No effect of HMB or α-HICA supplementation on training-induced changes in body composition

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?相似文献   

Sex differences and sex bias on the Boehm test of basic concepts: Do they exist?

Form A of the Boehm Test of Basic Concepts (BTBC) was administered to 180 kindergartners—90 boys and 90 girls. Neither their mean scores nor their standard deviations differed significantly, and the distributions of scores for the two groups were virtually identical. Moreover, the application of three internal criteria for bias yielded totally negative results; thus, there was no evidence of either sex differences or sex bias in the data.     

Mental health care for foster children in California

This paper reports on a study conducted to assess the health care needs of foster children in California. To evaluate foster children's mental health problems and the services provided to meet them, 154 program administrators, social workers, foster parents, and health care providers were interviewed in 14 counties. Foster parents and social workers were interviewed in groups, and foster parents and administrators also completed questionnaires. We found that although all counties care immediately for children who are injured, abused, or ill, only one county performs routine mental health evaluations of all children, and in most counties less than a third of children ever receive such evaluations. Informants identified mental health problems as more severe than medical problems in this population, and they identified four major barriers to access to appropriate therapy. Recommendations are that all children should receive comprehensive mental health evaluations, and procedures for immediate and ongoing care with consistent providers who are sensitive to foster children's needs should be included in case management plans, and covered by improved payment mechanisms. Additionally, communication, coordination and joint planning should be instituted among relevant agencies to address foster children's needs, and increased resources and training should be directed towards social service agencies and foster parents.     

Anthropometric dimensions of male powerlifters of varying body mass

In this study, we examined the anthropometric dimensions of powerlifters across various body mass (competitive bodyweight) categories. Fifty-four male Oceania competitive powerlifters (9 lightweight, 30 middleweight, and 15 heavyweight) were recruited from one international and two national powerlifting competitions held in New Zealand. Powerlifters were assessed for 37 anthropometric dimensions by ISAK (International Society for the Advancement of Kinanthropometry) level II and III accredited anthropometrists. The powerlifters were highly mesomorphic and had large girths and bony breadths, both in absolute units and when expressed as Z(p)-scores compared through the Phantom (Ross & Wilson, 1974). These anthropometric characteristics were more pronounced in heavyweights, who were significantly heavier, had greater muscle and fat mass, were more endo-mesomorphic, and had larger girths and bony breadths than the lighter lifters. Although middleweight and heavyweight lifters typically had longer segment lengths than the lightweights, all three groups had similar Zp-scores for the segment lengths, indicating similar segment length proportions. While population comparisons would be required to identify any connection between specific anthropometric dimensions that confer a competitive advantage to the expression of maximal strength, anthropometric profiling may prove useful for talent identification and for the assessment of training progression in powerlifting.     

Effects of dynamic upper-body exercise on lower-limb isometric endurance

Following preliminary indications that in some individuals arm exercise enhanced rather than reduced simultaneous leg endurance, ten young men and women performed three forms of intermittent work to volitional exhaustion, under duty cycles of 45 s work, 15 s rest. The protocols were as follows: (A) knee extensions at 30% maximum voluntary contraction (MVC); (B) 30% MVC knee extensions combined with arm cranking at 130% of their own lactate threshold; (C) combined 30% MVC knee extensions and arm cranking at 20% of their own lactate threshold. Heart rate, oxygen uptake (VO(2)), and blood lactate concentration were among the variables recorded throughout. All physiological indicators of demand were substantially higher in protocol B than in protocols A or C [heart rate: (A) 154 beats . min(-1), (B) 171 beats . min(-1), (C) 150 beats . min(-1); VO(2): (A) 11.9 ml . kg(-1) . min(-1), (B) 21.7 ml . kg(-1) . min(-1), (C) 14.2 ml . kg(-1) . min(-1); blood lactate concentration: (A) 3.3 mmol . l(-1), (B) 5.1 mmol . l(-1), (C) 2.8 mmol . l(-1)], yet there were no significant differences (P > 0.05) in the endurance times between the three conditions [(A) 11.43 min, (B) 11.1 min, (C) 10.57 min] and seven participants endured longest in protocol B. Results from protocol (C) cast doubt on explanations in terms of psychological distraction. We suggest that lactic acid produced by the arms is shuttled to the legs and acts there either as a supplementary fuel source or as an antagonist to the depressing effects of increased potassium concentration.     

The human genome and sport, including epigenetics and athleticogenomics: a brief look at a rapidly changing field

Since Hugh Montgomery discovered the first of what are now nearly 200 "fitness genes", together with rapid advances in human gene therapy, there is now a real prospect of the use of genes, genetic elements, and/or cells that have the capacity to enhance athletic performance (to paraphrase the World Anti-Doping Agency's definition of gene doping). This overview covers the main areas of interface between genetics and sport, attempts to provide a context against which gene doping may be viewed, and suggests a futuristic legitimate use of genomic (and possibly epigenetic) information in sport.