Comparison of accelerometer and pedometer measures of physical activity in boys and girls, ages 8-10 years

Accelerometers record total physical activity and time spent at different intensities. Pedometers indicate total activity only. The aim of this study was to assess the relationship between pedometer counts and attainment of > or = 60 min of moderate activity. Thirty-four children, ages 8-10 years, wore a Tritrac accelerometer and Yamax pedometer. Published recommendations of steps per day were compared to attainment of > or = 60 min moderate activity. Boys who accumulated 13,000 steps.d(-1) and girls who accumulated 12,000 steps.d(-1) engaged in > or = 60 min moderate activity. However, 23% of boys and 15% of girls did not reach the pedometer thresholds but did engage in > or = 60 min moderate activity. In conclusion, these pedometer thresholds provide a reasonable estimation when assessment of physical activity intensity is not possible.     

Gender differences in throwing form of children ages 6-8 years during a throwing game

The study purposes were to describe throwing form and gender differences before and after instruction during a game. Children's (ages 6-8, n = 105) throwing form was assessed while they played a game (snowball) using the Body Component Assessment for Throwing in Games to determine the modal developmental levels for the step, trunk, and forearm components. Each student received four 30-min sessions of throwing instruction. There were significant (p < .017) gender differences at each session and for each component. A Wilcoxon-Signed Ranks Test revealed differences (p < .017) between pretest and after instruction for boys' trunk and forearm components and girls'step and trunk components. The improvement after instruction and gender differences were similar to those found in a controlled, practice context.     

Blood lactate response and critical speed in swimmers aged 10-12 years of different standards

It has previously been shown that measurement of the critical speed is a non-invasive method of estimating the blood lactate response during exercise. However, its validity in children has yet to be demonstrated. The aims of this study were: (1) to verify if the critical speed determined in accordance with the protocol of Wakayoshi et al. is a non-invasive means of estimating the swimming speed equivalent to a blood lactate concentration of 4 mmol x l(-1) in children aged 10-12 years; and (2) to establish whether standard of performance has an effect on its determination. Sixteen swimmers were divided into two groups: beginners and trained. They initially completed a protocol for determination of speed equivalent to a blood lactate concentration of 4 mmol x l(-1). Later, during training sessions, maximum efforts were swum over distances of 50, 100 and 200 m for the calculation of the critical speed. The speeds equivalent to a blood lactate concentration of 4 mmol x l(-1) (beginners = 0.82 +/- 0.09 m x s(-1), trained = 1.19 +/- 0.11 m x s(-1); mean +/- s) were significantly faster than the critical speeds (beginners = 0.78 +/- 0.25 m x s(-1), trained = 1.08 +/- 0.04 m x s(-1)) in both groups. There was a high correlation between speed at a blood lactate concentration of 4 mmol x l(-1) and the critical speed for the beginners (r= 0.96, P < 0.001), but not for the trained group (r= 0.60, P> 0.05). The blood lactate concentration corresponding to the critical speed was 2.7 +/- 1.1 and 3.1 +/- 0.4 mmol x l(-1) for the beginners and trained group respectively. The percent difference between speed at a blood lactate concentration of 4 mmol x l(-1) and the critical speed was not significantly different between the two groups. At all distances studied, swimming performance was significantly faster in the trained group. Our results suggest that the critical speed underestimates swimming intensity corresponding to a blood lactate concentration of 4 mmol x l(-1) in children aged 10-12 years and that standard of performance does not affect the determination of the critical speed.     

Construct validity of the resistance training skills battery in children aged 7-10 years

The current study sought to examine the construct validity of the Resistance Training Skills Battery for Children (RTSBc), a movement screen purported to assess resistance training skill in children. Children aged 7–10 years (n = 27, 21 males, 6 females) undertook measures of resistance training skill via the RTSBc, motor competence and muscular fitness. Using a median split for RTSBc scores, children were categorised as high or low resistance training competence. Univariate ANCOVAs, controlling for maturation, were used to examine whether measures of muscular fitness and motor competence scores differed as a function of RTSBc competence. Children who were classified as high for resistance training competence had significantly better motor competence (P = .001) and significantly faster 10 m sprint speed (P = .001). However, medicine ball throw and standing long jump scores as well as peak and average isokinetic muscle strength did not differ as a function of RTSBc (P > 0.05). In all cases maturation was significant as a covariate. This study is the first to demonstrate construct validity of the RTSBc as a measure of general motor competence and sprint speed, but not strength, in children aged 7–10 years.     

How physically literate are children today? A baseline assessment of Greek children 8-12 years of age

ABSTRACT

Developing Physical Literacy (PL) in children is considered a promising concept for establishing active lifestyle habits; yet research evidence is scarce. This study aimed at comprehensively assessing PL in 8-12-year-old Greek children. For that purpose, the Canadian Assessment of Physical Literacy (CAPL-2) was administered to 715 children (M age = 10.2, SD = 1.3 years). Analyses of variance were applied on participants’ total, domain and individual measures scores, examining potential gender and age differences; whereas, participants’ classification and proportion across CAPL-2 interpretive categories were computed. Results revealed that there were no practically important differences (η² < .14) between boys and girls or younger (grades 3 & 4) and older children (grades 5 & 6). Greek children presented insufficient levels of PL (their total score classified them into “progressing” PL level). CAPL-2 domains and individual measures scores showed that participants were highly motivated and felt confident to participate in physical activity (PA); however, they exhibited low PA as well as unsatisfactory physical competence, knowledge, and understanding to value and take responsibility for engagement in PA. Although further research is needed for a comprehensive picture of PL correlates, our findings highlight the need for providing Greek children with ample opportunities to enhance their PL.     

基于儿童足部发育规律及步态特征的6～10岁童鞋设计原则

结合华南师范大学附小20名女童静、动态足底压力测试数据、穿鞋习惯、消费观念等,从生物力学角度对儿童出现的主要足部不适症状进行分析,指出中国6～10岁童鞋设计应遵循的主要原则:一是与脚的形状相似,成扇形,为足的自然生长发育创造条件;二是儿童走路时鞋子产生弯折的部位符合儿童足的比例,不应只是成人鞋的翻版;三是通过增加足中部及足后跟稳定性的方法达到减小足底压力的目的。并建议小童、中童、大童鞋的划分标准以年龄为依据,而不应以鞋码大小为依据。     

Changes in short-term power output in 10- to 12-year-olds

In this study, we used multi-level regression modelling to assess the influence of age, sex, body size, skinfold thicknesses, maturity, thigh muscle volume and isokinetic leg strength on the development of load- and inertia-adjusted peak (1 s) and mean power (30 s) determined using the Wingate anaerobic test. Fifteen males and 19 females were measured twice, first aged 10.0 +/- 0.3 years and then aged 11.8 +/- 0.3 years. Initial models identified body mass and height as significant explanatory variables (P < 0.05) for peak power and mean power, with an additional age effect for the former. No significant differences between the sexes or maturity effects were observed for either peak or mean power (P > 0.05). The introduction of sum of skinfolds improved the fit of the model and rendered the height term non-significant for both peak and mean power (P> 0.05). An age effect became apparent for mean power. When isokinetic leg strength and thigh muscle volume were entered into the model, the latter exerted a significant effect on both peak and mean power (P< 0.05), whereas isokinetic leg strength was not a significant explanatory variable for either (P> 0.05). In conclusion, thigh muscle volume exerts a positive influence on young people's short-term power output, which is additional to the effects of body mass, sum of skinfolds and age.     

Psychometric properties of the Brunel Mood Scale in Chinese adolescents and adults

Abstract

Building on the work of Terry and colleagues (Terry, P. C., Lane, A. M., Lane, H. J., & Keohane, L. (1999). Development and validation of a mood measure for adolescents. Journal of Sports Sciences, 17, 861–872; Terry, P. C., Lane, A. M., & Fogarty, G. J. (2003). Construct validity of the Profile of Mood States-Adolescents for use with adults. Psychology of Sport & Exercise, 4, 125–139.), the present study examined the validity and internal consistency reliability of the Chinese version of the Brunel Mood Scale (BRUMS-C) among 2,548 participants, comprising adolescent athletes (n = 520), adult athletes (n = 434), adolescent students (n = 673), and adult students (n = 921). Both adolescent and adult athletes completed the BRUMS-C before, during, or after regular training and both adolescent and adult students completed the BRUMS-C in a classroom setting. Confirmatory factor analyses (CFAs) provided support for the factorial validity of a 23-item six-factor model, with one item removed from the hypothesised measurement model. Internal consistency reliabilities were satisfactory for all subscales across each of the four samples. Criterion validity was supported with strong relationships between the BRUMS-C, abbreviated POMS, and Chinese Affect Scale consistent with theoretical predictions. Multi-sample CFAs showed the BRUMS-C to be invariant at the configural, metric, strong, and structural levels for all samples. Furthermore, latent mean difference analyses showed that athletes reported significantly higher levels of fatigue than students while maintaining almost the same levels of vigour, and adolescent students reported significantly higher levels of depressed mood than the other three samples.     

Kinematic analysis of the standing long jump in children 6- to 12-years-old

The purpose of this study was to analyze the kinematic variables that determine the performance of the standing long jump in children 6- to 12-years-old. There were 121 healthy children (58 girls) recorded while they performed the standing long jump test. All kinematic variables showed a significant correlation with calculated jump distance and measured jump distance, except for the knee joint angle at maximum shoulder extension angle, ankle joint angle at maximum shoulder extension angle, and shoulder joint angle at maximum knee flexion angle. Stepwise multiple regression analysis showed that sex, age, and body mass index accounted for 51.1% of the jump distance variance. Among all the kinematic variables, take-off distance and take-off speed were accounted for the most of the variation in the jump distance. Physical education teachers and coaches should consider special attention to these anthropometrics and kinematic aspects in improving the standing long jump performance in children.     

Segmented sedentary time and physical activity patterns throughout the week from wrist-worn ActiGraph GT3X+ accelerometers among children 7-12 years old

Background:This study examined the volume and patterns of physical activity(PA) and sedentary time(ST) across different segments of the week among boys and girls.Methods:A total of 188 children aged 7-12 years wore a wrist-mounted ActiGraph GT3 X+accelerometer for 7 days.Time spent in PA and ST was calculated using ActiLife software.The mean number of minutes of light PA,moderate PA,vigorous PA,moderate-to-vigorous PA(MVPA),and ST were calculated per weekday(before school,during school,and after school) and per weekend day(morning and afternoon-evening).Results:After school represented the greatest accumulation of ST compared with before school and during school segments.Boys engaged in225.4 min/day of ST(95% confidence interval(CI):216-235),and girls engaged in 222.2 min/day of ST(95%CI:213-231).During school,boys engaged in significantly more MVPA than girls(46.1 min/day(95%CI:44-48) vs.40.7 min/day(95%CI:39-43)).Across the whole weekday,boys participated in significantly more MVPA than girls(103.9 min/day(95%CI:99-109) vs.95.7 min/day(95%CI:90-101)).The weekend afternoon—evening segment represented the larger accumulation of ST,where boys were significantly more sedentary than girls(367.5 min/day(95%CI:353-382) vs.339.8 min/day(95%CI:325-355),respectively).Conclusion:Our findings suggest that children are highly sedentary and spend little of their time in school in MVPA,especially girls.Routine breaks in school elicit increases in light PA and MVPA.Future work should consider the use of more active breaks within school time to encourage PA and reduce ST.     

Validity of an Athletic Skills Track among 6- to 12-year-old children

The purpose of this study was to examine the feasibility and validity of an Athletic Skills Track (AST) to assess fundamental movement skills among 6- to 12-year-old children in a physical education setting. Four hundred sixty-three Dutch children (211 girls, 252 boys) completed three tests: the Körperkoordinationstest für Kinder (KTK) and two Athletic Skills Tracks (AST-1, AST-2). The validity of AST-1 and AST-2 was examined by correlating the time (s) needed to complete the tracks and the KTK Motor Quotient (MQ).

Overall, there was a low correlation between AST-1 and the KTK MQ (r = –0.474 (P < 0.01)) and a moderate correlation between AST-2 and the KTK MQ (r = –0.502 (P < 0.01)). When split up by age group the associations were much higher and ranged between r = –0.469 and r = –0.767), with the exception of the low correlation coefficient of the AST-2 in 7-year-olds. The results indicate that fundamental movement skills of 6- to 12-year-old children can be assessed with a quick, convenient and low-cost motor competence test in a physical education setting, i.e., an Athletic Skills Track. Future studies should further assess the reliability, discriminative ability and validity of age-specific versions of the AST.     

Psychometric properties of the motor diagnostics in the German football talent identification and development programme

The utilisation of motor performance tests for talent identification in youth sports is discussed intensively in talent research. This article examines the reliability, differential stability and validity of the motor diagnostics conducted nationwide by the German football talent identification and development programme and provides reference values for a standardised interpretation of the diagnostics results. Highly selected players (the top 4% of their age groups, U12–U15) took part in the diagnostics at 17 measurement points between spring 2004 and spring 2012 (N = 68,158). The heterogeneous test battery measured speed abilities and football-specific technical skills (sprint, agility, dribbling, ball control, shooting, juggling). For all measurement points, the overall score and the speed tests showed high internal consistency, high test–retest reliability and satisfying differential stability. The diagnostics demonstrated satisfying factorial-related validity with plausible and stable loadings on the two empirical factors “speed” and “technical skills”. The score, and the technical skills dribbling and juggling, differentiated the most among players of different performance levels and thus showed the highest criterion-related validity. Satisfactory psychometric properties for the diagnostics are an important prerequisite for a scientifically sound rating of players’ actual motor performance and for the future examination of the prognostic validity for success in adulthood.     

Evaluation of the exercise workload of broadcast calisthenics for children and adolescents aged 11-17 years

The aim of this study was to examine the exercise workload of the 3rd Series of National Broadcast Calisthenics for Elementary and Middle School Students. Altogether, 120 students aged 11-17 years were randomly selected from elementary and middle schools to participate in the study. Each participant performed a cycle ergometer test to obtain maximum oxygen uptake ([Vdot]O(2max)) and maximum heart rate values. In the laboratory, oxygen uptake ([Vdot]O(2)), metabolic equivalents (METs), and heart rate were recorded continuously throughout a calisthenics session performed by the participants. Ratings of perceived exertion (RPE) were also recorded. Throughout the calisthenics session, mean percentage of [Vdot]O(2) reserve varied from 30.7% to 41.2%, mean percentage of heart rate reserve from 39.0% to 56.9%, and mean RPE from 9.0 to 10.4. The mean energy cost during most of the segments across the four routines of calisthenics was significantly higher (P?相似文献   

Evaluation of low-cost, objective instruments for assessing physical activity in 10-11-year-old children

This study compared step counts detected by four, low-cost, objective, physical-activity-assessment instruments and evaluated their ability to detect moderate-to-vigorous physical activity (MVPA) compared to the ActiGraph accelerometer (AG). Thirty-six 10-11-year-old children wore the NL-1000, Yamax Digiwalker SW 200, Omron HJ-151, and Walk4Life MVP concurrently with the AG during school hours on a single day. AG MVPA was derived from activity count data using previously validated cut points. Two of the evaluated instruments provided similar group mean MVPA and step counts compared to AG (dependent on cut point). Low-cost instruments may be useful for measurement of both MVPA and steps in children's physical activity interventions and program evaluation.     

游泳运动员少年儿童(10-12岁)阶段力量素质的训练特点

力量素质是游泳运动员的专项素质。在少年儿童训练阶段,务必有计划,有目的的选择有效的训练手段并和其它素质发展有机的结合起来去合理安排,以使身体素质整体水平得到均衡发展,从而达到运动成绩逐年提高,为培养高水平游泳运动员打下坚实的基础。     

10-11岁肥胖儿童主要运动减肥手段能量代谢率的研究

目的:通过对单纯性肥胖儿童几种主要运动手段能量代谢率进行研究,了解肥胖儿童主要运动手段的能量消耗率,为儿童运动减肥提供科学依据.方法:按身高标准体重选出30名10-11岁肥胖儿童,用便携式能量代谢仪测定其主要手段的能量代谢率.结果:10～11岁肥胖儿童安静能量代谢率为(1.15±0.29) kcal/m2· min,慢跑为(5.38±0.72)kcal/m2· min,爬行为(6.12±0.874)kcal/m2·min,30b/min斜卧撑为(2.96±0.22)kcal/m2· min,60b/min跳绳为(3.28±0.31) kcal/m2· min,60b/min高抬腿为(2.78±0.35)kcal/m2· min.结论:各项运动手段的该能量代谢率可以为肥胖儿童运动减肥提供科学依据.     

Accelerometer Bluetooth proximity validation in parents and early years children

The purpose of this study was to examine the validity of a novel technique determining parent–child proximity using Bluetooth-enabled accelerometers. Nineteen parents and children (18–60 months; 38.4 ± 13.2 months) wore an ActiGraph wGT3X-BT accelerometer for 7 days. Parental accelerometers continuously emitted a Bluetooth signal, while children’s accelerometers recorded signal detection once per minute. Parents reported whether they were “AWAY”/“WITH” their child using time-use diaries in 5-minute intervals for 2 days. Presence (1) or absence (0) of a Bluetooth signal was averaged over the 5-minute time frame. Accelerometer and time-use diary variables produced 8,331 comparative observations. Area under the curve (AUC) via receiver operator characteristic (ROC) curve was 0.84 (95% confidence intervals: 0.84, 0.85), and the optimal cut-point was 0.0. Specifically, sensitivity (0.82) and specificity (0.81) were maximized when classifying all positive proximity tags (0.20–1.00) as “WITH” and all negative proximity tags (0.0) as “AWAY”. Accelerometer-derived parent–child proximity demonstrated good concurrent validity.     

Reliability and concurrent validity of a motor skill competence test among 4- to 12-year old children

The purpose of this study was to examine the test-retest reliability, internal consistency and concurrent validity of the Athletic Skills Track (AST). During a regular PE lesson, 930 4- to 12-year old children (448 girls, 482 boys) completed two motor skill competence tests: (1) the Körperkoordination-Test für Kinder (KTK) and (2) an age-related version of the AST (age 4–6 years: AST-1, age 6–9 years: AST-2, and age 9–12 years: AST-3). The test-retest reliability of the AST was high (AST-1: ICC = 0.881 (95% CI: 0.780–0.934); AST-2: ICC = 0.802 (95% CI: 0.717–0.858); and AST-3: ICC = 0.800 (95% CI: 0.669–0.871). The internal consistency, concerning the three age-bands of the AST was above the acceptable level of Cronbach’s α > 0.70 (AST-1: α = 0.764; AST-2: α = 0.700; and AST-3: α = 0.763). There was a moderate to high correlation between the time to complete the AST, and the age- and gender-related motor quotients of the KTK (AST-1: r = ?0.747, p = 0.01; AST-2: r = ?0.646, p = 0.01; and AST-3: r = ?0.602, p = 0.01). The Athletic Skills Track is a reliable and valid assessment tool to assess motor skill competence among 4- to 12-year old children in the PE setting.     

Differences in physical fitness and gross motor coordination in boys aged 6-12 years specializing in one versus sampling more than one sport

The Developmental Model of Sports Participation proposes two pathways towards expertise in sports between 6 and 12 years of age: early specialization and early diversification. This study investigated the effect of sampling various sports and of spending many or few hours in sports on fitness and gross motor coordination. Altogether, 735 boys in three age groups (6-8, 8-10, and 10-12 years) were profiled using a fitness test battery. A computerized physical activity questionnaire was used to obtain data on sports participation. In the eldest group, (M)ANCOVA showed a positive effect of sampling various sports on strength, speed, endurance, and gross motor coordination (P < 0.05). A positive effect of many hours per week spent in sports was apparent in every age group. These data suggest an acute positive effect of many hours in sports and a latent positive effect of early sampling on fitness and gross motor coordination. Multiple comparisons revealed that boys aged 10-12 years, who spent many hours in various sports, performed better on standing broad jump (P < 0.05) and gross motor coordination (P < 0.05) than boys specializing in a single sport. Therefore, our results highlight the importance of spending many hours in sports and sampling various sports in the development of fitness and gross motor coordination.     

近10年体育教学方法的变革与发展

为了促进新体育课程改革深入发展,采用文献资料法、实践经验总结法和专家访谈法,从体育教学方法的角度,运用专家、学者和一线教师们的观点和案例,对我国新一轮基础教育体育课程十年改革的情况进行回顾和总结.结果表明,十年来,我国的体育教学方法发生了前所未有的积极变化.