Familial aggregation in physical activity.

The purposes of this study were to (a) examine the stability and consistency of the Caltrac accelerometer (Hemokinetics, Madison, WI) and an activity record to assess physical activity in children and adults (Experiment 1), and (b) to determine if there is a relationship between parents and their children in physical activity level (Experiment 2). Thirty 5-9-year-old children and their biological parents wore Caltrac accelerometers for three consecutive days (including one weekend day). At the same time, parents completed a Caltrac Activity Record (CAL REC) for themselves and their child. Dependent variables were counts per day for the Caltrac and minutes of light activity and activity for the CAL REC. Between-day correlations for the Caltrac ranged from r = .73 to .87 for the parents (p less than .001) and from r = .38 (p less than .04) to .79 (p less than .001) for the children. An analysis of variance with repeated measures indicated no significant differences for the Caltrac between days for parents and children. Between-day correlations for CAL REC ranged from r = .67 to .91 (p less than .05) for parents and r = .36 to .72 (p less than .05) for children, and there were no significant differences between days. In Experiment 2, chi 2 analyses were used to examine familial resemblance in physical activity. Using the Caltrac, familial resemblance occurred in 67% (father and child) and 73% (mother and child) of the families. Using the CAL REC, familial aggregation was present in 70% (father and child) and 66% (mother and child) of the families.(ABSTRACT TRUNCATED AT 250 WORDS)     

Estimation of aerobic fitness from PACER performance with and without body mass index

Purpose: To develop models to estimate aerobic fitness (VO₂max) from PACER performance in 10- to 18-year-old youth, with and without body mass index (BMI) as a predictor. Method: Youth (N = 280) completed the PACER and a maximal treadmill test to assess VO₂max. Validation and cross-validation groups were randomly formed to develop and examine accuracy of models. Participants were classified into FitnessGram® Healthy Fitness Zone categories based on measured and estimated VO₂max and criterion-referenced validity was evaluated. Results: Multiple correlations between measured and estimated VO₂max ranged from .70 to .73, with standard errors of estimate between 6.43 and 6.68 mL·kg^?1·min^?1. Accuracy with and without BMI was nearly identical. Overall, criterion-referenced validity evidence was moderate. Conclusion: Moderately accurate and feasible models were developed. Minimal improvement in accuracy was noted when BMI was added as a predictor. The model with PACER and age as predictors has a high level of utility for youth fitness testing.     

The influence of maturation,body size and physical self-perceptions on longitudinal changes in physical activity in adolescent girls

Abstract

The aim of this study was to adopt a longitudinal design to explore the direct effects of both absolute and relative maturation and changes in body size on physical activity, and explore if, and how, physical self-perceptions might mediate this effect. We recruited 208 girls (11.8 ± 0.4 years) at baseline. Data were collected at three subsequent time points, each 6 months apart. At 18 months, 119 girls remained in the study. At each time point, girls completed the Physical Activity Questionnaire for Children, the Pubertal Development Scale (from which, both a measure of relative and absolute maturation were defined) and the Physical Self-Perception Profile, and had physical size characteristics assessed. Multilevel modelling for physical activity indicated a significant negative effect of age, positive effect for physical condition and sport competence and positive association for relatively early maturers. Absolute maturation, body mass, waist circumference and sum of skinfolds did not significantly contribute to the model. Contrary to common hypotheses, relatively more mature girls may, in fact, be more active than their less mature peers. However, neither changes in absolute maturation nor physical size appear to directly influence changes in physical activity in adolescent girls.     

Age, physical activity, physical fitness, body composition, and incidence of orthopedic problems

The incidence of orthopedic problems was examined in 5,582 men and women who attended the Cooper Clinic in Dallas, Texas between 1974 and 1982. The effects of age, physical activity, physical fitness, and body mass index (BMI) on the occurrence of these problems were examined using a proportional hazards approach. The expected risk of orthopedic problems per person-year was 0.045 for men and 0.046 for women. For men, physical fitness, BMI, and physical activity were associated with orthopedic problems, while for women, physical activity was the main predictor. Age was not a factor for either gender. The effect of change in physical fitness, physical activity, and BMI was examined in a subset of 2,325 persons with more than one visit to the clinic. For women, physical activity and a decrease in BMI were associated with orthopedic problems, while for men none of those factors were significant. Again, age was not a factor in either group. The absence of any age effect on the occurrence of problems suggests that with regard to orthopedic problems, moderate amounts of physical activity in generally healthy persons may be recommended without special consideration as to age.     

Progressive aerobic cardiovascular endurance run and body mass index among an ethnically diverse sample of 10-15-year-olds

This study examined the cardiovascular fitness (CVF, Progressive Aerobic Cardiovascular Endurance Run [PACER], number of laps completed) and the prevalence of at risk of overweight (AR) and overweight (OW) among 10-15-year-olds (48% girls)from the following ethnic backgrounds: African American (n = 2,604), Asian-Pacific Islander (n = 3,888), Hispanic (n = 11,680); and White non-Hispanic (n = 16,352). Hierarchal multiple linear regression analysis, controlling for height and weight, with White non-Hispanics serving as the comparison group, revealed a limited number of significant differences among PACER performances, with no values exceeding +/- 4.43 laps. Odds ratios (OR) for being classified as AR or OW were significantly greater (p < .01) in African American (OR = 1.25, 1.65) and Hispanic (OR = 2.33, 2.28) boys and girls, respectively, and Asian boys (OR = 1.43). The results of this cross-sectional analysis indicated negligible differences in CVF among ethnic groups, while AR and OW were consistent with previous reports for ethnic populations.     

Between-school variation in physical activity,aerobic fitness,and organized sports participation: A multi-level analysis

Abstract

A large proportion of a child's day is spent at school interacting with certain physical surroundings, teachers, and school friends. Thus, schools could have a marked impact on establishing physical activity habits. The aim of the present study was to assess between-school variation in physical activity, aerobic fitness, and organized sports participation. Altogether, we tested 1766 nine- and fifteen-year-old children attending 242 school classes at 35 different schools in Denmark in 1997–2003. The intra-class correlation coefficient (ICC) for objectively assessed physical activity ranged between 0.06 and 0.18 depending on the dimension of physical activity and the time considered (i.e. school time vs. leisure time). For aerobic fitness, an ICC of 0.10 was observed, whereas that for organized sports participation ranged between 0.01 and 0.10 depending on the age group. Studying between-school variation in physical activity provides information about the extent to which children adjust their physical activity habits according to the social and environmental circumstances that they share, and helps to plan future school-based physical activity studies, especially in terms of sample size and power calculation.     

有氧舞蹈对高校女大学生体质的影响

运用文献资料法、数理统计法和实验法,对60名女大学生进行16周的有氧舞蹈训练,研究有氧舞蹈对大学女生身体形态、素质、机能的影响。结果显示：实验后女生的体脂百分率和腰臀比存在显著性差异,体重变化不大;800m、立定跳远、1min仰卧起坐存在显著性差异,坐位体前屈无明显变化;肺活量和最大吸氧量指标显著提高,呼吸频率降低。结论：有氧舞蹈能促进女大学生体内多余脂肪的燃耗,减少体脂肪;发展腰腹部力量以及腿部力量;锻炼呼吸器官的功能,提高心肺的工作能力。     

健美操对中师女生身体形态与身体素质影响的初探

通过对我院50名参加健美锻炼的中师女生在训练前及训练后的身体成分、身体形态与身体素质状况的实验研究分析，探讨健美操运动在改善中师女生的形态与素质、促进生长发育、增进学生的身心健康等方面的重要作用。     

Changes in the stature,body mass and age of English professional rugby players: A 10-year review

Abstract

The aim of the study was to evaluate changes in the stature, body mass, age and number of players by playing position in the first team squads of English Premiership rugby union teams from 2002 to 2011. Medical personnel at each club reported the individual data for every first team squad player. The average annual number of players included in the study was 485.2 players per season (standard deviation: 58.0). The mean stature of players in all positions increased in the period 2002 to 2011 but statistically significant trends (P < 0.01) were only observed at fly half and prop. While the mean body mass of players increased in most positions only fly half and back row players showed statistically significant (P < 0.01) upward trends. Apart from second row forwards, the average age of players in all positions decreased but this trend was only significant (P < 0.01) at prop. The numbers of registered players in every position increased but these trends were only significant (P < 0.01) at prop. English Premiership professional rugby players are generally getting taller, heavier and younger but statistically significant changes were limited to fly halves (taller and heavier), props (taller and younger) and back row forwards (heavier).     

身高标准体重指标与大学生身体成分的关系

为探讨身高标准体重指标与身体成分的关系，以220名普通大学生（男女各110名）为实验对象，通过测量其身高、体重与身体成分，结果发现身高标准体重指标与身体成分之间相关性极低（P〉0．05），而体重指数（BMI）、体脂百分比和腰臀比（WHR）与身体成分有高度相关性（P〈0．01）。结论：（1）《大学生体质健康标准》中身高标准体重指标不能客观有效地评价身体成分；（2）建议在《大学生体质健康标准》中，评价身体成分的指标宜选体脂百分比、BMI和WHR，首选为体脂百分比。     

Objectively measured physical activity,body composition and physical fitness: Cross-sectional associations in 9- to 15-year-old children

The aim of this study was to examine and quantify the cross-sectional associations of body composition (BC), physical activity (PA) and sedentary time (ST) with physical fitness (PF) in children and adolescents. A sample of 594 Finnish students (56% girls), aged 9–15 (12.4?±?1.3 years) were selected for a study performed in 2013. The measurements of the Move! monitoring system for physical functional capacity were used to measure cardiorespiratory and musculoskeletal fitness and fundamental movement skills. Moderate-to-vigorous PA (MVPA) and ST were measured objectively with an accelerometer and BC by a bioelectrical impedance analysis. Fat mass index (FMI) and fat-free mass index (FFMI) were calculated to represent height-adjusted BC. Associations were explored with a linear regression model. In general, FMI had statistically significant negative associations, while FFMI and MVPA had positive associations with PF. No statistically significant associations were observed between ST and PF. In general, FMI had the strongest association with PF, although some variation occurred with sex and PF component. However, associations were practically relevant only in 20-m shuttle run, push-up, curl-up and 5-leaps test. For example, approximately 5?kg increase in fat mass in 155?cm tall children was estimated to correspond to 8 laps in 20-m shuttle run. Similar increase in fat-free mass corresponded to +4 and +6 laps, and 10?min increase in daily MVPA +3 and +2 laps in 20-m shuttle run, in boys and girls, respectively. Understanding these associations is necessary when interpreting children’s PF and designing interventions.     

Accelerometer-measured daily physical activity related to aerobic fitness in children and adolescents

Maximum oxygen uptake (VO(2PEAK)) is generally considered to be the best single marker for aerobic fitness. While a positive relationship between daily physical activity and aerobic fitness has been established in adults, the relationship appears less clear in children and adolescents. The purpose of this paper is to summarise recently published data on the relationship between daily physical activity, as measured by accelerometers, and VO(2PEAK) in children and adolescents. A PubMed search was performed on 29 October 2010 to identify relevant articles. Studies were considered relevant if they included measurement of daily physical activity by accelerometry and related to a VO(2PEAK) either measured directly at a maximal exercise test or estimated from maximal power output. A total of nine studies were identified, with a total number of 6116 children and adolescents investigated. Most studies reported a low-to-moderate relationship (r = 0.10-0.45) between objectively measured daily physical activity and VO(2PEAK). No conclusive evidence exists that physical activity of higher intensities are more closely related to VO(2PEAK), than lower intensities.     

Accelerometer-measured daily physical activity related to aerobic fitness in children and adolescents

Abstract

Maximum oxygen uptake ([Vdot]O_2PEAK) is generally considered to be the best single marker for aerobic fitness. While a positive relationship between daily physical activity and aerobic fitness has been established in adults, the relationship appears less clear in children and adolescents. The purpose of this paper is to summarise recently published data on the relationship between daily physical activity, as measured by accelerometers, and [Vdot]O_2PEAK in children and adolescents. A PubMed search was performed on 29 October 2010 to identify relevant articles. Studies were considered relevant if they included measurement of daily physical activity by accelerometry and related to a [Vdot]O_2PEAK either measured directly at a maximal exercise test or estimated from maximal power output. A total of nine studies were identified, with a total number of 6116 children and adolescents investigated. Most studies reported a low-to-moderate relationship (r = 0.10–0.45) between objectively measured daily physical activity and [Vdot]O_2PEAK. No conclusive evidence exists that physical activity of higher intensities are more closely related to [Vdot]O_2PEAK, than lower intensities.     

Effects of aerobic and cognitively-engaging physical activity on academic skills: A cluster randomized controlled trial

ABSTRACT

This cluster randomized controlled trial (trial-number #) compares effects of two school-based physical activity interventions (aerobic vs. cognitively-engaging) on reading, mathematics, and spelling achievement; and whether effects are influenced by volume of moderate-to-vigorous physical activity and baseline achievement. Twenty-two primary schools participated, where a third and fourth grade class were randomly assigned to the intervention or control group. Intervention groups were randomly assigned to a 14-week aerobic or cognitively-engaging intervention, receiving four physical education lessons a week. Control groups followed their regular physical education program. Academic achievement of 891 children (mean age 9.17 years, 49.4% boys) was assessed with standardized tests before and after the interventions. Post-Test academic achievement did not significantly differ between intervention groups and control group. A higher volume of moderate-to-vigorous physical activity resulted in better post-test mathematics achievement in both intervention groups, and post-test spelling achievement in the cognitively engaging intervention group. Compared to the control group, lower achievers in reading performed better in reading after the cognitively-engaging intervention. A combination of moderate-to-vigorous physical activity and cognitively-engaging exercises seems to have the most beneficial effects. Future intervention studies should take into account quantitative and qualitative aspects of physical activity, and children’s baseline academic achievement.     

Social inequalities in body weight and physical activity: exploring the role of fitness centers

Fitness centers are a viable option for physical activity, particularly in climates with significant weather variation. Due to variation in economic and social expressions ofexclusivity, fitness centers may have some relation to social inequalities in physical inactivity and related health outcomes; thus, our objective was to explore this relation. Using publicly available data and guided by Bourdieu's theory of habitus, we classified fitness centers in Calgary, Canada, on three dimensions of exclusivity (economic, social, and appearance). We found that, although some highly exclusive centers exist, most demonstrated low exclusivity based on our dimensions. An overall contribution of centers to inequalities appears to be limited; however, caution is warranted in light of cutbacks to municipal budgets that can have an impact on publicly funded facilities.     

Meeting guidelines for physical activity,muscle strength,and sleep lowers mortality risk:Commentary on: "Associations between aerobic and musclestrengthening physical activity,sleep duration,and risk of all-cause mortality:A prospective cohort study of 282

<正>In 2022, Duncan et al.¹ published results from an investigation of the combined effects of moderate-to-vigorous aerobic exercise(AER), muscle-strengthening activities(MSA), and sleep durations on the risks for all-cause mortality in 282,473 U.S. adults aged 18—84 years.     

The influence of self-determination in physical education on leisure-time physical activity behavior

Using a multitheory approach, this study was designed to investigate the influence of urban adolescents' perceived autonomy and competence in physical education on their physical activity intentions and behaviors during leisure time. A transcontextual model was hypothesized and tested. Urban adolescents (N=653, ages 11-15 years) completed questionnaires assessing relevant psychological constructs and moderate to vigorous physical activity and then had their cardiorespiratory fitness assessed with the Progressive Aerobic Cardiovascular Endurance Run (PACER) test. Based on our structural equation modeling analyses and fit indexes, the transcontextual model adequately fit the data. We concluded that the two theoretical frameworks--SDT and theory of planned behavior--can be integrated to provide an enhanced understanding of the influence of physical education on leisure-time physical activity. The results revealed that perceived autonomy and competence in physical education are interrelated and function as a whole for enhancing leisure-time physically active intentions and behavior.     

Exploring overweight and obesity beyond body mass index: A body composition analysis in people with and without patellofemoral pain

BackgroundWe compared body mass index (BMI), body fat, and skeletal muscle mass between (1) a mixed-sex nonathletic cohort of people with patellofemoral pain (PFP) and pain-free people, and (2) a nonathletic cohort of people with PFP and pain-free people subgrouped by sex (i.e., men and women with PFP vs. pain-free men and women).MethodsThis cross-sectional study included 114 people with PFP (71 women, 43 men) and 54 pain-free controls (32 women, 22 men). All participants attended a single testing session to assess body composition measures, which included BMI, percentage of body fat (%BF_Bioimpedance), and skeletal muscle mass (both assessed by bioelectrical impedance analysis), and percentage of body fat (%BF_Skinfold) (assessed by skinfold caliper analysis). A one-way univariate analysis of covariance (age and physical activity levels as covariates) was used to compare body composition measures between groups (i.e., PFP vs. pain-free group; women with PFP vs. pain-free women; men with PFP vs. pain-free men).ResultsWomen with PFP presented significantly higher BMI, %BF_Bioimpedance, and %BF_Skinfold, and lower skeletal muscle mass compared to pain-free women (p ≤ 0.04; effect size : ‒0.47 to 0.85). Men with PFP and men and women combined had no differences in BMI, %BF_Bioimpedance, %BF_Skinfold, and skeletal muscle mass compared to their respective pain-free groups (p > 0.05).ConclusionOur findings indicate that BMI and body composition measures should be considered as part of the evaluation and management of people with PFP, especially in women, who have demonstrated higher BMI and body fat and lower skeletal muscle mass compared to pain-free controls. Future studies should not assess body composition measures in a mixed-sex population without distinguishing men participants from women participants.