142 research outputs found

    An analysis of the physical demands of international female soccer match-play and the physical characteristics of elite players

    Get PDF
    The purpose of the thesis was to provide a detailed analysis of the physical demands of competitive international female soccer match-play and the physical characteristics of elite players. To date, the majority of research has focussed on sub-elite players with a lack of information available on international level competitors. The aim of the first study (Chapter 4) was to analyse match physical performance using a computerised tracking system (Prozone Sports Ltd., Leeds, England). A total of 167 individual match observations from 122 players competing in competitive international matches during the 2011-2012 and 2012-2013 seasons were completed. Total distance and total high-speed running distances (>14.4 km.h-1) were influenced by outfield playing position, with central midfielders completing the highest (10985 ± 706 m and 2882 ± 500 m) and central defenders (9489 ± 562 m and 1901 ± 268 m) the lowest distances, respectively. Greater total very high-speed running distances (>19.8 km.h-1) were completed when a team was without (399 ± 143 m) compared to with (313 ± 210 m) possession of the ball. The majority of sprints (>25.1 km.h-1) were over short distances with 95 % being less than 10 m. This study provides novel findings regarding the physical demands of different playing positions in competitive international female match-play and important insights for physical coaches preparing elite female players for competition. The aim of the second study (Chapter 5) was to determine the incidence and nature of repeated sprint and high-speed activity in match-play. Repeated sprint activity (a minimum of two efforts (>25.1 km.h-1) with 20 s or less recovery between efforts) was found to be rare during international female match-play with 1.1 ± 1.1 bouts per match. Repeated high-speed activity (a minimum of two efforts (>19.8 km.h-1) was influenced by playing position; with attacking-based players completing more bouts (37-40 bouts per match) than defensive players (22-33 bouts per match). Repeated sprint and high-speed bouts frequently comprised two efforts per bout, with a maximum of three and six efforts respectively. Collectively, this study provides physical coaches with useful data for replicating the demands of repeated high-speed activity and an understanding of the positional demands in order to aid the specificity of training. The aim of the third study (Chapter 6) was to attempt to apply a suitable approach for determining speed zones and to evaluate the application of specific zones to influence data outcome. Maximum match-play running speed in elite females was measured using Global Positioning System technology (STATSports, Viper, Ireland) in 230 individual match observations of 67 outfield players, during 19 international matches from 2011-2015. Female-specific speed zones and activity classifications were scaled appropriately to maximum match-play running speed. The resultant female-specific speed zones were on average 12.5 % lower than the standardised male zones, which if applied to the data in Chapter 4 would result in a small increases in total high-speed running (25 % to 28 %) and total very high-speed running (8 % to 9 %) relative to total distance. The calculated female-specific sprinting threshold (>22.0 km.h-1) corresponds to 82 % of the average maximum female match-play running speed presently observed and consequently might be more representative than the standardised male sprinting threshold (>25.1 km.h-1). However, as it was not possible to validate activity classifications in the current study it is suggested that the standardised thresholds should continue to be used to permit between playing position and gender comparisons, however, the activity classifications (e.g. walking, jogging, sprinting etc.) should be removed and replaced with the actual velocities. The aim of the fourth study (Chapter 7) was to examine the reliability of both anthropometric and performance measures in elite female soccer players. The data suggest that both junior and senior elite female players are able to adequately reproduce a variety of anthropometric (coefficient of variation = 0.1-1.3 %) and performance (coefficient of variation = 0.6-7.7 %) related tests and that reliable measures can be obtained using the present protocols and one familiarisation session. The sample size estimations (n<20) provided important insights for the participant recruitment in Chapter 8 and also suggest that the anthropometric and performance assessments are suitable for the longitudinal tracking of the fitness status of elite female players. The aim of the fifth study (Chapter 8) was to examine the physical characteristics of elite players, which were assessed in 471 national team players from 2011-2015. Anthropometric and performance variables improved with age; with large differences observed between U15s and seniors for body mass (53.9 ± 7.8 v 62.5 ± 5.8 kg), 30 m linear speed (4.78 ± 0.22 v 4.52 ± 0.17 s), countermovement jump (28.3 ± 4.0 cm v 33.4 ± 4.0 cm) and Yo Yo Intermittent Recovery Test Level 1 (1101 ± 369 m v 1583 ± 416 m). Similarities were observed for anthropometric and performance variables between the younger (U15 and U17) and older (U19 and senior) age groups. Goalkeepers generally exhibited inferior anthropometric and performance capabilities to outfield players. Faster linear speed times over short distances observed were in attackers (1.047 s v 1.061-1.077 s), greater repeated speed performance in wide midfielders and attackers (4.89-4.91 s v 4.92-4.99 s) and improved intermittent endurance performance in wide defenders (1483 m v 1260-1336 m) compared to other outfield playing positions. The normative physical characteristics presented, provide unique data for professionals involved in player recruitment and talent identification, whilst the positional differences in performance characteristics, coupled with an in-depth understanding of the demands of match-play can be applied to ensure training specificity. Collectively, the present data provides the most in-depth description of the physical demands and physical characteristics of elite female soccer players to date. The data describing the demands of match-play provides valuable insights for physical coaches preparing elite female players for competition, whilst the normative physical characteristic data provides important information to professionals involved in player recruitment and talent identification and those responsible for physical development

    High-intensity endurance capacity assessment as a tool for talent identification in elite youth female soccer.

    Get PDF
    Talent identification and development programmes have received broad attention in the last decades, yet evidence regarding the predictive utility of physical performance in female soccer players is limited. Using a retrospective design, we appraised the predictive value of performance-related measures in a sample of 228 youth female soccer players previously involved in residential Elite Performance Camps (age range: 12.7-15.3 years). With 10-m sprinting, 30-m sprinting, counter-movement jump height, and Yo-Yo Intermittent Recovery Test Level 1 (IR1) distance as primary predictor variables, the Akaike Information Criterion (AIC) assessed the relative quality of four penalised logistic regression models for determining future competitive international squads U17-U20 level selection. The model including Yo-Yo IR1 was the best for predicting career outcome. Predicted probabilities of future selection to the international squad increased with higher Yo-Yo IR1 distances, from 4.5% (95% confidence interval, 0.8 to 8.2%) for a distance lower than 440 m to 64.7% (95% confidence interval, 47.3 to 82.1%) for a score of 2040 m. The present study highlights the predictive utility of high-intensity endurance capacity for informing career progression in elite youth female soccer and provides reference values for staff involved in the talent development of elite youth female soccer players

    Paired hormone response elements predict caveolin-1 as a glucocorticoid target gene

    Get PDF
    Abstract Glucocorticoids act in part via glucocortocoid receptor binding to hormone response elements (HREs), but their direct target genes in vivo are still largely unknown. We developed the criterion that genomic occurrence of paired HREs at an inter-HRE distance less than 200 bp predicts hormone responsiveness, based on synergy of multiple HREs, and HRE information from known target genes. This criterion predicts a substantial number of novel responsive genes, when applied to genomic regions 10 kb upstream of genes. Multiple-tissue in situ hybridization showed that mRNA expression of 6 out of 10 selected genes was induced in a tissue-specific manner in mice treated with a single dose of corticosterone, with the spleen being the most responsive organ. Caveolin-1 was strongly responsive in several organs, and the HRE pair in its upstream region showed increased occupancy by glucocorticoid receptor in response to corticosterone. Our approach allowed for discovery of novel tissue specific glucocorticoid target genes, which may exemplify responses underlying the permissive actions of glucocorticoids

    A gene-rich linkage map in the dioecious species Actinidia chinensis (kiwifruit) reveals putative X/Y sex-determining chromosomes

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>The genus <it>Actinidia </it>(kiwifruit) consists of woody, scrambling vines, native to China, and only recently propagated as a commercial crop. All species described are dioecious, but the genetic mechanism for sex-determination is unknown, as is the genetic basis for many of the cluster of characteristics making up the unique fruit. It is, however, an important crop in the New Zealand economy, and a classical breeding program would benefit greatly by knowledge of the trait alleles carried by both female and male parents. The application of marker assisted selection (MAS) in seedling populations would also aid the accurate and efficient development of novel fruit types for the market.</p> <p>Results</p> <p>Gene-rich female, male and consensus linkage maps of the diploid species <it>A. chinensis </it>have been constructed with 644 microsatellite markers. The maps consist of twenty-nine linkage groups corresponding to the haploid number n = 29. We found that sex-linked sequence characterized amplified region (SCAR) markers and the 'Flower-sex' phenotype consistently mapped to a single linkage group, in a subtelomeric region, in a section of inconsistent marker order. The region also contained markers of expressed genes, some of unknown function. Recombination, assessed by allelic distribution and marker order stability, was, in the remainder of the linkage group, in accordance with other linkage groups. Fully informative markers to other genes in this linkage group identified the comparative linkage group in the female map, where recombination ratios determining marker order were similar to the autosomes.</p> <p>Conclusion</p> <p>We have created genetic linkage maps that define the 29 linkage groups of the haploid genome, and have revealed the position and extent of the sex-determining locus in <it>A. chinensis</it>. As all <it>Actinidia </it>species are dioecious, we suggest that the sex-determining loci of other <it>Actinidia </it>species will be similar to that region defined in our maps. As the extent of the non-recombining region is limited, our result supports the suggestion that the subtelomeric region of an autosome is in the early stages of developing the characteristics of a sex chromosome. The maps provide a reference of genetic information in <it>Actinidia </it>for use in genetic analysis and breeding programs.</p

    VLT/X-shooter spectroscopy of the afterglow of the Swift GRB 130606A: Chemical abundances and reionisation at z∼6z\sim6

    Get PDF
    The reionisation of the Universe is thought to have ended around z~6, as inferred from spectroscopy of distant bright background sources, such as quasars (QSO) and gamma-ray burst (GRB) afterglows. Furthermore, spectroscopy of a GRB afterglow provides insight in its host galaxy, which is often too dim and distant to study otherwise. We present the high S/N VLT/X-shooter spectrum of GRB130606A at z=5.913. We aim to measure the degree of ionisation of the IGM between 5.02<z<5.84 and to study the chemical abundance pattern and dust content of its host galaxy. We measured the flux decrement due to absorption at Lyα\alpha, β\beta and γ\gamma wavelength regions. The hydrogen and metal absorption lines formed in the host galaxy were fitted with Voigt profiles to obtain column densities. Our measurements of the Lyα\alpha-forest optical depth are consistent with previous measurements of QSOs, but have a much smaller uncertainty. The analysis of the red damping wing yields a neutral fraction xHI<0.05x_{HI}<0.05 (3σ\sigma). We obtain column density measurements of several elements. The ionisation corrections due to the GRB is estimated to be negligible (<0.03 dex), but larger corrections may apply due to the pre-existing radiation field (up to 0.4 dex based on sub-DLA studies). Our measurements confirm that the Universe is already predominantly ionised over the redshift range probed in this work, but was slightly more neutral at z>5.6. GRBs are useful probes of the ionisation state of the IGM in the early Universe, but because of internal scatter we need a larger statistical sample to draw robust conclusions. The high [Si/Fe] in the host can be due to dust depletion, alpha-element enhancement, or a combination of both. The very high value of [Al/Fe]=2.40+/-0.78 might connected to the stellar population history. We estimate the host metallicity to be -1.7<[M/H]<-0.9 (2%-13% of solar). (trunc.)Comment: 15 pages, 12 figure

    Report of a TREAT-NMD/World Duchenne Organisation Meeting on Dystrophin Quantification Methodology

    Get PDF
    Representatives of academia, patient organisations, industry and the United States Food and Drug Administration attended a workshop on dystrophin quantification methodology. The aims of the workshop were to provide an overview of methods used to quantify dystrophin levels in human skeletal muscle and their applicability to clinical trial samples, outline the gaps with regards to validating the methods for robust clinical applications prior to regulatory agency review, and to align future efforts towards further optimizing these methods. The workshop facilitated a constructive but also critical discussion on the potential and limitations of techniques currently used in the field of translational research (western blot and immunofluorescence analysis) and emerging techniques (mass spectrometry and capillary western immunoassay). Notably, all participants reported variation in dystrophin levels between muscle biopsies from different healthy individuals and agreed on the need for a common reference sample

    The psychological and social impact of the digital self-support system ‘Brain in Hand’ on autistic people: prospective cohort study in England and Wales

    Get PDF
    Background Brain in Hand (BIH) is a UK-based digital self-support system for managing anxiety and social functioning. Aims To identify the impact of BIH on the psychological and social functioning of adults with autism. Method Adults with diagnosed or suspected DSM-5 (level 1) autism, identified by seven NHS autism services in England and Wales, were recruited for a 12-week prospective mixed-methods cohort study. The primary quantitative outcome measures were the Health of the Nation Outcome Scales for People with Learning Disabilities (HONOS-LD) and the Hospital Anxiety and Depression Scale (HADS). Fisher's exact test explored sociodemographic associations. Paired t-test was utilised for pre–post analysis of overall effectiveness of BIH. Multivariable linear regression models, univariable pre–post analysis, Wilcoxon signed-rank test, logistic regression analysis, Bonferroni correction and normative analysis were used to give confidence in changes identified. A thematic analysis of semi-structured exist interviews following Braun and Clarke's six-step process of 10% of participants who completed the study was undertaken. Results Sixty-six of 99 participants completed the study. There was significant reduction in mean HONOS-LD scores, with 0.65 s.d. decrease in those who used BIH for 12 weeks. Significant positive changes were identified in HONOS-LD subdomains of ‘self-injurious behaviours’, ‘memory and orientation’, ‘communication problems in understanding’, ‘occupation and activities’ and ‘problems with relationship’. A significant reduction in the anxiety, but not depression, component of the HADS scores was identified. Thematic analysis showed high confidence in BIH. Conclusions BIH improved anxiety and other clinical, social and functioning outcomes of adults with autism. </jats:sec

    Oxygen uptake kinetics in trained adolescent females

    Get PDF
    Little evidence exists with regard to the effect that exercise training has upon oxygen uptake kinetics in adolescent females. PURPOSE: The aim of the study was to compare [Formula: see text] and muscle deoxygenation kinetics in a group of trained (Tr) and untrained (Utr) female adolescents. METHOD: Twelve trained (6.4 ± 0.9 years training, 10.3 ± 1.4 months per year training, 5.2 ± 2.0 h per week) adolescent female soccer players (age 14.6 ± 0.7 years) were compared to a group (n = 8) of recreationally active adolescent girls (age 15.1 ± 0.6 years) of similar maturity status. Subjects underwent two, 6-min exercise transitions at a workload equivalent to 80 % of lactate threshold from a 3-min baseline of 10 W. All subjects had a passive rest period of 1 h between each square-wave transition. Breath-by-breath oxygen uptake and muscle deoxygenation were measured throughout and were modelled via a mono-exponential decay with a delay relative to the start of exercise. RESULT: Peak [Formula: see text] was significantly (p < 0.05) greater in the Tr compared to the Utr (Tr: 43.2 ± 3.2 mL kg(-1 )min(-1) vs. Utr: 34.6 ± 4.0 mL kg(-1 )min(-1)). The [Formula: see text] time constant was significantly (p < 0.05) faster in the Tr compared to the Utr (Tr: 26.3 ± 6.9 s vs. Utr: 35.1 ± 11.5 s). There was no inter-group difference in the time constant for muscle deoxygenation kinetics (Tr: 8.5 ± 3.0 s vs. Utr: 12.4 ± 8.3 s); a large effect size, however, was demonstrated (-0.804). CONCLUSION: Exercise training and/or genetic self-selection results in faster kinetics in trained adolescent females. The faster [Formula: see text] kinetics seen in the trained group may result from enhanced muscle oxygen utilisation

    Localization of Mineralocorticoid Receptors at Mammalian Synapses

    Get PDF
    In the brain, membrane associated nongenomic steroid receptors can induce fast-acting responses to ion conductance and second messenger systems of neurons. Emerging data suggest that membrane associated glucocorticoid and mineralocorticoid receptors may directly regulate synaptic excitability during times of stress when adrenal hormones are elevated. As the key neuron signaling interface, the synapse is involved in learning and memory, including traumatic memories during times of stress. The lateral amygdala is a key site for synaptic plasticity underlying conditioned fear, which can both trigger and be coincident with the stress response. A large body of electrophysiological data shows rapid regulation of neuronal excitability by steroid hormone receptors. Despite the importance of these receptors, to date, only the glucocorticoid receptor has been anatomically localized to the membrane. We investigated the subcellular sites of mineralocorticoid receptors in the lateral amygdala of the Sprague-Dawley rat. Immunoblot analysis revealed the presence of mineralocorticoid receptors in the amygdala. Using electron microscopy, we found mineralocorticoid receptors expressed at both nuclear including: glutamatergic and GABAergic neurons and extra nuclear sites including: presynaptic terminals, neuronal dendrites, and dendritic spines. Importantly we also observed mineralocorticoid receptors at postsynaptic membrane densities of excitatory synapses. These data provide direct anatomical evidence supporting the concept that, at some synapses, synaptic transmission is regulated by mineralocorticoid receptors. Thus part of the stress signaling response in the brain is a direct modulation of the synapse itself by adrenal steroids

    Longitudinal analyses of the DNA methylome in deployed military servicemen identify susceptibility loci for post-traumatic stress disorder

    Get PDF
    In order to determine the impact of the epigenetic response to traumatic stress on post-traumatic stress disorder (PTSD), this study examined longitudinal changes of genome-wide blood DNA methylation profiles in relation to the development of PTSD symptoms in two prospective military cohorts (one discovery and one replication data set). In the first cohort consisting of male Dutch military servicemen (n=93), the emergence of PTSD symptoms over a deployment period to a combat zone was significantly associated with alterations in DNA methylation levels at 17 genomic positions and 12 genomic regions. Evidence for mediation of the relation between combat trauma and PTSD symptoms by longitudinal changes in DNA methylation was observed at several positions and regions. Bioinformatic analyses of the reported associations identified significant enrichment in several pathways relevant for symptoms of PTSD. Targeted analyses of the significant findings from the discovery sample in an independent prospective cohort of male US marines (n=98) replicated the observed relation between decreases in DNA methylation levels and PTSD symptoms at genomic regions in ZFP57, RNF39 and HIST1H2APS2. Together, our study pinpoints three novel genomic regions where longitudinal decreases in DNA methylation across the period of exposure to combat trauma marks susceptibility for PTSD
    • …
    corecore