bluuebunny/crossref_metadata_2025 huggingface dataset:
Michał Kazimierz Radziwiłł „Rybeńko” jako uczeń
Authors: Kucharski Adam
Published: July 2024

Michał Kazimierz Radziwiłł, nicknamed “Rybeńko” (1702–1762), was a prominent representative of a Lithuanian–Polish magnate family in the 18th century. However, researchers have yet to portray his activities as a learner and a respective study is in high demand. A wealth of preserved historical sources: a journal and letters, allow to learn more and describe the course of his studies. The young magnate received only home education and went on a youthful educational journey (a grand tour), like many of his magnate peers. What emerges from the autobiographical notes is a picture of the learning process and relationships with the teachers. However, the skills he acquired and the average level of education did not have a profound impact on his political and military career, which was made possible by his social background.
Ze Wschowy do Strasburga przez Bazyleę – przypadki edukacyjne Jana Jakuba Doldego (1717–1789)
Authors: Tomczak Robert T.
Published: July 2024

Johann Jacob Dolde (1717–1789) was a poor son of a barber from a small border town of Wschowa. From an early age, however, he longed to become a trained doctor of medicine. In order to achieve his goal, as an adolescent, he travelled abroad in order to receive proper education. His journey of several years took him through Poland, Royal Prussia, Ducal Prussia, Courland, Russia, Sweden, France, Switzerland, and finally ended in Alsace (Strasbourg), the land of his ancestors. Dolde described his memories of this journey in a short biography. The aim of this article, therefore, is to provide insight into the educational journey of Johann Jacob Dolde, and to show his determination during the numerous journeys. Indeed, he eventually fulfilled his dream and started a family in Strasbourg. His journey was part of the peregrination medica model and, as his memoirs are not known in Polish literature, is valuable historical material.
Prosopographica V
Authors: Gonis Nikolaos
Published: July 2024

A sequel to a series of notes on high-ranking persons in Late Antique Egypt, continued from APF 67 (2021) 90-101. It includes editions of two papyri described in P.Lond. III and V.
Analytic solution of a fractional-order hepatitis model using Laplace Adomian decomposition method and optimal control analysis
Authors: Aguegboh Nnaemeka S. , Roy Kiogora Phineas , Felix Mutua , Okongo Walter , Diallo Boubacar
Published: July 2024

Infectious illnesses like hepatitis place a heavy cost on global health, and precise mathematical models must be created in order to understand and manage them. The Adomian decomposition method (ADM) and an optimal control strategy are utilized to solve a fractional-order hepatitis model in this research. By adding fractional derivatives to account for memory effects and non-integer order dynamics, the fractional-order model expands the conventional compartmental model to take into account the complexity of hepatitis dynamics. The fractional-order hepatitis model is resolved using the ADM, a powerful and effective analytical approach. This approach offers a series solution that converges quickly, enabling the model’s precise analytical solution to be derived. To identify crucial criteria and enhance control mechanisms for the management of hepatitis, an optimal solution strategy is also introduced. The optimization procedure tries to lessen the disease’s spread and its negative effects on public health. We can find the best interventions, immunization schedules, and treatment regimens to effectively reduce the hepatitis pandemic by integrating the ADM solution with an optimization framework. The findings of this study show that the suggested method may be used to solve the fractional-order hepatitis model and optimize control measures. The analytical solution produced by ADM offers important insights into the underlying dynamics of hepatitis transmission, and the optimization process produces suggestions that public health professionals and politicians may put into practice. In the end, this research presents a promising direction for improving disease control efforts in a fractional-order context and contributes to a deeper understanding of hepatitis epidemiology. The importance of this method is that it gives solutions that coincide with that obtained using the numerical approach.
Association of angiotensin converting enzyme gene insertion/deletion polymorphism with diabetic retinopathy in middle-aged Indians with type 2 diabetes mellitus
Authors: Dutta Pramita , Ghosh Sambuddha , Dasgupta Anindya , Majumder Swati
Published: July 2024

Objectives

There are conflicting reports regarding the association of angiotensin 1 converting enzyme (ACE) gene polymorphism with diabetic retinopathy (DR). We compared ACE gene insertion/deletion (I/D) polymorphism between patients with and without DR in a middle-aged Indian population. The secondary outcome measure was the comparison of ACE gene I/D polymorphism in different grades of DR severity.

Methods

Institutional cross-sectional case-control study with middle-aged (45–64 years) type 2 diabetes patients from Eastern India with DR (DR group) and without DR (NODR group). Polymerase chain reaction (PCR) was used to determine the ACE gene I/D polymorphism through primers flanking the polymorphic region of 287 bp Alu repeat sequence in intron 16.

Results

Genotyping for the ACE gene I/D polymorphisms were done for 107 patients in each group. The presence of DR had no significant association with the prevalence of ACE I/D genotype compared to those without DR either in the recessive model (p=0.588) or in the dominant model (p=0.891). The allele contrast was also similar between DR and NODR (p=0.837) groups. The severity of retinopathy was associated with the ACE I/D genotype in the recessive model (p=0.043) but not in the dominant model (p=0.136). However, the severity of retinopathy was associated with allele contrast (p=0.016).

Conclusions

The ACE gene polymorphism was not associated with diabetic retinopathy in middle-aged Indian patients with type 2 diabetes in our study. However, the severity of DR was associated with the ACE gene polymorphism in these patients.
Materials of garden dormouse summer nests in Germany
Authors: Lang Johannes , Kneisel Raissalyn M.E. , Büchner Sven
Published: July 2024

Nesting is a central topic in the behavioural ecology of many species, but data on the materials used to construct mammal nests are rarely reported. This paper describes the most commonly used components from 25 summer nests of the garden dormouse, a small threatened rodent endemic to Europe. Median nest dry weight of 25 nests was 15.5 g (10.3–21.1 g) and moss was the most common material (78 %), followed by leaves (9 %). Mosses were also the most frequently used material, with Hypnum cupressiforme being the most frequently used taxon in 11 out of 25 nests.
Linear and nonlinear optical studies on successfully mixed vanadium oxide and zinc oxide nanoparticles synthesized by sol–gel technique
Authors: Moustafa Samar , Ali Atif Mossad , Shawaf Jawaher , Al dirham Sharah H. , Alqhtani Norah , Al-Ghamdi Salah A. , Helali Saloua , Fares Hesham , Rashad Mohamed
Published: July 2024

In this study, V2O5, 5ZnO/10V2O5, and ZnO, 10ZnO/10V2O5 nanocomposites were synthesized by the sol–gel method. The sol–gel technique is an important process for the fabrication of advanced oxide materials with desirable catalytic, optical, and structural properties. The varieties and flexibilities of sol–gel techniques help in preparing materials with extremely specific properties. For the presented samples, three types of phases were assessed. The average crystalline size of V2O5, 5ZnO/10V2O5 and ZnO, 10ZnO/10V2O5 nanocomposites were found to be 25, 26, 14.5, and 15.5 nm, respectively. SEM images showed three different shapes of semi-tube, semi-spherical, and semi-flower. The pure samples of V2O5 and ZnO showed semi-tube shapes. 5ZnO/10V2O5 shows a spherical shape with average dimeter of 0.6 µm. Strong dependence of the direct optical band gap was observed on different compositions that varied within the range of (2.33–2.73 eV). Conversely, the indirect values varied within the range of 2.119–2.35 eV. On the other hand, 10ZnO/10V2O5 has semi flower shape with different layers. Optical parameters, such as optical band gap, extension coefficient, tails of localized states, and refractive index, were gauged for these nanocomposites. In addition, the mean refractive index of ZnO is lower than that of V2O5, with differences observed between 5ZnO/10V2O5 and 10ZnO/10V2O5 nanocomposites.
Experimental study on municipal solid waste incineration ash micro-powder as concrete admixture
Authors: Hanghang Li , Dongsheng Shi , Hao Li , Dongdong Ren
Published: July 2024

To improve the utilization rate of municipal solid waste incineration (MSWI) ash and achieve resource recycling, this article conducted research on grinding MSWI ash into fine powder for use as a concrete admixture. Initially, the physical and chemical properties of the MSWI ash micro-powder were tested. Subsequently, different amounts of MSWI ash powder concrete were prepared. The macro and micro properties of the concrete were then tested. Finally, a life cycle assessment was utilized to evaluate and compare ordinary concrete with MSWI ash micro-powder concrete. The results indicate that the chemical composition of the MSWI ash micro-powder is similar to that of cement clinker. It exhibits potential hydraulicity and a slow hydration reaction, making it an active admixture suitable for concrete raw materials. With the increasing proportion of MSWI ash micro-powder, the rate of hydration reaction in concrete slows down, resulting in decreased mechanical properties. The microhardness value of the hardened cement paste in MSWI ash micro-powder concrete is lower than that of ordinary concrete. Moreover, the addition of MSWI ash micro-powder helps mitigate the environmental impact of concrete in terms of non-biological energy loss and CO2 emissions.
Independent mobility and physical activity among children residing in an ultra-dense metropolis
Authors: Huang Wendy Y. , Feng Jie , Wong Stephen H.
Published: July 2024

Objectives

Independent mobility (IM), which is defined as the freedom of children moving without adult supervision, has been found to be positively associated with physical activity (PA). This study explored IM by sociodemographic factors and type of neighborhoods and its association with PA among children in Hong Kong.

Methods

A convenience sample of 330 children aged 8–12 years and their parents was recruited. The children wore an ActiGraph accelerometer for eight consecutive days to measure PA and sedentary time (ST). Parents reported parents’ license and children self-reported their actual mobility. Generalized estimating equations were conducted to examine the associations of IM with sociodemographics (e.g., children’s age, sex, body weight status, parents’ age, sex, maternal education) and type of neighborhood. Linear mixed models were performed to determine the associations of IM with PA and ST.

Results

Valid data from 296 children (8.8±0.6 years old, 42.2 % boys) were included in analysis. Children residing in sprawl and rural areas had greater parents’ license and actual mobility than those in urban areas. Greater parents’ license was associated with more moderate-to-vigorous intensity PA (MVPA) on weekend days (β=1.33, 95% CI: 0.15–2.51), while children’s actual mobility was positively associated with MVPA on weekdays (β=1.14, 95% CI: 0.10–2.18).

Conclusions

In densely populated metropolis, children living in highly urbanized areas with higher SES experienced reduced parental license and actual mobility compared to their peers in less affluent neighborhoods, irrespective of the level of urbanization.
Kinetics and Kinematics of the Push Press, Push Jerk, and Split Jerk
Authors: Soriano Marcos A. , Jiménez-Ormeño Ester , Lake Jason P. , McMahon John J. , Gallo-Salazar César , Mundy Peter , Comfort Paul
Published: July 2024

Soriano, MA, Jiménez-Ormeño, E, Lake, JP, McMahon, JJ, Gallo-Salazar, C, Mundy, P, and Comfort, P. Kinetics and kinematics of the push press, push jerk, and split jerk. J Strength Cond Res 38(8): 1359–1365, 2024—The aim of this study was to explore the kinetics and kinematics across incremental loads with the push press (PP), push jerk (PJ), and split jerk (SJ). Eighteen resistance-trained men performed the 1 repetition maximum (1RM) tests (visit 1) 3–7 days before an incremental loading protocol (60, 75, and 90% 1RM) of the 3 exercises (visit 2). Kinetics and kinematics were derived from force-time data and compared using a repeated-measures analysis of variance with load and exercise as within-subject factors. Dependent variables for the biomechanics assessment were categorized as output (power and impulse), driver (force and work), and strategy (displacement and duration) metrics. The interrepetition reliability was assessed using the intraclass correlation coefficient and coefficient of variation. The PP, PJ, and SJ 1RM performance were 89.7 ± 15.4, 95.6 ± 14.4, and 103.0 ± 16.9 kg, respectively. Driver, strategy, and outcome metrics displayed moderate-to-excellent (intraclass correlation coefficient: 0.58–0.98) reliability with acceptable variability (% coefficient of variation: 2.02–10.00). Increased load resulted in significantly large increases in force, work, displacement, duration, power, and impulse (p < 0.001,

= 0.534–0.903). Exercise selection had a significant and large effect on power, impulse, work, and force (p < 0.016,

= 0.387–0.534). There was a significant and large effect of load × exercise interaction on work, displacement, and duration (p < 0.019,

= 0.158–0.220). Practitioners are encouraged to use heavier loads (90 > 75 > 60% 1RM) during the SJ exercise to maximize output, driver, and strategy kinetics and kinematics.
High-Speed Efforts of Elite Association Football Referees in National and International Matches
Authors: Amatori Stefano , Helsen Werner F. , Baldari Carlo , Serra Tommaso , Belli Annalisa , Guidetti Laura , Rocchi Marco B. L. , Sisti Davide , Perroni Fabrizio
Published: July 2024

Amatori, S, Helsen, WF, Baldari, C, Serra, T, Belli, A, Guidetti, L, Rocchi, MBL, Sisti, D, and Perroni, F. High-speed efforts of elite association football referees in national and international matches. J Strength Cond Res 38(8): e417–e422, 2024—Field referees (FRs) need to move throughout the pitch to identify any infringements of the game's laws. Their performance depends on technical, tactical, physical, physiological, and mental factors. This retrospective study aimed to examine and assess the physical and physiological parameters as a function of time in elite association football referees during official matches. Global positioning system (match time, distance in different intensity ranges [low-intensity, high-speed, very high-speed running, and sprinting], average and peak speed, distance in accelerations or decelerations) and heart rate (average and peak) data from 212 national and international football matches were analyzed. A linear mixed-model analysis was performed to assess the differences between halves and between the three 15-minute sections of each half-time for all the physical and physiological variables collected. A significant effect of match half was found for the game time (p < 0.001) and the standing time (p = 0.005), both higher in the second half, and for the average speed (p = 0.017), which was lower in the second half. Total distance (p < 0.001), low-intensity distance (p = 0.004), and average speed (p = 0.007) all showed a reduction as a function of time. More than 7.800 high-speed intervals were detected. Accelerative actions within 3 seconds characterized most of the high-speed efforts of an FR during a match. Significant differences emerged in the way the match intensity is distributed across the match, analyzed both in halves (first vs. second) and 15-minute intervals within each half. It is important to emphasize the importance of high-speed training with a focus on a faster transition from low- to high-speed running to keep up with the play to get into an appropriate position and subsequently make the correct decisions.
What About Water? Implications for Body Composition Assessment in Military Personnel
Authors: Sergi Tina E. , Roberts Brandon M. , Heileson Jeffery L.
Published: July 2024

Sergi, TE, Roberts, BM, and Heileson, JL. What About Water? Implications for Body Composition Assessment in Military Personnel. J Strength Cond Res 38(9): e534–e540, 2024—Body composition standards ensure service members maintain physical fitness, wellness, and support mission readiness. Anthropometric techniques (i.e., height/mass, circumference-based “tape test”) have been the primary screening and percent body fat (%BF) assessment method in military personnel for about 4 decades. Recently, the Army and Marine Corps have implemented more advanced body composition assessment methods, such as air displacement plethysmography (ADP), multifrequency bioelectrical impedance analysis (MF-BIA), and dual-energy x-ray absorptiometry (DXA), to serve as supplemental %BF assessment after failing the tape test. Although supplemental assessments are intended to improve on the accuracy and precision of the tape test, preassessment standardization, specifically regarding acute water ingestion (AWI), is lacking. Thus, the purpose of this narrative review was to (a) summarize the available literature regarding the influence of AWI on body composition estimates derived from ADP, MF-BIA, and DXA and (b) provide evidence-based recommendations for researchers and practitioners. Studies indicate that AWI increases %BF estimates with ADP (4 of 6 [4/6] observations) and MF-BIA (6/7), whereas AWI increases muscle mass (6/6) and likely decreases %BF (2/3) when obtained by DXA. In conclusion, ADP, MF-BIA, and DXA are susceptible to confounding from AWI, leading to inaccurate body composition estimates that may negatively affect the careers of military personnel. Based on the findings from this narrative review, military practitioners and researchers should (a) follow manufacturer guidelines for calorie intake [food and fluid] and exercise avoidance, (b) conduct urine-specific gravity testing [if possible], and (c) limit AWI to <250 ml before assessment.
Seasonal Muscular Power Changes: Considerations of Concurrent Resistance and Field-Based Training in Professional Rugby League
Authors: Redman Kellyanne J. , Wade Logan , Whitley Ryan , Connick Mark J. , Kelly Vincent G. , Beckman Emma M.
Published: July 2024

Redman, KJ, Wade, L, Whitley, R, Connick, MJ, Kelly, VG, and Beckman, EM. Seasonal muscular power changes: considerations of concurrent resistance and field-based training in professional rugby league. J Strength Cond Res 38(9): 1620–1626, 2024—A rugby league player's ability to develop or maintain lower-body power will be significantly influenced by the resistance and field-based training loads completed. This study aimed to examine the power changes across a rugby league season and to investigate the relationship of concurrent training and training experience on power changes. Eighteen rugby league players participated in this study. Lower-body power was evaluated using a countermovement jump throughout the season. Four measures of external training loads were collected. A Friedman's test was used to assess differences in power throughout different phases of the season. A series of Spearman's rank-order correlations were conducted to assess the relationship between percentage changes in power during the training block, external training loads, and training experience. Countermovement jump peak velocity significantly decreased from the start (p = 0.006) and end of pre-season (p = 0.022) to the late competition. Correlation analysis revealed a large significant association between early competition field-based external loads (relative (r
s = −0.571) and total distance (r
s = −0.628)) and change in peak power. Very large significant negative relationships were also observed between mid-competition volume load with change in peak force (r
s = −0.825) and peak power (r
s = −0.736). Training experience was not significantly associated with changes in muscular power variables throughout this study. Coaches should seek to monitor changes in peak power when competition begins and to assist with decision-making for potential adjustments to running volume and intensity during field-based sessions.
The Relationship Between Motor Competence and Landing Error Scoring System Performance in Youth Soccer Players
Authors: Duncan Michael J. , Heering Theresa , Tallis Jason , Guimaraes-Ferreira Lucas , Martins Ricardo , Crotti Matteo , Barnett Lisa , Lander Natalie , Lyons Mark
Published: July 2024

Duncan, MJ, Heering, T, Tallis, J, Guimaraes-Ferreira, L, Martins, R, Crotti, M, Barnett, L, Lander, N, and Lyons, M. The relationship between motor competence and landing error scoring system performance in youth soccer players. J Strength Cond Res 38(9): e496–e502, 2024—This study examined the relationship between motor competence (MC) and Landing Error Scoring System (LESS) performance in a sample of male junior grassroots footballers aged 10–13 years. Ninety-eight boys aged 10–13 years (mean ± SD = 11.7 ± 1 years) undertook assessment of MC, using the Test of Gross Motor Development (third edition) and anterior cruciate ligament (ACL) injury risk using the LESS. Height and mass were assessed from which maturity status was predicted. Multiple backward linear regressions indicated a significant model (p = 0.001), which explained 49% of the variance in LESS scores. Locomotor MC (β = −0.538, p = 0.001), object control MC (β = −0.261, p = 0.004), and age (β = 1.17, p = 0.03) significantly contributed to the model. Maturity offset (p = 0.100) was not significant. Analysis of covariance (controlling for age and maturity offset) indicated a significant difference in locomotor MC between those classified as poor for LESS. A similar result was observed for object control MC (p = 0.003,

= 0.09), where those classed as poor for LESS had significantly poorer object control MC compared with those classed as excellent, good, and moderate. The results of this study indicate that there is a relationship between both locomotor and object control MC and errors in drop jump landing mechanics in boys aged 10–13 years, with MC explaining nearly 50% of the variance in LESS scores. Practically, this study indicates that MC, particularly locomotor MC, has potential to identify performance in jump landing tests that are associated with increased risk of ACL injury in boys who play grassroots soccer.
Brain Endurance Training Improves and Maintains Chest Press and Squat Jump Performance When Fatigued
Authors: Díaz-García Jesús , López-Gajardo Miguel Ángel , Parraca José Alberto , Batalha Nunho , López-Rodríguez Rubén , Ring Christopher
Published: July 2024

Díaz-García, J, López-Gajardo, MÁ, Parraca, JA, Batalla, N, López-Rodríguez, R, and Ring, C. Brain endurance training improves and maintains chest press and squat jump performance when fatigued. J Strength Cond Res 38(9): 1568–1575, 2024—Mental fatigue can impair resistance exercise performance. Brain endurance training (BET)—the addition of demanding cognitive tasks to standard exercise training—improves endurance exercise performance more than standard training. Although BET has yet to be evaluated with resistance exercise, it is expected to improve performance, particularly when the performer feels mentally fatigued. The study employed a pretest (week 0), midtest (week 3), posttest (week 6), and follow-up (week 9) design, with subjects randomized to BET (n = 46) or control (exercise training) (n = 45) groups. In testing sessions, subjects performed chest press and squat jump exercises to failure before (feeling fresh) and after (feeling tired) a 30-minute cognitively demanding Stroop task. Training comprised 5 BET or control training sessions per week for 6 weeks. In each training session, subjects completed 4 sets of each exercise to failure, with each exercise set preceded by a 3-minute cognitive task (BET) or rest (control). Exercise performance (number of repetitions to failure) and mental fatigue markers were assessed. In pretesting, exercise performance did not differ between the groups. In midtesting and posttesting, BET performed more chest press and squat jump repetitions when fatigued by the 30-minute Stroop than control. The mental fatigue elicited by the Stroop task gradually declined with training in BET compared with control. In conclusion, BET enhanced resistance exercise performance compared with standard training when tested subsequent to a mentally fatiguing cognitive task. These benefits were maintained weeks after training ended. Brain endurance training is an effective method to mitigate the deleterious effects of mental fatigue on resistance exercise performance.
Predicting 1 Repetition Maximum Squat With Peak Force Obtained From Isometric Squat at Multiple Positions
Authors: Tan Wei Zhi Nicholas , Lum Danny
Published: July 2024

Tan, WZN and Lum, D. Predicting 1 repetition maximum squat with peak force obtained from isometric squat at multiple positions. J Strength Cond Res 38(9): 1543–1550, 2024—This study investigated whether the use of peak force (PF) obtained from multiple joint positions during isometric squat (IsoSqt) can predict of 1-repetition maximum (1RM) squat with high precision. Twenty-nine male and female resistance-trained athletes (age = 23.0 ± 3.7 years, height = 1.57 ± 0.06 m, body mass = 56.6 ± 9.1 kg, 1RM squat = 104.6 ± 24.2) performed the 1RM squat, and IsoSqt at 60°, 90°, and 120° knee angles on 3 separate occasions. Peak force obtained from IsoSqt at all positions significantly correlated with 1RM squat (r = 0.684–0.940, p < 0.05). Linear regression analysis based on group data showed r
2 = 0.903, based on male data only, r
2 = 0.826, and based on female data only, r
2 = 0.855. Predicted 1RM squat using linear regression equations based on group, male-only, and female-only data showed nonsignificant differences of 0.02–0.6% from actual 1RM squat (p = 0.812–0.947, 95% CI = −8.00 to 10.08), with error of estimate of 1.5–2.3%. In addition, Bland-Altman analysis showed a mean bias of −1.04 to 0.35 kg, 95% CI = −10.08 to 8.00 kg. The results showed that using PF obtained from IsoSqt at multiple positions was able to predict 1RM squat with low difference from actual 1RM squat. Furthermore, using linear regression equation derived from gender-specific data was able to predict 1RM squat with higher precision than that based on group data.
Kinetic Predictors of Weightlifting Performance in Young Weightlifters
Authors: Morris Stephanie J. , Oliver Jon L. , Pedley Jason S. , Radnor John M. , Haff G. Gregory , Cooper Stephen-Mark , Lloyd Rhodri S.
Published: July 2024

Morris, SJ, Oliver, JL, Pedley, JS, Radnor, JM, Haff, GG, Cooper, S-M, and Lloyd, RS. Kinetic predictors of weightlifting performance in young weightlifters. J Strength Cond Res 38(9): 1551–1560, 2024—Relationships between force-generating capabilities and weightlifting performance (e.g., snatch, clean and jerk [C&J], and combined total) have previously been explored in adult weightlifters; however, associations in young athletes are unknown. The purpose of this study was twofold: (a) to examine the relationships between countermovement jump (CMJ) and isometric midthigh pull (IMTP) kinetics and weightlifting performance in young weightlifters and (b) to determine the proportion of weightlifting performance that could be accounted for by CMJ and IMTP kinetics using principal component analysis (PCA). Thirty-seven young weightlifters (12–18 years of age) completed 3 trials of CMJ and 2 trials of the IMTP assessments on dual force plates. Recent competition maximum loads, obtained within 2 weeks of the data collection, for the C&J and snatch were also recorded. Pearson's zero-order correlation coefficients demonstrated moderate to very high correlations (r = 0.359–0.801; all p ≤ Benjamini–Hochberg critical values [B-Hα]) between CMJ kinetic variables, including jump height, average braking force, average braking velocity, absolute and relative braking net impulse, absolute and relative force at minimum displacement, absolute and relative propulsive force, absolute and relative propulsive net impulse and average propulsive velocity, and weightlifting performance. High to very high correlations were evident between IMTP peak force and relative peak force and all weightlifting performance metrics (snatch, C&J, combined total, combined total [kg]/body mass [kg−0.67], and Sinclair’s total; r = 0.538–0.796; p ≤ B-Hα). Components from the PCA were used to conduct stepwise, multiple, linear regression analyses. Moderate (45.8–52.9%) and large percentages (79.1–81.3%) of variance in absolute measures of weightlifting performance were explained by IMTP peak force variables and CMJ propulsive variables, respectively. These novel findings indicate that IMTP peak force variables and CMJ propulsive variables could provide valuable insight for talent identification and long-term athletic development in junior weightlifting pathways.
The Effects of Volume-Matched 1- and 2-Day Repeated Backward Sprint Training Formats on Physical Performance in Youth Male Soccer Players
Authors: Bouguezzi Raja , Negra Yassine , Sammoud Senda , Uthoff Aaron , Moran Jason , Behrens Martin , Chaabene Helmi
Published: July 2024

Bouguezzi, R, Negra, Y, Sammoud, S, Uthoff, A, Moran, J, Behrens, M, and Chaabene, H. The effects of volume-matched 1- and 2-day repeated backward sprint training formats on physical performance in youth male soccer players. J Strength Cond Res 38(10): e587–e594, 2024—This study examined the effects of a 6-week, 1 vs. 2 sessions of volume-matched weekly repeated backward sprint training (RBST) on measures of physical fitness in youth male soccer players. Thirty male youth soccer players from a regional soccer team were randomly assigned to a 2-day group (n = 15; age = 16.40 ± 0.64 years; Maturity-offset = 2.19 ± 0.65 years) or a 1-day group (n = 15; age = 16.27 ± 0.51 years; Maturity-offset = 1.91 ± 0.40 years). Measures of jumping ability, linear sprint speed, change-of-direction (CoD) speed, aerobic endurance (AE), and repeated sprint ability (RSA) were measured before and after 6 weeks of training. The training interventions involved 1 to 2 sets, each comprising 7 repetitions over a 20-m distance of RBST in the 2-day group, and 2 to 4 sets, also with 7 repetitions each over the same distance, in the 1-day group. Statistical analyses were conducted using the analysis of covariance model with baseline measurements entered as covariates. Results indicated that RBST over 2 days generated greater benefits compared with a single day for improving CoD speed (∆4.91 vs. 0.04%; effect size [d] = 0.78 vs. 0.00, respectively), linear sprint speed (10-m: ∆4.74 vs. 0.36%; d = 0.96 vs. 0.00, respectively; 20 m: ∆3.34 vs. 0.82%; d = 1.00 vs. 0.49, respectively), and RSA performances (RSAbest: ∆2.61 vs. 0.29%; d = 0.71 vs. 0.16, respectively; RSAmean: ∆2.86 vs. 0.89%; d = 0.59 vs. 0.16, respectively; RSAtotal: ∆2.86 vs. 0.89%; d = 0.62 vs. 0.41, respectively). However, similar improvements in the 2 RBST formats were observed on jumping (2-day group: ∆6.9%; d = 0.75; 1-day group: ∆10.6%, d = 1.26) and AE performance (2-day group: ∆17.24%, d = 1.04; 1-day group: ∆27.25%, d = 2.25). In summary, the findings suggest that, when volume is matched, spreading the RBST regimen over 2 days may result in greater improvements compared with a single-day approach for enhancing CoD speed, linear sprint speed, and RSA performance.
Performing Lower-Limb Strength Exercises Before or After Training Does not Influence Fatigue Indices in Competitive Youth Soccer Players
Authors: Gantzer Carson , Huff Drake , Butterick Brooke , Chalmers Samuel , Marshall Paul , Lovell Ric , Siegler Jason C.
Published: July 2024

Gantzer, C, Huff, D, Butterick, B, Chalmers, S, Marshall, P, Lovell, R, and Siegler, JC. Performing lower-limb strength exercises before or after training does not influence fatigue indices in competitive youth soccer players. J Strength Cond Res 38(10): 1760–1767, 2024—A multicenter approach was used to conduct a controlled, laboratory-based study (Part A) in conjunction with an ecologically focused, field-based study (Part B) of the influence of timing on hamstring fatigue induced by lower-limb strength exercises. Part A required players to perform the FIFA 11+ warm-up before a simulated soccer training session, whereas the other session involved removing the lower-limb strength exercises from the warm-up and delivering them after the simulated session. For Part B, players completed 2 live training sessions, where one session included the Nordic hamstring exercise (NHE) as part of a standardized warm-up before training and the other session incorporated the NHE at the end of training. Maximal hamstring force (MVC), rate of force development (RFD), countermovement jump (CMJ), and sprint speed (SS) were assessed before, during, and after the simulation and field training, respectively, to quantify fatigue across both study cohorts. There was no suggestion that timing of the intervention had an influence fatigue in either Part A or B, with no condition (MVC [Part A & B]: p > 0.43; RFD: p = 0.43; CMJ: p = 0.10; SS: p = 0.62), time (MVC: p > 0.30; RFD: p = 0.72; CMJ: p = 0.87; SS: p = 0.85), or interactions (MVC: p > 0.93; RFD: p = 0.78; CMJ: p = 0.99; SS: p = 0.94) evident. Our findings suggest youth soccer coaches should not be concerned with the timing of interventions, allowing them to focus instead on adherence and player buy-in.
The Effect of Creatine Supplementation on Resistance Training–Based Changes to Body Composition: A Systematic Review and Meta-analysis
Authors: Desai Imtiaz , Wewege Michael A. , Jones Matthew D. , Clifford Briana K. , Pandit Anurag , Kaakoush Nadeem O. , Simar David , Hagstrom Amanda D.
Published: July 2024

Desai, I, Wewege, MA, Jones, MD, Clifford, BK, Pandit, A, Kaakoush, NO, Simar, D, and Hagstrom, AD. The effect of creatine supplementation on resistance training-based changes to body composition: A systematic review and meta-analysis. J Strength Cond Res 38(10): 1813–1821, 2024—The purpose of this review was to determine the added effect of creatine supplementation on changes in body composition with resistance training in adults younger than 50 years. The review protocol was preregistered on the Open Science Framework (osf.io/x48a6/). Our primary outcome was lean body mass (LBM); secondary outcomes were body fat percentage (%) and body fat mass (kg). We performed a random-effects meta-analysis in R using the metafor package. Subgroup analyses were conducted to examine the effects of training status and use of a carbohydrate drink with creatine. We conducted a meta-regression to examine the moderating effect of total training volume. Statistical significance was set at p < 0.05. One thousand six hundred ninety-four records were screened, and 67 full-text articles were assessed for eligibility. Twelve studies were included in the meta-analysis. Fifty-two percentages of the studies had low risk, 41% some concerns, and 7% high risk of bias. Compared with resistance training (RT) alone, creatine supplementation increased LBM by 1.14 kg (95% CI 0.69 to 1.59), and reduced body fat percentage by −0.88% (95% CI −1.66 to −0.11) and body fat mass by −0.73 kg (95% CI −1.34 to −0.11). There were no differences between training status or carbohydrate subgroups. Training volume was not associated with effect size in all outcomes; 7 g or 0.3 g/kg of body mass of creatine per day is likely to increase LBM by 1 kg and reduce fat mass by 0.7 kg more than RT alone. Concurrent carbohydrate ingestion did not enhance the hypertrophy benefits of creatine.
Microvascular Reactivity Is Greater Following Blood Flow Restriction Resistance Exercise Compared with Traditional Resistance Exercise
Authors: Perlet Michael R. , Hosick Peter A. , Licameli Nicholas , Matthews Evan L.
Published: July 2024

Perlet, MR, Hosick, PA, Licameli, N, and Matthews, EL. Microvascular reactivity is greater following blood flow restriction resistance exercise compared with traditional resistance exercise. J Strength Cond Res 38(10): e553–e562, 2024—Chronic blood flow restriction (BFR) resistance exercise can improve muscular strength, hypertrophy, and microvasculature function, but the acute microvascular effects are unknown. We aimed to test the effects of acute BFR resistance exercise on postexercise microvascular reactivity in an exercising muscle and nonexercising muscle compared with traditional resistance exercise (TRE). Twenty-five adults (men = 14, women = 11, age: 22 ± 3 years, body mass: 71.69 ± 14.49 kg, height: 170 ± 10 cm) completed barbell back squat 1-repetition maximum (1RM) testing followed by 2 randomized and counterbalanced resistance exercise visits separated by ≥48 hours. The 2 visits involved either BFR (4 sets of 30-15-15-15 repetitions at 30% 1RM, with 60-second rest intervals) or TRE (4 sets of 10 repetitions at 70% 1RM, 60-second rest intervals). During each exercise visit, a pre- and postbarbell back squat vascular occlusion test was performed using near-infrared spectroscopy to measure skeletal muscle oxygen (SmO2) in the vastus lateralis (VL) and flexor carpi radialis (FCR). Two-way repeated-measures ANOVA found an interaction effect (p = 0.020) for SmO2 reactivity in the VL. Post hoc analysis found greater reactive hyperemia postexercise in the VL for the BFR condition (p < 0.001) but not the TRE condition (p ≥ 0.05). There were no time, condition, or interaction effects (all p > 0.05) for the same analysis in the FCR. This analysis suggests that BFR, but not TRE, lead to acutely improved microvasculature function. Moreover, it suggests that the effects of BFR resistance exercise are local to the exercised or occluded limb and not systemic.
Velocity-Based Training Affects Function, Strength, and Power in Persons with Parkinson's Disease
Authors: Calaway Caleb C. , Martinez Kylie J. , Calzada Bichili Ana Raquel , Caplan Joseph H. , Milgrim William P. , Mann J. Bryan , Haq Ihtsham , Signorile Joseph F.
Published: July 2024

Calaway, CC, Martinez, KJ, Calzada Bichili, AR, Caplan, JH, Milgrim, WP, Mann, JB, Haq, I, and Signorile, JF. Velocity-based training affects function, strength, and power in persons with Parkinson’s disease. J Strength Cond Res 38(10): 1800–1807, 2024—Velocity-based training (VBT) is commonly associated with high-level athletes. No study has examined the effects of VBT on performance in persons with Parkinson's disease (PD). The objective of the study was to compare the effects of 10 and 30% velocity-loss threshold protocols on changes in functional performance, strength, and power in persons with PD after 12 weeks of supervised VBT, 3 days per week. Twenty-one subjects with PD (72.9 ± 5.9 y) were randomly assigned to the 10% or 30% velocity-loss threshold group and performed the 6-m walk test at habitual and maximal gait speed (6MWTMax), the 5 time sit-to-stand test (5 × STS), 1 repetition maximum (1RM), and peak power (PP) testing for the chest press (CP) and leg press (LP) exercise. A mixed ANOVA with significance was set a priori at 0.05 revealed that significant time effects were seen for the 6MWT at maximal speed (MDiff ± SD = 0.22 ± 0.04 m·s−1, p < 0.001), 5-time sit-to-stand time (−1.48 ± 0.45 seconds, p = 0.005) and power (75.5 ± 22.7 W, p = 0.005), 1RM for CP (5.1 ± 1.1 kg, p < 0.001) and LP (12.6 ± 3.7 kg, p = 0.005), and LP-PP (43.6 ± 13.2 W, p = 0.006). Secondary analyses revealed time effects for the load at which PP was achieved for the CP exercise. A Wilcoxon signed-rank test revealed no significant differences in the percentage of 1RM at which PP was achieved for either condition. Results indicate that VBT is an effective training modality for improving functional capacity, strength, and power in persons with PD; however, shifts in force-velocity relationships were not evidenced.
Tournament Recovery Profiles and Physical Demands in a Collegiate Women’s Tennis Team
Authors: Tendero-Ortiz Elena , Johnson Matthew J. , Horsfall Cameron M. , Vondrasek Joseph D. , Grosicki Gregory J. , Riemann Bryan L. , Flatt Andrew A.
Published: July 2024

Tendero-Ortiz, E, Johnson, MJ, Horsfall, CM, Vondrasek, JD, Grosicki, GJ, Riemann, BL, and Flatt, AA. Tournament recovery profiles and physical demands in a collegiate women's tennis team. J Strength Cond Res 38(10): 1786–1792, 2024—We aimed to characterize recovery profiles and tournament physical demands in women's collegiate tennis players. A Division 1 team (n = 9) participated in the study. Markers of cardiac autonomic (resting heart rate [HR], HR variability), neuromuscular (isometric handgrip strength, seated single-arm shot-put test [SSAPT], hexagon agility, countermovement jump characteristics), and perceptual recovery were obtained before the tournament (baseline) and again 1 and 2 days posttournament. Cardiorespiratory (HR) and movement characteristics from matches were quantified with wearable devices. p values < 0.05 were statistically significant. No recovery markers differed from baseline (p > 0.05), although small effect size reductions 1 day posttournament were noted for SSAPT, hexagon agility, and select countermovement jump characteristics. In addition, hexagon agility times and SSAPT were slower (p < 0.01) and shorter (p < 0.05), respectively, at 1 versus 2 days posttournament. Similarly, relative to 1 day posttournament, perceptual makers were improved 2 days posttournament (ps < 0.05). Mean and peak HR were higher for singles versus doubles matches  (p < 0.05). Except for average speed, movement parameters were greater during singles versus doubles matches (p < 0.05). Markers of recovery were minimally affected 1 day posttournament relative to baseline, but perceptual and select neuromuscular markers were most improved 2 days posttournament. Thus, passive rest or limited intensity training 1 day posttournament seems advisable. Competition HR and movement profiles inform practitioners of the cardiorespiratory and locomotor demands of women's collegiate tennis, which may be useful in designing preparatory conditioning programs to ensure that players attain match-specific physical capacities in training before competition.
Are Load-Velocity Estimates of Bench Press Maximal Strength as Accurate as Actual 1-Repetition Maximum Testing?
Authors: Cabarkapa Damjana V. , Fry Andrew C. , Kavadas N. Gabriel , Cabarkapa Dimitrije
Published: July 2024

Cabarkapa, DV, Fry, AC, Kavadas, NG, and Cabarkapa, D. Are load-velocity estimates of bench press maximal strength as accurate as actual 1-repetition maximum testing? J Strength Cond Res 38(10): e563–e573, 2024—The purpose of the present investigation was to determine if using maximal velocity measures while lifting submaximal loads as a predictor of bench press maximal strength (i.e., 1 repetition maximum [1RM]) is more accurate than the actual 1RM test and determine which specific submaximal loads best estimate 1RM bench press strength with the lowest variability when compared with actual 1RM tests. Sixteen recreationally trained subjects performed 5 testing sessions. The first and second sessions included the actual 1RM bench press testing, whereas the remaining 3 sessions consisted of performing one repetition of a bench press exercise in a series of incremental loads, starting at 20% 1RM and increasing the resistance by 10% until reaching the 90% of individual's 1RM. For each participant, linear regressions using bar velocities at each relative load were used to estimate 1RM capabilities, using the predetermined 1RM barbell velocities from actual 1RM testing. The results of the present investigation indicated the following: (a) actual bench press 1RM can be a highly reliable assessment of maximal strength; (b) having a greater number of loads included in the equations increases the accuracy of 1RM estimation; (c) practitioners should incorporate light (e.g., 20% 1RM) and heavy (e.g., 80 and/or 90% 1RM) loads when estimating 1RM from load-velocity profiles; and (d) most load-velocity regression equations for estimating strength are not as accurate as actual 1RM tests for the free-weight bench press. Those who use load-velocity testing to estimate 1RM strength must be willing to accept the accompanying error for most loading protocols.
Kinematic and Kinetic Differences Between Ball Rotational Exercises and the Throwing Motion in Collegiate Baseball Athletes
Authors: Mylott Joseph A. , Potts Emily M. , Wolf Jakob H. , Bullock Garrett S. , Nicholson Kristen F.
Published: July 2024

Mylott, JA, Potts, EM, Wolf, JH, Bullock, GS, and Nicholson, KF. Kinematic and kinetic differences between ball rotational exercises and the throwing motion in collegiate baseball athletes. J Strength Cond Res 38(10): 1753–1759, 2024—The purpose of this study was to observe the associations that medicine ball pushes and chops have on the lower extremities regarding ground reaction forces (GRF) and lead knee flexion angles and to compare these values with a regular baseball overhead throw. Lower extremity kinetics and kinematics were obtained via force plates and marker motion capture. Subjects (n = 35) included baseball players (age 19.7 ± 1.5 years). Five medicine ball movements of each type along with at least 3 pitches or 5 throws off the mound were recorded for data collection. Statistical parametric mapping, including analysis of variance and 2-way t-tests, was used to compare the variables of interest between the movements for continuous time data. All kinematic and kinetic variables were significantly different (p < 0.05) for some time during the motion between the different trial types of medicine ball exercises and throws. A medicine ball chop can increase peak drive leg GRF, whereas a push can help an athlete keep greater driver leg GRF and maintain ground connection into foot plant. A push helps train lead leg deficiencies in the delivery. Both the medicine ball chop and push have benefits for training lead leg stabilization and extension.
TABUS E TEMAS POLÊMICOS – A LITERATURA INFANTIL E JUVENIL SOB CENSURA
Authors: Rodrigues Sílvia de Fátima Pilegi , Souza Renata Junqueira de
Published: July 2024

O objetivo deste texto é suscitar reflexões em torno da censura de obras literárias voltadas ao público infantil e juvenil que tocam em tabus e temas polêmicos de nossa sociedade. Parte-se da premissa de que a leitura de textos que tematizam conflitos e dramas humanos pode possibilitar aos leitores pensarem sobre suas próprias vidas e experiências e ressignificá-las. Para instaurar o diálogo aqui proposto, indaga-se: é possível ao professor/mediador de leitura não abordar tabus e temas polêmicos no interior das escolas e, mesmo assim, colocar-se como formador de leitores sensíveis, críticos e proficientes? Há literatura infantil inadequada ou inadequação na forma de abordagem dos textos?A análise se apoia nos contos A triste história de Eredegalda (BRANT, 2013) e Pele de Asno (PERRAULT, 1697/2016) e na Nota Técnica sobre o livro “Enquanto o sono não vem” (CEALE, 2017).
ANDERSEN, GRIMM Y PERRAULT TAMBIÉN SON DIGITALES: CUENTOS CLÁSICOS INFANTILES EN LAS APLICACIONES DE LECTURA DE ANDROID E IOS.
Authors: Prieto-Paíno Cristina , García-Rodríguez Araceli , Gómez-Díaz Raquel
Published: July 2024

Este trabajo tiene como objetivo principal establecer una caracterización de las aplicaciones de lectura infantil para dispositivos móviles que contienen cuentos clásicos universales. Para ello se seleccionaron y analizaron 67 apps de lectura que incluyen cuentos clásicos infantiles, se realizó una caracterización de dichas aplicaciones estudiando el número de títulos que incluyen, las formas en que éstos se presentan (versiones o adaptaciones), y cuáles son los autores, títulos y personajes más frecuentes en las mismas. Se llegó a la conclusión de que los cuentos clásicos populares y las fábulas son habituales en estas aplicaciones de lectura, ya sea adaptados o versionados, y que los títulos y personajes más frecuentes de la literatura infantil se mantienen para la literatura infantil digital.