ABSTRACT
The effect of two soccer-training seasons on the growth, development and somatotype hormone concentrations of elite youth soccer players were evaluated. Eighteen elite soccer players and 18 age-matched non-athletic control subjects participated in the study. Anthropometric-measurements, aerobic and anaerobic performance tests and serum concentrations of insulin-like growth factor-1 (IGF-1), insulin-like growth factor binding protein-3 (IGFBP-3), and growth hormone (GH) were assessed at 5 time points across two competitive seasons. Soccer players revealed higher GH, IGF-1 and IGFBP-3 than the control group across all-time points. Significant moderate correlations were observed only in soccer players between hormonal concentrations (IGF-1 and IGFBP-3) and the jumping tests (r = 0.45-0.48; p < 0.01). Somatotropic axis hormones, anthropometric and physical parameters increased to a greater degree with growth and soccer training combined compared to growth alone. Results from this investigation revealed that intense training did not impair growth or development in these young soccer players across 2-year period.
Subject(s)
Human Growth Hormone/blood , Insulin-Like Growth Factor Binding Protein 3/blood , Insulin-Like Growth Factor I/analysis , Physical Conditioning, Human , Physical Fitness , Somatotypes , Adolescent , Anthropometry , Athletes , Humans , Male , SoccerABSTRACT
Healthcare-associated infections (HAIs) are the infections that patients get while receiving medical treatment in a medical facility with bacterial HAIs being the most common. Silver and gold nanoparticles (NPs) have been successfully employed as antibacterial motifs; however, NPs leaching in addition to poor dispersion and overall reproducibility are major hurdles to further product development. In this study, the authors design and fabricate a smart antibacterial mixed-matrix membrane coating comprising colloidal lysozyme-templated gold nanoclusters as nanofillers in poly(ethylene oxide)/poly(butylene terephthalate) amphiphilic polymer matrix. Mesoporous silica nanoparticles-lysozyme functionalized gold nanoclusters disperse homogenously within the polymer matrix with no phase separation and zero NPs leaching. This mixed-matrix coating can successfully sense and inhibit bacterial contamination via a controlled release mechanism that is only triggered by bacteria. The system is coated on a common radiographic dental imaging device (photostimulable phosphor plate) that is prone to oral bacteria contamination. Variation and eventually disappearance of the red fluorescence surface under UV light signals bacterial infection. Kanamycin, an antimicrobial agent, is controllably released to instantly inhibit bacterial growth. Interestingly, the quality of the images obtained with these coated surfaces is the same as uncoated surfaces and thus the safe application of such smart coatings can be expanded to include other medical devices without compromising their utility.
Subject(s)
Bacterial Infections , Coated Materials, Biocompatible , Gold Colloid , Kanamycin , Muramidase , Nanoparticles/chemistry , Silicon Dioxide , Bacterial Infections/diagnosis , Bacterial Infections/drug therapy , Coated Materials, Biocompatible/chemistry , Coated Materials, Biocompatible/pharmacology , Delayed-Action Preparations/chemistry , Delayed-Action Preparations/pharmacology , Gold Colloid/chemistry , Gold Colloid/pharmacology , Humans , Kanamycin/chemistry , Kanamycin/pharmacology , MCF-7 Cells , Muramidase/chemistry , Muramidase/pharmacology , Silicon Dioxide/chemistry , Silicon Dioxide/pharmacologyABSTRACT
The aim of this study was to examine the validity and reliability of the Loughborough Soccer Passing Test (LSPT) in adolescent soccer players. Eighty-seven players, aged 14-17 years, were recruited according to their playing level: elite (n = 44), sub-elite (n = 22), and non-elite (n = 21). Two attempts of the LSPT were performed at baseline. Players then completed 10 attempts over 3 weeks to familiarize themselves with the test. Subsequently, 2 main trials, separated by 1 week, were performed; the mean of the 2 attempts was recorded as the performance score. After familiarization, the performance scores showed significant differences (p < 0.01) between elite (40.3 ± 8.3 seconds), sub-elite (58.1 ± 10.2 seconds), and non-elite players (66.6 ± 11.7 seconds). There was low-to-moderate reliability between trials with sub-elite (r = 0.35, p < 0.05) and non-elite players (r = 0.47, p < 0.05), but very good for elite players (r = 0.96, p < 0.05). Scores at baseline were better (p < 0.05) for elite players (51.0 ± 9.3 seconds) compared with sub-elite (60.8 ± 8.2 seconds) and non-elite players (69.0 ± 11.1 seconds). The LSPT seems to be a valid and reliable protocol to assess differences in soccer skill performance in adolescent players and can distinguish players according to their playing level. The LSPT was able to distinguish different abilities without players undergoing any familiarization with the test, thus enabling it to be used for talent identification purposes.
