The purpose of this study was to determine the importance of physical qualities for speed and change of direction (CoD) ability in female soccer players. Data were collected on 10 female soccer players who were part of a professional English Women's Super League team. Player assessments included anthropometric (stature and body mass), body composition (dual-energy X-ray absorptiometry), speed (10m, 30m sprint), CoD ability (505 agility), aerobic (Yo-Yo Intermittent Recovery Test), lower-body strength (bilateral knee extensions) and power (countermovement jump [CMJ], squat jump [SJ], 30cm drop jump [DJ]) measures. The relationships between the variables were evaluated using eigenvector analysis and Pearson correlation analysis. Multiple linear regression revealed that the performance variables (10 and 20m speed, mean 505, and CoD deficit mean) can be predicted with almost 100% accuracy (i.e. adjusted R > 0.999) using various combinations of the predictor variables (DJ height, CMJ height, SJ height, lean body mass). An increase of one standard deviation (SD) in DJ height was associated with reductions of -5.636 and -9.082 SD in 10 m and 20 m sprint times. A one SD increase in CMJ also results in a reduction of -3.317 and -0.922 SD respectively in mean 505 and CoD deficit mean values. This study provides comparative data for professional English female soccer players that can be used by strength and conditioning coaches when monitoring player development and assessing the effectiveness of training programmes. Findings highlight the importance of developing reactive strength to improve speed and CoD ability in female soccer players.
The purpose of the current study was to investigate the anthropometric, body composition and fitness characteristics of female rugby league players by playing position. Data were collected on 27 players who were part of the English elite women's rugby league squad. Player assessments comprised anthropometric (stature and body mass), body composition (dual-energy X-ray absorptiometry) and fitness (lower-body power [countermovement jump (CMJ), 20 kg jump squat (JS) and 30 cm drop jump], 5, 10, 20, 30, and 40 m sprint, 505 agility, Yo-Yo intermittent recovery test level 1) measures. Players were classified into playing position (i.e., forwards and backs) prior to analysis. A multivariate analysis of variance (MANOVA) demonstrated significant (p<0.05) differences for body mass, stature, total fat, lean mass and percentage body fat between forwards and backs. Positional differences were also observed for speed, agility and lower-body power. Significant relationships were observed between total body fat and all fitness variables, and total lean mass was related to CMJ and JS peak power. This study provides comparative data for female rugby league forwards and backs. Body fat was strongly associated with performance and should therefore be considered in developing fitness characteristics. The relationship to match performance and trainability of these characteristics warrants further investigation.
PurposeThe purpose of this study was to examine the acute and chronic training responses to strength-, hypertrophy- and cluster-type resistance training.MethodsThirty-four trained males were assigned to a strength [STR: 4 × 6 repetitions, 85 % of one repetition maximum, (1RM), 900 s total rest], hypertrophy (HYP: 5 × 10 repetitions, 70 % 1RM, 360 s total rest), cluster 1 (CL-1: 4 × 6/1 repetitions, 85 % 1RM, 1400 s total rest), and cluster 2 (CL-2: 4 × 6/1 repetitions, 90 % 1RM, 1400 s total rest) regimens which were performed twice weekly for a 6-week period. Measurements were taken before, during and following the four workouts to investigate the acute training stimulus, whilst similar measurements were employed to examine the training effects before and after the intervention.ResultsThe improvements in 1RM strength were significantly greater for the STR (12.09 ± 2.75 %; p < 0.05, d = 1.106) and CL-2 (13.20 ± 2.18 %; p < 0.001, d = 0.816) regimens than the HYP regimen (8.13 ± 2.54 %, d = 0.453). In terms of the acute responses, the STR and CL-2 workouts resulted in greater time under tension (TUT) and impulse generation in individual repetitions than the HYP workout (p < 0.05). Furthermore, the STR (+3.65 ± 2.54 mmol/L−1) and HYP (+6.02 ± 2.97 mmol/L−1) workouts resulted in significantly greater elevations in blood lactate concentration (p < 0.001) than the CL-1 and CL-2 workouts.ConclusionCL regimens produced similar strength improvements to STR regimens even when volume load was elevated (CL-2). The effectiveness of the STR and CL-2 regimens underlines the importance of high loads and impulse generation for strength development.
The present study aimed to examine a wide profile of acute biochemical and neuromuscular responses to strength (STR) and hypertrophy (HYP) resistance exercise (RE). Seven trained males completed a STR workout (4 x 6 repetitions, 85% one repetition maximum [1RM], 5 min rest periods), a HYP workout (4 x 10 repetitions, 70% 1RM, 90s rest periods) and a control condition (CON) in a randomised cross-over design. Peak force (PF), rate of force development (RFD) and muscle activity were quantified pre-and post-exercise during an isometric squat protocol. Blood samples were taken 20, 10 and 0 minutes pre-and 0, 10 and 60 minutes post-exercise to measure the concentration of blood lactate (BL), pH and a number of electrolytes that were corrected for plasma volume changes.No differences were observed between the workouts for changes in PF, RFD or muscle activity.Repeated contrasts revealed a greater (p ≤0.05) increase in BL concentration and reduction in pH following the HYP protocol than the STR or CON conditions. There were similar but significant (p ≤0.05) changes in the concentration of a number of electrolytes following both workouts and a handful of these changes displayed significant correlations with the PF reductions observed following the HYP condition. Although the STR and HYP workouts were significantly different in terms of intensity, volume and rest, these differences were only observable in the acid-base responses. The present findings reinforce the need for practioners to look beyond the classification of RE workouts when aiming to elicit specific physiological responses.
The construction of the KAT-7 array in the Karoo region of the Northern Cape in South Africa was intended primarily as an engineering prototype for technologies and techniques applicable to the MeerKAT telescope. This paper looks at the main engineering and scientific highlights from this effort, and discusses their applicability to both MeerKAT and other next-generation radio telescopes. In particular we found that the composite dish surface works well, but it becomes complicated to fabricate for a dish lacking circular symmetry; the Stirling cycle cryogenic system with ion pump to achieve vacuum works but demands much higher maintenance than an equivalent Gifford-McMahon cycle system; the ROACH (Reconfigurable Open Architecture Computing Hardware)-based correlator with SPEAD (Streaming Protocol for Exchanging Astronomical Data) protocol data transfer works very well and KATCP (Karoo Array Telescope Control Protocol) control protocol has proven very flexible and convenient. KAT-7 has also been used for scientific observations where it has a niche in mapping low surface-brightness continuum sources, some extended HI halos and OH masers in star-forming regions. It can also be used to monitor continuum source variability, observe pulsars, and make VLBI observations.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.