like all previous SDSS releases, DR14 is cumulative, including the most recent reductions and calibrations of all data taken by SDSS since the first phase began operations in 2000. New in DR14 is the first public release of data from the extended Baryon Oscillation Spectroscopic Survey; the first data from the second phase of the Apache Point Observatory (APO) Galactic Evolution Experiment (APOGEE-2), including stellar parameter estimates from an innovative data-driven machine-learning algorithm known as "The Cannon"; and almost twice as many data cubes from the Mapping Nearby Galaxies at APO (MaNGA) survey as were in the previous release (N = 2812 in total). This paper describes the location and format of the publicly available data from the SDSS-IV surveys. We provide references to the important technical papers describing how these data have been taken (both targeting and observation details) and processed for scientific use. The SDSS web site (www.sdss.org) has been updated for this release and provides links to data downloads, as well as tutorials and examples of data use. SDSS-IV is planning to continue to collect astronomical data until 2020 and will be followed by SDSS-V

    Effect of Last Meal Timing on Sleep Efficiency in College Students during COVID-19

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    Sleep efficiency (SE), the proportion of total sleep time to total time spent in bed, has established associations with various health and disease outcomes. Notably, the interval time between the last meal and bedtime has been shown to influence SE. Recent studies indicate that the COVID-19 pandemic has resulted in significant disruptions to the eating and sleeping patterns of college students. PURPOSE: To explore changes in college students’ SE in relation to the timing of their last meal and bedtime during COVID-19. METHODS: We collected data from 123 college students (mage = 19.3 years, SD = 0.97; 58 Females, 65 Males) over 66 days. Self-reported questionnaires were used to obtain the interval time (IT) between the last meal and bedtime (calculated as the difference in minutes). Growth curve mixed modeling (GAMLj) with 2990 observations was used to analyze the data, treating waves (i.e., days), sex, and IT as latent variables. RESULTS: SE varied between 0.02% and 1%, while IT ranged from 15 to 1380 minutes. The intercept (β = 0.92) represents the predicted SE for students on day 1. The slope for waves was positive and significant (β = 0.001, p \u3c 0.001). Conversely, the slope for IT was negative and significant (β = -0.001, p = 0.003). The level 2 predictor, sex, was also significant and negative (β = -0.05, p = 0.001) (Female = 0, Male = 1). The variation in intercepts, representing day 1 SE for each student, was significant (σm 2 = .01, LR χ²(1) = 1117.77, p \u3c.001), with an ICC of 0.36. No significant interaction effects were observed among the examined variables. CONCLUSION: This study provides valuable insights into the relationship between meal timing habits and SE during a stressful period amidst COVID-19. The findings suggest that SE is predicted to increase gradually over time, but decrease with longer intervals between the last mealtime and bedtime. Additionally, females exhibited higher SE compared to males, and substantial between-student variation in day 1 SE was observed. These results can inform interventions aimed at improving SE in young adults, particularly during times of increased stress. Limitations include self-reported measures. Future studies should account for other potential factors that may influence SE, such as physical activity and caffeine intake
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