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971.
Filipe J. Teixeira Catarina N. Matias Cristina P. Monteiro Maria J. Valamatos Joana F. Reis Ana Batista 《European Journal of Sport Science》2019,19(6):802-810
β-hydroxy-β-methylbutyrate (calcium: HMB-Ca and free acid: HMB-FA) and α-hydroxyisocaproic acid (α-HICA) are leucine metabolites that have been proposed to improve body composition and strength when combined with resistance exercise training (RET). In this double-blind randomized controlled pragmatic trial, we evaluated the effects of off-the-shelf supplements: α-HICA, HMB-FA and HMB-Ca, on RET-induced changes in body composition and performance. Forty men were blocked randomized to receive α-HICA (n?=?10, fat-free mass [FFM]?=?62.0?±?7.1?kg), HMB-FA (n?=?11, FFM?=?62.7?±?10.5?kg), HMB-Ca (n?=?9, FFM?=?65.6?±?10.1?kg) or placebo (PLA; n?=?10, FFM?=?64.2?±?5.7?kg). The training protocol consisted of a whole-body resistance training routine, thrice weekly for 8 weeks. Body composition was assessed by dual-energy x-ray absorptiometry (DXA) and total body water (TBW) by whole-body bioimpedance spectroscopy (BIS), both at baseline and at the end of weeks 4 and 8. Time-dependent changes were observed for increase in trunk FFM (p?0.05). No statistically significant between-group or group-by-time interactions were observed. Supplementation with HMB (FA and Ca) or α-HICA failed to enhance body composition to a greater extent than placebo. We do not recommend these leucine metabolites for improving body composition changes with RET in young adult resistance trained men. 相似文献
972.
973.
Wrist movements have been identified as an important factor in producing a successful golf swing, with their complex motion influencing both club head velocity and orientation. However, a detailed analysis of wrist angles is lacking in the literature. The purpose of this study was to determine kinematics across wrists and club head characteristics during the golf swing under weak, neutral and strong grip conditions. Twelve professional male golfers executed 24 shots using a driver under three grip conditions. A six degrees of freedom analysis of the hand with respect to the distal forearm was performed using a 10-camera three-dimensional motion capture system. Differences in joint angles were explored using repeated measures ANOVAs at key swing events (onset, top of backswing and impact), in addition club head velocity and clubface angle at impact were also explored. Main findings revealed significant differences in flexion/extension and internal/external rotation for both wrists at all swing events, whereas fewer significant interactions were found in ulnar/radial deviation across grips for both wrists at all events. Clubface angle only differed significantly between the weak and the strong and neural grips, presenting a more ‘open’ clubface to the intended hitting direction. This study is the first to explore tri-planar wrist movement and the effect of different grips, such analysis has implications for coaching knowledge and practice and should inform future research into different aspects of skill, technique analysis and may inform injury mechanisms/prevention. 相似文献
974.
Chanwoo Park 《Sport in Society》2019,22(8):1346-1361
AbstractThe purpose of the current study is to uncover the meanings that constitute a good father within the context of a sports/leisure setting and to analyse how these meanings are enacted in practice. Results showed that the ‘good father’ of today, as perceived by fathers, is a multifaceted construct that is construed through their interactions with other family members. First, fathers constructed the meanings of a good father through the memories of their own fathers during their childhood. Second, fathers constructed the meanings through their relationship with their wives. They regarded sport parenting as an important practice for them to be a good husband to their wives. Finally, fathers constructed the meanings of a good father through their relationships with their children and the time spent with their children was a particularly important requirement for them to fulfil their role as a good father. 相似文献
975.
976.
977.
The objective of this study was to examine current teacher and mental health professional ratings regarding the relative seriousness of 50 specific children's behavior problems and to compare the results to those found by Wickman (1928). Wickman's questionnaire and procedures were replicated to insure comparability. A second objective was to extend Wickman's work so that children's ratings of their own behavior problems may be ascertained. An increase in the similarity between teachers' and mental health professionals' judgements concerning the seriousness of specific children's behavior problems was found. These findings were attributable to a more pragmatic approach taken by mental health professionals. A very high agreement on the seriousness of specific behavior problem ratings was demonstrated by children and teachers. This similarity may be the result of proximity of effects. 相似文献
978.
The Behavior Problem Checklist (Quay & Peterson, 1979) was completed by classroom teachers for 104 children and youth (64 boys and 40 girls) at a state residential school for the blind to determine the prevalence of problem behavior. Results were compared to earlier studies of behavior problems of nonhandicapped children and of two groups of hearing-impaired children, one living at home and attending a community program and a second group attending a state residential school. Results were more similar to those obtained with the hearing-impaired children in the residential setting than to either the nonhandicapped or the hearing-impaired living at home. Comparisons by sex failed to find statistically significant differences. 相似文献
979.
This study investigated the interscorer reliability between a novice and a professional psychologist for the Minnesota Percepto-Diagnostic Test-Revised (MPDT-R). The sample consisted of 30 individuals (18 males and 12 females) who were referred to the Applied Neuroscience Institute of the University of Maryland Eastern Shore. Results from the study indicated that for three of the four MPDT-R scores there was a significant positive correlation between expert and novice scoring criteria. Implications for the assessment of perceptual-motor problems using the MPDT-R are discussed. 相似文献
980.
Ernest A. Collabolletta Allen J. Fossbender Thomas Edward Bratter 《Psychology in the schools》1983,20(4):450-455
Before choosing to become involved with students who currently are abusing psychoactive substances, teachers must consider not only the potential consequences and payoffs to them professionally, but also what specifically they can do to help adolescents. This article presents some of the philosophical problems, and suggests potential solutions of how to relate to students who engage in potentially self-destructive, drug-related behavior. There is a need for teachers to become quasi-counselors and consultants, since they are the first line of defense against substance use and abuse. 相似文献