bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Effect of Stirrup Length on Impact Attenuation and Its Association With Muscle Strength
Authors: Keener Michaela M. , Critchley Meghan L. , Layer Jacob S. , Johnson Evan C. , Barrett Steven F. , Dai Boyi 
Published: January 2020

Abstract
Keener, MM, Critchley, ML, Layer, JS, Johnson, EC, Barrett, SF, and Dai, B. The effect of stirrup length on impact attenuation and its association with muscle strength. J Strength Cond Res 35(11): 3056–3062, 2021—Horseback-riders have a high prevalence of low back injuries, which may be related to the repetitive low back impacts experienced in riding. The purposes of this study were to quantify the effect of 3 stirrup lengths and 2 riding styles on the peak acceleration experienced by the rider and the association between the peak acceleration and the rider's different elements of muscle strength. Thirteen female riders performed a sitting or rising trot at each of the 3 stirrup lengths (2-point length, mid-seat length, or dressage length), while the acceleration of the tibia, sacrum, seventh cervical vertebra (C7), and head were collected. Subjects completed a push-up, a vertical jump, and 4 core exercises to assess upper-body strength, lower-body strength, and core endurance, respectively. Peak acceleration of the sacrum, C7, and head were generally lower in the standing phase of the rising trot compared with the sitting phase of either the sitting or rising trot, particularly at the shortest stirrup length. Peak acceleration of the sacrum, C7, and head decreased as the stirrup length was shortened in the standing phase of the rising trot. Canonical correlations showed nonsignificant correlations between strength measurements and peak acceleration. Riding with more weight supported through the legs with a short stirrup length may decrease low back impacts and their associated injury risk. Technique training is likely needed to encourage riders to use lower-body and core strength for impact attenuation.
Validity and Reliability of a Standardized Protocol for Assessing the One Repetition Maximum Performance During Overhead Pressing Exercises
Authors: Soriano Marcos A. , García-Ramos Amador , Torres-González Antonio , Castillo-Palencia Joaquín , Ayuso Víctor , Marín Pedro J. , Comfort Paul 
Published: January 2020

Abstract
Soriano, MA, García-Ramos, A, Torres-González, A, Castillo-Palencia, J, Ayuso, V, Marín, PJ, and Comfort, P. Validity and reliability of a standardized protocol for assessing the one repetition maximum performance during overhead pressing exercises. J Strength Cond Res 35(11): 2988–2992, 2021—The aim of this study was to determine the validity of performing 3 one repetition maximum (1RM) assessments for the push press (PP), push jerk (PJ), and split jerk (SJ) in sequence in one testing session vs. the criterion method (testing on separate days), while determining the between-session reliability of the combined assessment. Twenty-two well-trained men (n = 22; age: 28.5 + 1.3 years; height: 1.80 + 0.04 m; body mass: 84.9 + 1.9 kg; training experience: 4.27 + 4.08 years) participated in this study. The 1RM was assessed in a sequential order in the same testing session (combined 1RM assessment) for the PP, PJ, and SJ on 2 occasions, to determine between-session reliability. The 1RM for each exercise was also examined on 3 separate sessions to compare the results against the combined method. A high reliability, low variability, and low measurement error were evident for the PP (intraclass correlation coefficient [ICC] = 0.960; coefficient of variation [CV] = 1.8%; smallest detectable difference [SDD] = 7.1%), PJ (ICC = 0.978; CV = 1.5%; SDD = 5.4%) and SJ (ICC = 0.987; CV = 0.8%; SDD = 4.6%). In addition, there were no significant (p > 0.05) or meaningful (η2 ≤0.001) differences between the single and combined assessments. The high reliability and validity of the combined assessment suggest that practitioners and researchers may simplify the testing procedure by assessing the 1RM during the 3 main overhead pressing exercises in a single testing session.
Seasonal Change in Body Composition and Physique of Team Sport Athletes
Authors: Walker Emily J. , Aughey Robert J. , McLaughlin Patrick , McAinch Andrew J. 
Published: January 2020

Abstract
Walker, EJ, Aughey, RJ, McLaughlin, P, and McAinch, AJ. Seasonal change in body composition and physique of team sport athletes. J Strength Cond Res 36(2): 565–572, 2022—Body composition of team sport athletes was measured at 3 points across the preseason and competitive season. This repeated-measures study was conducted in 46 professional Australian football (AF) (age 23.8 ± 3.8 years), 26 soccer (age 22.7 ± 4.7 years), and 33 rugby union players (age 28.1 ± 4.2 years). A mixed-design analysis of variance was used to determine change across the season, and Pearson's correlation was used to determine the relationship between different measures. Anthropometry, dual-energy x-ray absorptiometry (DXA), and 3-dimensional (3D) scan technology were used in AF and soccer, whereas only DXA was used in rugby. Body mass remained unchanged for both AF and soccer with gains in lean mass (p < 0.01), from preseason to early in the competitive season. Skinfold measures declined in AF (p < 0.001) and soccer (p < 0.05) across the season, whereas DXA-measured fat mass only declined in soccer (p < 0.01). Rugby backs (p < 0.01) and forwards (p < 0.001) reduced body fat and gained lean mass from preseason to in-season with forwards having greater relative and absolute changes as measured by DXA. 3D technology did not show change across the season. Dual-energy x-ray absorptiometry body fat percent and the sum of skinfold correlation were large (r = 0.74 [p < 0.001, CI 0.67–0.81]). The greatest change in body composition occurs from the beginning of preseason to the start of competition, with changes returning to baseline levels toward the end of season. Dual-energy x-ray absorptiometry and skinfold measures were moderately correlated, providing a good alternative to track change in subcutaneous fat in AF and soccer athletes.
Comparison of Internal and External Training Loads in Male and Female Collegiate Soccer Players During Practices vs. Games
Authors: McFadden Bridget A. , Walker Alan J. , Bozzini Brittany N. , Sanders David J. , Arent Shawn M. 
Published: January 2020

Abstract
McFadden, BA, Walker, AJ, Bozzini, BN, Sanders, DJ, and Arent, SM. Comparison of internal and external training loads in male and female collegiate soccer players during practices vs. games. J Strength Cond Res 34(4): 969–974, 2020—The purpose of this study was to compare the internal and external training loads (TLs) in men and women throughout a Division I soccer season during practices versus games. Players were evaluated during all practices and regulation game play using the Polar TeamPro system, utilizing Global Positioning Satellite technology and heart rate (HR) monitoring to determine TL, time spent in HR zones expressed as a percent of HRmax (HRZ1–Z5), calories expended per kilogram body mass (Kcal·kg−1), distance covered (DIS), sprints, average speed (SPDAVG), and distance covered in speed zones (DISZ1–Z5). During games, no significant differences were seen between men and women for TL, Kcal·kg−1, HRZ1–Z5, SPDAVG, DIS, DISZ1, DISZ3, and DISZ4. However, men accumulated a significantly greater number of sprints and DISZ5 (p < 0.05) during games, whereas women accumulated a greater DISZ2 (p < 0.05). During practice, no differences were observed for TL, DIS, sprints, Kcal·kg−1, DISZ2, DISZ3, HRZ1–Z5, but men exhibited higher SPDAVG, (p < 0.05), DISZ1 (p < 0.05), DISZ4 (p < 0.05), and DISZ5 (p < 0.05). The parallels in Kcal·kg−1, total DIS, HR, and TL indicate a similar relative workload between men and women. However, distance covered in higher speed zones was found to be greater in men than women across practice and games likely reflecting inherent sex differences in the ability to achieve those speeds. Monitoring techniques that track relative player workloads throughout practices and games may enhance player health and performance during the season. An individualized approach to tracking high-intensity running may improve workload prescriptions on a per player basis.
Early Season Hormonal and Biochemical Changes in Division I Field Hockey Players: Is Fitness Protective?
Authors: Walker Alan J. , McFadden Bridget A. , Sanders David J. , Bozzini Brittany N. , Conway Sean P. , Arent Shawn M. 
Published: January 2020

Abstract
Walker, AJ, McFadden, BA, Sanders, DJ, Bozzini, BN, Conway, SP, and Arent, SM. Early season hormonal and biochemical changes in Division I field hockey players: is fitness protective? J Strength Cond Res 34(4): 975–981, 2020—The purpose was to evaluate changes in hormonal and biochemical markers as a result of the accumulated stress of the initial 4-week training block in field hockey players. Women's Division I field hockey players (N = 22; Mage = 19.7 ± 1.1 years) performed testing before the start of preseason (A1) that included body composition (%BF), vertical jump, and V̇o
2max. Blood draws were conducted at A1 to assess creatine kinase (CK), iron (Fe), hemoglobin (HGB), hematocrit (HCT), percent saturation (%sat), total cortisol (TCORT), free cortisol (FCORT), interleukin-6 (IL-6), sex hormone–binding globulin (SHBG), prolactin (PRL), vitamin D (vitD), and thyroxine (T3). Blood draws were repeated 4 weeks later (A2). Athletes were monitored during this training block, which included 2 weeks of preseason and the first 2 weeks of the season, using heart rate monitors to determine energy expenditure (Kcal) and training load. There were significant disruptions in TCORT, FCORT, T3, CK, Fe, and SHBG (p < 0.05) from A1 to A2. V̇o
2max accounted for 31% (p < 0.05) of the variance in TCORT and %BF accounting for an additional 20.1% (p < 0.05). V̇o
2max accounted for 32.7% (p < 0.05) of the variance in FCORT. %BF accounted for 48.9% (p < 0.05) of the variance in T3. Kcal was positively correlated with V̇o
2max (p < 0.05) and negatively correlated with %BF (p < 0.05). Athletes with higher V̇o
2max and lower %BF may be capable of a higher work output and therefore more likely to experience increased physiological disruptions during intense training. The high-volume nature of preseason and differences in athlete fitness capabilities require coaches to manage players at an individual level to maintain athlete readiness.
Postactivation Potentiation in Blood Flow–Restricted Complex Training
Authors: Cleary Christopher J. , Cook Summer B. 
Published: January 2020

Abstract
Cleary, CJ and Cook, SB. Postactivation potentiation in blood flow–restricted complex training. J Strength Cond Res 34(4): 905–910, 2020—Complex training uses a high-load (HL) resistance exercise to elicit postactivation potentiation (PAP) that is typically observed through enhanced plyometric performance. Blood flow–restricted (BFR) resistance exercise uses low loads to induce similar muscular adaptations to HL resistance exercise; however, the efficacy and feasibility of BFR complex training are unknown. Fifteen college-aged men (mean ± SD; age: 20.3 ± 0.9 years; relative back-squat one-repetition maximum [1RM]: 1.78 ± 0.3 kg·kg−1) with at least 2 years of resistance training experience completed 3 sessions: a familiarization session with 1RM testing, and 2 complex training sessions of 3 presquat vertical jumps (VJs), condition-specific back squats (HL: 5 repetitions at 85% 1RM, BFR: 30 repetitions at 30% 1RM), and a single postsquat VJ. Postactivation potentiation was calculated as (postsquat VJ height ÷ max presquat VJ height) ∙ 100. Electromyography (EMG) of the vastus lateralis and hamstrings was collected, quantified to root mean square values, and normalized to peak 1RM activity. Postsquat VJ height was significantly reduced in both conditions, and PAP did not occur because it was less than 100% (HL: 96.1 ± 5.1%, BFR: 90.8 ± 7.8%, p = 0.010). Vastus lateralis and hamstrings EMG amplitude was highest (p < 0.001) in the HL condition. High-load and BFR complex training decreased subsequent VJ height in these individuals, and this might have been due to an ineffective complex training protocol and individual factors such as training status and relative strength.
Monitoring Internal Training Load, Stress-Recovery Responses, and Immune-Endocrine Parameters in Brazilian Jiu-Jitsu Training
Authors: Campos Flavia , Molina Correa Júlio C. , Canevari Vinicius C.M. , Branco Braulio H.M. , Andreato Leonardo V. , de Paula Ramos Solange 
Published: January 2020

Abstract
Campos, F, Molina Correa, JC, Canevari, VCM, Branco, BHM, Andreato, LV, and de Paula Ramos, S. Monitoring internal training load, stress-recovery responses, and immune-endocrine parameters in Brazilian jiu-jitsu training. J Strength Cond Res 36(3): 723–731, 2022—This study aimed to evaluate the relationship between training loads, stress, and immune-endocrine markers during a precompetitive period in Brazilian jiu-jitsu (BJJ) athletes. For this, 12 athletes were submitted to 1 physical and 1 technical-tactical training session per day, 5 days a week, for 7 weeks. The saliva sampling and physical tests (countermovement jump [CMJ] and squat jump [SJ]) were performed before starting the training period (pre) and at the fourth week (4-week) and eighth week (post). Session rating of perceived exertion (sRPE) and the Recovery-Stress Questionnaire–Sport (RESTQ) were applied, and the training load was calculated weekly. Repeated-measures analysis of variance and the Friedman test were used, with significance levels set at p < 0.05. Increased training loads were recorded by the sRPE method in technical-tactical training sessions (p < 0.05). Higher physical loads were reported by athletes during weeks 1–4, contributing to overall higher training load, monotony, and strain during this period (p < 0.05). Increased perception of stress, by the RESTQ, and cortisol were detected, whereas decreased salivary testosterone and salivary immunoglobulin A were observed at 4 weeks (p < 0.05). No significant differences were detected in CMJ and SJ tests, suggesting that training neither elicited significant fatigue and underperformance nor improved strength performance. However, decreasing physical training loads appeared to reduce symptoms of stress and improved recovery, favoring immune recovery and anabolic balance. Thus, the sRPE seems to be a reliable and simple method to monitor training loads in BJJ athletes because variation in values was related to the RESTQ and physiological responses to training loads.
Volleyball-Specific Skills and Cognitive Functions Can Discriminate Players of Different Competitive Levels
Authors: Formenti Damiano , Trecroci Athos , Duca Marco , Vanoni Marta , Ciovati Miriam , Rossi Alessio , Alberti Giampietro 
Published: January 2020

Abstract
Formenti, D, Trecroci, A, Duca, M, Vanoni, M, Ciovati, M, Rossi, A, and Alberti, G. Volleyball-specific skills and cognitive functions can discriminate players of different competitive levels. J Strength Cond Res 36(3): 813–819, 2022—The aim of this study was to investigate whether volleyball-specific skills, physical performance, and general cognitive functions differ between players of different competitive levels. Twenty-six female volleyball players competing at 2 different levels (n = 13, regional; n = 13, provincial) were tested on volleyball-specific skills (accuracy and technique of setting, passing, spiking, and serving), change of direction speed (COD) by the modified T-test, countermovement jump (CMJ) and general cognitive functions (executive control by Flanker task and perceptual speed by visual search task). Four machine learning models were tested to detect the best one to predict players' level. Regional players presented higher passing, spiking, serving accuracy (p < 0.05) and setting, passing, spiking, and serving technique (p < 0.05) than provincial players. Regional players had also better performance in COD and CMJ than provincial players (p < 0.05). Regional players presented lower response time than provincial players in both congruent and incongruent conditions of the Flanker task, and in both 10 items and 15 items conditions of the visual search task (p < 0.05). Decision tree classifier was the machine learning model with the highest performance to discriminate regional and provincial players (93% precision and 73% recall) by considering passing technique, congruent and incongruent condition of the Flanker task, 15 items and 10 items condition of the visual search task, and spiking technique. These findings demonstrated the importance of assessing volleyball-specific skills and cognitive functions as playing a role to discriminate players of different competitive levels.
Recruit Fitness Standards From a Large Law Enforcement Agency: Between-Class Comparisons, Percentile Rankings, and Implications for Physical Training
Authors: Lockie Robert G. , Dawes J. Jay , Orr Robin M. , Dulla Joseph M. 
Published: January 2020

Abstract
Lockie, RG, Dawes, JJ, Orr, RM, and Dulla, JM. Recruit fitness standards from a large law enforcement agency: Between-class comparisons, percentile rankings, and implications for physical training. J Strength Cond Res 34(4): 934–941, 2020—Law enforcement can be a physically demanding profession. Many agencies use a “one-size-fits-all” academy training approach, which may not be optimal for all recruits. There is also little information that benchmarks fitness of law enforcement recruits. The purpose of this study was to analyze between-academy class differences in fitness, as well as produce normative data for the development of strength and conditioning programs. A retrospective analysis of 908 recruits (761 men and 147 women), comprising 11 classes from one agency, was used. Fitness assessment data included push-ups, sit-ups, and mountain climbers in 120 seconds; pull-ups; 201-m run; and 2.4-km run. A one-way analysis of variance with a Bonferroni post hoc adjustment revealed that fitness varied significantly between classes. Class 11 completed less sit-ups than 6 other classes (p ≤ 0.033) and were slower in the 201-m and 2.4-km run than 5 classes (p ≤ 0.005). Class 7 completed less push-ups than 3 classes (p ≤ 0.036) and less mountain climbers and were slower in the 201-m run than 5 classes (p ≤ 0.005). Individual recruit analysis and percentile data indicated a wide spread of all assessment results and the effects upon female recruits. For example, 81% of women completed ≤2 pull-ups and were in the bottom 2 percentile bands; 72–76% of women were in the bottom 3 bands for push-ups and the 201-m run. Fitness varies from class-to-class, and female recruits will generally be less physically fit. Training staff should ideally implement individualized, ability-based programming where appropriate to train their recruits.
Genetic Basis of Increased Lifespan and Postponed Senescence inDrosophila melanogaster
Authors: Parker Grace A , Kohn Nathan , Spirina Ally , McMillen Anna , Huang Wen , Mackay Trudy F C 
Published: January 2020

AbstractLimited lifespan and senescence are near-universal phenomena. These quantitative traits exhibit variation in natural populations due to the segregation of many interacting loci and from environmental effects. Due to the complexity of the genetic control of lifespan and senescence, our understanding of the genetic basis of variation in these traits is incomplete. Here, we analyzed the pattern of genetic divergence between long-lived (O) Drosophila melanogaster lines selected for postponed reproductive senescence and unselected control (B) lines. We quantified the productivity of the O and B lines and found that reproductive senescence is maternally controlled. We therefore chose 57 candidate genes that are expressed in ovaries, 49 of which have human orthologs, and assessed the effects of RNA interference in ovaries and accessary glands on lifespan and reproduction. All but one candidate gene affected at least one life history trait in one sex or productivity week. In addition, 23 genes had antagonistic pleiotropic effects on lifespan and productivity. Identifying evolutionarily conserved genes affecting increased lifespan and delayed reproductive senescence is the first step toward understanding the evolutionary forces that maintain segregating variation at these loci in nature and may provide potential targets for therapeutic intervention to delay senescence while increasing lifespan.
Diagnostic and prognostic value of microRNAs for Alzheimer’s disease: a comprehensive meta-analysis
Authors: Cătană Cristina-Sorina , Crișan Cătălina-Angela , Opre Dana , Berindan-Neagoe Ioana 
Published: January 2020

Background and aims. Recent research has shown that microRNAs (miRNAs), a class of sequences regulating gene expression without undergoing translational processes, have been accepted as novel biomarkers of diseases. In the present meta-analysis, our main objective was to evaluate the diagnostic value of miRNAs expressed in different body fluids for AD, more exactly to analyze the discriminative value of miRNAs between AD and control subjects.
Methods. Medline and EMBASE were searched for articles written in English language and because the result reporting modalities were extremely different in the studies included in the analysis, the current article comprises 2 meta-analysis studies, each of them using different statistical indicators. The first meta-analysis reviewed 10 studies, which were required to provide sufficient information to allow the calculation of AUC or Cohen’s d for size effect. We proposed a second meta-analysis, starting from the drawbacks identified in this first approach, which used different statistical indicators (fold change) provided by other studies (8 studies).
Results. The present study offers an encouraging role of miRNA families in diagnosing AD. The heterogeneity of miRNA expression between the hippocampus, CSF and peripheral blood, the small sample size of each research study, as well as the different methods for miRNA detection remain the main obstacles in interpreting these results.
Conclusions.There is a need (in a future perspective) to establish the right miRNA combinations as potent diagnostic biomarkers for AD.
Protein és glikán biomarkerek szerepe a krónikus obstruktív tüdőbetegség diagnosztikájában
Authors: Szabó Miklós , Kun Renáta , Hajba László , Koncz Roland , Guttman András , Csánky Eszter 
Published: January 2020

Absztrakt:
A krónikus obstruktív tüdőbetegség (COPD) világszerte előkelő helyet foglal el a
morbiditási és mortalitási statisztikákban. A COPD megelőzhető és kezelhető
betegség, kialakulásáért döntően a dohányzás tehető felelőssé. A prevenció
kulcsfontosságú, de korlátozottan kivitelezhető, így a rizikó meghatározása és a
korai noninvazív diagnosztika révén lehetne tovább csökkenteni a COPD miatti
halálozást. A fejlődő diagnosztikus technikák ellenére az optimális
szűrővizsgálat felfedezése még várat magára. Kellően szenzitív és specifikus
biomarkerek felfedezése megfelelő eszközt adhat a klinikus kezébe a betegség
korai diagnosztizálásához, a differenciáldiagnosztikához, a fenotipizáláshoz és
a prognózis becsléséhez. Közleményünkben a COPD vonatkozásában a közelmúltban
felfedezett potenciális fehérje és glikán biomarkereket foglaljuk össze. Orv
Hetil. 2020; 161(4): 123–128.