Background: The study of the relationship between anthropometry and visceral adipose tissue (VAT) is of great interest because VAT is associated with many risk factors for noncommunicable diseases and anthropometry is easy to perform in clinical practice. The studies hitherto available for children have, however, been performed on small sample sizes. Design: Pooling of the data of studies published from 1992 to 2004 as indexed on Medline. Aims: To assess the relationship between anthropometry and VAT and subcutaneous adipose tissue (SAT) as measured by magnetic resonance imaging (MRI) in children and to analyze the effect of age, gender, pubertal status and ethnicity. Subjects and methods: Eligible subjects were 7-16 year-old, with availability of VAT and SAT, gender, ethnicity, body mass index (BMI) and waist circumference (WC). A total of 497 subjects were collected from seven different investigators and 407 of them (178 Caucasians and 229 Hispanics) were analyzed. Results: Despite ethnic differences in MRI data, BMI, WC and age, no difference in VAT was found between Caucasians and Hispanics after correction for SAT and BMI. Univariate regression analysis identified WC as the best single predictor of VAT (64.8% of variance) and BMI of SAT (88.9% of variance). The contribution of ethnicity and gender to the unexplained variance of the VAT-WC relationship was low (p3%) but significant (Pp0.002). The different laboratories explained a low (p4.8%) but significant (Po0.0001) portion of the unexplained variance of the VAT-WC and SAT-BMI relationships. Prediction equations for VAT (VAT (cm 2 ) ¼ 1.1 Â WC (cm)À52.9) and SAT (SAT (cm 2 ) ¼ 23.2 Â BMI (kg/m 2 )À329) were developed on a randomly chosen half of the population and crossvalidated in the remaining half. The pure error of the estimate was 13 cm 2 for VAT and 57 cm 2 for SAT. Conclusions: WC can be considered a good predictor of VAT as well as BMI of SAT. The importance of ethnicity and gender on VAT estimation is not negligible.

The purpose of this study was to investigate seasonal variations in physiological fitness of semiprofessional soccer players over a 12-month period. Thirteen male players were tested 5 times over a 12-month period using bioelectrical impedance, a 20-m multistage fitness test, countermovement standing vertical jump, 15-m sprint test, Illinois agility test, and sit and reach test. Significant deconditioning was apparent in all fitness variables from end of season one season to prepreseason training of the next season. Aerobic fitness, vertical jump, percent body fat, agility, and sprint performance improved from prepreseason to midseason. Significant decreases in aerobic fitness and the cessation of significant increases in vertical jump, sprint, and agility performance were shown from midseason onward. No differences between the fitness components at the end of season one and the end of season two were identified. The deconditioning apparent in all fitness parameters during the off season, together with progressive improvement in most from postpreseason to midseason would support these parameters as sport-specific fitness requirements. Such improvements suggest that the short-term demands of playing and training in the first half of the season develop fitness and these trends are similar to those for professional players. Body fat was also shown to be detrimental to sprint performance throughout the 12-month period. Further research is needed to identify if the plateau in fitness from midseason is the result of attaining the required level of fitness, fatigue, allied training, or even relative success. Enhancing off-season training may enable yearly fitness increases by at least maintaining fitness levels for the next year's preseason.

In the scientific literature, there is much evidence of a relationship between age and dexterity, where increased age is related to slower, less nimble and less smooth, less coordinated and less controlled performances. While some suggest that the relationship is a direct consequence of reduced muscle strength associated to increased age, there is a lack of research that has systematically investigated the relationships between age, strength and hand dexterity. Therefore, the aim of this study was to examine the associations between age, grip strength and dexterity. 107 adults (range 18-93 years) completed a series of hand dexterity tasks (i.e. steadiness, line tracking, aiming, and tapping) and a test of maximal grip strength. We performed three phases of analyses. Firstly, we evaluated the simple relationships between pairs of variables; replicating the existing literature; and found significant relationships of increased age and reduced strength; increased age and reduced dexterity, and; reduced strength and reduced dexterity. Secondly, we used standard Multiple Regression (MR) models to determine which of the age and strength factors accounted for the greater variance in dexterity. The results showed that both age and strength made significant contributions to the data variance, but that age explained more of the variance in steadiness and line tracking dexterity, whereas strength explained more of the variance in aiming and tapping dexterity. In a third phase of analysis, we used MR analyses to show an interaction between age and strength on steadiness hand dexterity. Simple Slopes post-hoc analyses showed that the interaction was explained by the middle to older aged adults showing a relationship between reduced strength and reduced hand steadiness, whereas younger aged adults showed no relationship between strength and steadiness hand dexterity. The results are discussed in terms of how age and grip strength predict different types of hand dexterity in adults.

Objective: To describe abdominal adipose tissue distribution in a large sample of contemporary British children; to determine the influence of gender, stage of maturation and body mass index (BMI) on abdominal adipose tissue distribution; and to compare the ability of BMI and waist circumference to predict abdominal adipose tissue. Subjects and methods: A total of 74 boys (mean age 13.4±0.4 years) and 96 girls (mean age 13.5±0.5 years) were selected from volunteer children enrolled in the Avon Longitudinal Study of Parents and Children (ALSPAC). Height, weight and waist circumference were measured and BMI calculated. Stage of sexual maturation was available for 113 children using a self-report questionnaire based on Tanner's criteria. Magnetic resonance imaging was used to assess subcutaneous abdominal adipose tissue (SAAT) and intra-abdominal adipose tissue (IAAT) volumes and patterning. Results: Boys had lower levels of IAAT (P ¼ 0.036) and SAAT (P ¼ 0.003) than girls. IAAT and SAAT were higher in overweight and obese boys and girls when compared with normal weight children (Po0.0001). This pattern was also reflected in waist circumference groups. Boys had higher IAAT/SAAT ratios than girls, indicating proportionately more adipose tissue deposited intra-abdominally (P ¼ 0.002). However, both boys and girls deposited less than 10% of their abdominal fat as internal adipose tissue. WC predicted 67.4% of the variance in IAAT (Po0.001), and BMI predicted 84.8% of the variance in SAAT (Po0.001). However, BMI as the best single predictor explained only 8.4% of the variance in the IAAT/SAAT ratio (Po0.001). Conclusions: At this age and stage of sexual maturation, the amount of IAAT remains relatively small. WC and BMI offer a feasible alternative to the MRI estimation of IAAT and SAAT, respectively, in a population-based sample of boys and girls.

OBJECTIVE: To determine the patterns of change and the best anthropometric indicators of intra-abdominal fat deposition in young adolescents from ages 11 ± 13 y. SUBJECTS: Subjects were 25 boys (mean age 13.7 AE 0.32 y) and 17 girls (mean age of 13.7 AE 0.23 y) who had taken part in a similar study 2 y earlier at ages 11.5 AE 0.33 y and 11.5 AE 0.27 y, respectively. METHODS: Intra-abdominal (IA) and subcutaneous adipose (SA) tissue areas and IAaSA ratio were determined through four tranverse magnetic resonance imaging scans on two occasions. Differences were investigated using t-tests and ANOVA. Skinfolds, girths and circumferences, body mass index and hydrostatic weighing were also recorded. Pearson correlation coef®cients and regression equations were calculated to determine the best anthropometric indicators of intra-abdominal fat deposition. RESULTS: Intra-abdominal fat and subcutaneous fat areas had signi®cantly increased in boys and girls by the second measure. Boys had deposited greater amounts of fat in intra-abdominal depots so that their intra-abdominalasubcutaneous ratio had increased signi®cantly from 0.31 to 0.39. This had reduced in girls from 0.39 to 0.35. However, patterns of change were variable within sexes. Truncal skinfold sites (r 0.54 ± 0.70) emerged as the best ®eld indicators of intra-abdominal fat deposition. CONCLUSIONS: Patterns of intra-abdominal and subcutaneous fat distribution are identi®able in pubescent children using magnetic resonance imaging. An acceptable indication is provided by truncal skinfolds.

. (2012) 'Discrepancies in accelerometer-measured physical activity in children due to cut-point non-equivalence and placement site.', Journal of sports sciences., 30 (12). pp. 1303-1310. Further information on publisher's website:http://dx.doi.org/10. 1080/02640414.2012.709266 Publisher's copyright statement:This is an electronic version of an article published in [include the complete citation information for the nal version of the article as published in the print edition of the journal]. Journal of sports sciences is available online at: http://www.tandfonline.com/openurl?genre=articleissn=0264-0414volume=30issue=12spage=1303Additional information: Use policyThe full-text may be used and/or reproduced, and given to third parties in any format or medium, without prior permission or charge, for personal research or study, educational, or not-for-prot purposes provided that:• a full bibliographic reference is made to the original source • a link is made to the metadata record in DRO • the full-text is not changed in any way The full-text must not be sold in any format or medium without the formal permission of the copyright holders.Please consult the full DRO policy for further details. Running title: Accelerometer cut-points and placement site AbstractThis study examined dissonance in physical activity (PA) between two youth-specific hipderived cut-points for the Actiwatch (AW), and compared PA between hip and wrist placements using site-specific cut-points. Twenty-four children aged 11.2 ± 0.5 years wore AW on the right hip and non-dominant wrist during a typical school day. Minutes of sedentary behaviour (SB) and vigorous activity (VPA) were greater using Puyau et al. (2002) cut-points, but light (LPA), moderate (MPA), and moderate-to vigorous (MVPA) were lower when derived using Puyau et al. (2004) cut-points (p<0.01). Total hip activity counts were lower than wrist. Minutes of SB were greater at the hip. Minutes of LPA, VPA and MVPA were lower at the hip (p<0.01). MPA was greater at the hip, but differed only when applying the Puyau et al. 2004 cut-points (p<0.01). In conclusion, data comparisons between two hip derived AW cut-points and between hip and wrist data are inappropriate. Future researchers using the AW at the hip should present data reduced using both published cut-points. As hip and wrist data differ, the wrist placement is preferable as it will likely increase children's compliance to monitoring protocols due to reduced obtrusiveness compared to the hip.

A number of theoretical models have been proposed in recent years to explain pacing strategies observed in individual competitive endurance events. These have typically related to the internal regulatory processes that inform the making of decisions relating to muscular work rate. Despite a substantial body of research which has investigated the influence of collective group dynamics on individual behaviors in various animal species, this issue has not been comprehensively studied in individual athletic events. This is somewhat surprising given that athletes often directly compete in close proximity to one another, and that collective behavior has also been observed in other human environments including pedestrian interactions and financial market trading. Whilst the reasons for adopting collective behavior are not fully understood, collective behavior is thought to result from individual agents following simple local rules that result in seemingly complex large systems that act to confer some biological advantage to the collective as a whole. Although such collective behaviors may generally be beneficial, competitive endurance events are complicated by the fact that increasing levels of physiological disruption as activity progresses may compromise the ability of some individuals to continue to interact with other group members. This could result in early fatigue and relative underperformance due to suboptimal utilization of physiological resources by some athletes. Alternatively, engagement with a collective behavior may benefit all due to a reduction in the complexity of decisions to be made and a subsequent reduction in cognitive loading and mental fatigue. This paper seeks evidence for collective behavior in previously published analyses of pacing behavior and proposes mechanisms through which it could potentially be either beneficial, or detrimental to individual performance. It concludes with suggestions for future research to enhance understanding of this phenomenon.

Abstract:Background:The assessment of standing turning performance is proposed to predict fall risk in older adults. This study investigated differences in segmental coordination during a 360° standing turn task between older community-dwelling fallers and non-fallers. Methods:Thirty-five older adults age mean (SD) of 71 (5.4) years performed 360° standing turns.Head, trunk and pelvis position relative to the laboratory and each other were recorded using a Vicon motion analysis system. Fall incidence was monitored by monthly questionnaire over the following 12 months and used to identify non-faller, single faller and multiple faller groups. Results:Multiple fallers were found to have significantly different values, when compared to nonfallers, for pelvis onset (p=0.002); mean angular separation in the transverse plane between the head and trunk (p=0.018); peak angular separation in the transverse plane between the trunk and pelvis (p=0.013); and mean angular separation between the trunk and pelvis (p<0.001). Conclusions:Older adults who subsequently experience multiple falls show a simplified turning pattern to assist in balance control. This may be a predictor for those at increased risk of falling.