Mediating effects of resistance training skill competency on health-related fitness and physical activity: the ATLAS cluster randomised controlled trial

The purpose of this study was to examine the mediating effect of resistance training skill competency on percentage of body fat, muscular fitness and physical activity among a sample of adolescent boys participating in a school-based obesity prevention intervention. Participants were 361 adolescent boys taking part in the Active Teen Leaders Avoiding Screen-time (ATLAS) cluster randomised controlled trial: a school-based program targeting the health behaviours of economically disadvantaged adolescent males considered “at-risk” of obesity. Body fat percentage (bioelectrical impedance), muscular fitness (hand grip dynamometry and push-ups), physical activity (accelerometry) and resistance training skill competency were assessed at baseline and post-intervention (i.e., 8 months). Three separate multi-level mediation models were analysed to investigate the potential mediating effects of resistance training skill competency on each of the study outcomes using a product-of-coefficients test. Analyses followed the intention-to-treat principle. The intervention had a significant impact on the resistance training skill competency of the boys, and improvements in skill competency significantly mediated the effect of the intervention on percentage of body fat and the combined muscular fitness score. No significant mediated effects were found for physical activity. Improving resistance training skill competency may be an effective strategy for achieving improvements in body composition and muscular fitness in adolescent boys.     

三明市高校高级知识分子超重肥胖现象探析

采用测试法、询问法和数理统计法,对三明市高校高级知识分子身体质量指数及相关影响因素进行研究．结果表明：高级知识分子超重、肥胖的现象已较为严重,而且在超重、肥胖的趋势上男性要大于女性．超重肥胖现象主要与高级知识分子日常的饮食习惯和体育锻炼不足有关,也与工作性质有一定的关系．     

Frequent sit-to-stand transitions and several short standing periods measured by hip-worn accelerometer are associated with smaller waist circumference among adults

This cross-sectional study analysed the association of sedentary behaviour (SB) and standing with waist circumference. Finnish adults aged 30-75 years from a sub-sample of population-based Health 2011 Study used a hip-worn tri-axial accelerometer (Hookie AM20, Traxmeet, Ltd, Espoo, Finland) for seven days. Those 1405 participants (57% women) who used accelerometer at least four days, minimum of 10 hours/day, were included. SB and standing were analysed in 6s epochs using validated algorithm. Daily total time, daily number and accumulated time from bouts (30s–5min,30s–10min,30s–15min,30s 30min,>5min,>10min,>15min, >30min) as well as daily number of sit-to-stand transitions were determined. Waist circumference (cm) was measured in standardized way. Participants’ mean age was 52 years (SD 12.2). Mean waist circumference was 97cm (SD 12.3) in men and 87cm (SD 12.7) in women. According to multivariable stepwise linear regression analysis, sit-to-stand transitions [standardised regression coefficient (β)= -0.14, 95%CI -0.20 to -0.09], standing bouts of 30s–5min (β= -0.21, 95%CI -0.26 to -0.15) and number of 30s-30min SB bouts (β=0.12, 95%CI 0.06 to 0.17) were most strongly associated with waist circumference. Besides assessing total SB time, future studies should assess also different bout lengths of SB and sit-to-stand transitions and standing times should be assessed separately.     

The Relationship Between Motor Skill Proficiency and Body Mass Index in Preschool Children

Abstract

The purpose of this study was to examine the relationship between motor proficiency and body mass index (BMI) in preschool children. Thirty-eight children ages 4–6 years had their BMI calculated and were assessed using the Movement Assessment Battery for Children-2 (MABC-2; Henderson, Sugden, & Barnett, 2007). These data were analyzed in two ways. The correlation between BMI and MABC-2 percentile ranks was calculated. Next, the groups were subdivided based on BMI status (high, M = 85.5; medium, M = 49.8; low, M = 10.8), and compared using t tests to determine if differences existed in MABC-2 percentile ranks. No significant relationship existed between MABC-2 and BMI percentile ranks (r = -.237). However, significant differences in MABC-2 percentile ranks existed between high and low (p = .042), and high and medium (p = .043) groups. These results suggest that preschool children classified as overweight or obese may have lower motor proficiency than their normal weight and under weight peers. This study indicates there is a direct relationship between motor proficiency and BMI in the preschool population.     

体质指数法、皮褶厚度法和生物电阻抗法判断青少年超重、肥胖的一致性

运用体质指数法、皮褶厚度法及生物电阻抗法,判断上海城区儿童青少年超重、肥胖发生率及其一致性。结果显示:3种方法在判断不同年龄、性别儿童青少年超重、肥胖上一致性较低;测量原理与精确性不同,青少年儿童体成分化学组成不成熟及诊断、筛查标准的差异可能是3种方法一致性较低的原因。提出应建立适合我国儿童青少年"多维模型"假设下的体脂率预测方程。     

湖南省高校肥胖大学生体育态度的调查研究

为促进超重和肥胖大学生积极参与体育锻炼,有效提高大学体育教学质量,以文献资料、问卷调查法对湖南省高校390名肥胖大学生的身体发育状况和体育态度、体育行为现状进行调查分析。结果表明：被调查的肥胖大学生体育态度基本处于低水平,极少甚至不参加课余体育锻炼。提出在体育教学设计中应区别对待超重和肥胖大学生,有针对性的提高其体育态度的认知成分水平。     

High Body Mass Index is not a barrier to physical activity: Analysis of international rugby players’ anthropometric data

Abstract

Recent data indicate that levels of overweight and obesity are increasing at an alarming rate throughout the world. At a population level (and commonly to assess individual health risk), the prevalence of overweight and obesity is calculated using cut-offs of the Body Mass Index (BMI) derived from height and weight. Similarly, the BMI is also used to classify individuals and to provide a notional indication of potential health risk.

It is likely that epidemiologic surveys that are reliant on BMI as a measure of adiposity will overestimate the number of individuals in the overweight (and slightly obese) categories. This tendency to misclassify individuals may be more pronounced in athletic populations or groups in which the proportion of more active individuals is higher. This differential is most pronounced in sports where it is advantageous to have a high BMI (but not necessarily high fatness). To illustrate this point we calculated the BMIs of international professional rugby players from the four teams involved in the semi-finals of the 2003 Rugby Union World Cup. According to the World Health Organisation (WHO) cut-offs for BMI, approximately 65% of the players were classified as overweight and approximately 25% as obese.

These findings demonstrate that a high BMI is commonplace (and a potentially desirable attribute for sport performance) in professional rugby players. An unanswered question is what proportion of the wider population, classified as overweight (or obese) according to the BMI, is misclassified according to both fatness and health risk? It is evident that being overweight should not be an obstacle to a physically active lifestyle. Similarly, a reliance on BMI alone may misclassify a number of individuals who might otherwise have been automatically considered fat and/or unfit.     

福建省肥胖大学生课外体育活动的现状调研

通过对福建省十所普通高校的肥胖大学生课外体育活动的现状进行调查与分析，结果表明：肥胖大学生参加课外体育活动的主要动机是想减肥健身、提高身体素质和娱乐身心等，但实际课外体育活动的现状不尽如人意，被调查参加课外体育活动3次/周以上仅占13.3％，每次运动时间30min以上仅占68.3%，且所选择的活动项目比较单一，缺少一些针对性的内容，也缺乏适宜运动强度的知识，难以达到减肥的效果。肥胖自身存在的问题、缺少场地器材、学习紧张、余暇时间少、缺少理论知识与实践指导、缺少伙伴、缺乏组织管理等是造成肥胖大学生课外体育活动现状不佳的主要因素，结合现状提出改善肥胖大学生课外体育活动现状相应的对策。     

基于决策树模型的幼儿超重关键因素研究

目的:基于决策树模型探讨引起幼儿超重的关键因素。方法:招募南昌市23所幼儿园5870名3~6岁幼儿,测量身高、体重;问卷调查幼儿身体活动、静坐行为、出生信息,父母的育儿方式、身体形态、锻炼行为和家庭情况,并将其划分为36个变量;采用IBM SPSS modeler软件创建CHAID决策树模型,筛选幼儿超重的关键性因素。结果:CHAID模型准确率达85.23%。CHAID模型结果显示,8个变量与幼儿超重有较强关联性,各变量按重要性排序依次为室外身体活动时间、父亲BMI、母亲BMI、父亲收入、室内身体活动时间、父亲受教育程度、喂养方式、看电视时间。结论:身体活动尤其是室外身体活动与幼儿超重的关系最为密切,父母肥胖程度、父亲收入与受教育情况、喂养方式、静坐行为也是导致幼儿超重的关键性因素。     

河北省青少年超重与肥胖人群膳食特点研究

采用问卷调查法和文献资料法,对河北省石家庄、沧州、承德、张家口四个地区的385名超重与肥胖中学生和219名正常体重中学生进行了调查研究,旨在分析总结出超重与肥胖青少年的膳食特点,探讨导致肥胖的饮食因素,为其控体重、减体重提供科学的理论依据。