A Multi-Method Multi-Analytic Approach to Establishing Internal Construct Validity Evidence: The Sport Multidimensional Perfectionism Scale 2

The purpose of the study was to examine the norm-referenced and criterion-referenced reliability and validity of the Back-Saver Sit-and-Reach Test (BSR; Single-Leg Sit-and-Reach; Cooper Institute for Aerobics Research [CIAR], 1999). One hundred seventy-nine elementary school children (87 boys and 92 girls), 6-12 years old participated, with 44 randomly selected participants retested on a second day. The BSR, Modified Schober (MSCH, Low Back Criterion Test), Passive Straight Leg Raise (PSLR, Hamstring Criterion Test), Active Knee Extension, True Lumbar Extension, True Lumbar Flexion, and Double-Leg Sit-And-Reach were administered in random order. Intraclass correlation coefficients (norm-referenced reliability) for the BSR were extremely high (.98-.99) for both boys and girls. Pa and Km (criterion-referenced test-retest reliability) for the right leg was .90 and .80, respectively, for boys; and .91 and .82 for girls, indicating the participants were classified consistently across days. Norm-referenced validity coefficients (Pearson product-moment correlations, r) of the BSR as a measure of hamstring flexibility were moderate for boys (.67 and .68, right and left legs, respectively) and moderately low for girls (.47 and .44, right and left legs). Correlation coefficients of the BSR as a measure of low back flexibility were extremely poor for boys and girls, with coefficients ranging from .003 to .06. Criterion-referenced validity of BSR for hamstring flexibility was low and unacceptable for right and left legs (Km: .48, .58, respectively), for both boys and girls (Km: .40, .22). The BSR appears to be similar to the Double-Leg Sit-and-Reach in that it is a test of hamstring flexibility but not low back. The criterion-referenced standards for both BSR and PSLR should be re-examined and adjusted to provide a better degree of classification agreement between the BSR and the criterion measure (PSLR).     

Reliability of the Trunk Lift in High School Boys and Girls

The purpose of this study was to examine the reliability of the trunk lift test. Eighty eight high school boys and girls performed two trials of the trunk lift test as described in the FITNESSGRAM manual (Cooper Institute for Aerobics Research, 1992) on each of 2 days. Intraclass correlation coefficients were used to examine norm-referenced reliability, whereas P and modified kappa (κ_m) were used to examine criterion-referenced reliability. Additionally, a goniometer was used to examine the relationship between the trunk lift test and trunk range of motion. Reliability ranged from R = .93 to .98 with estimated reliability of R = .90 for boys and R = .85 for girls for a single trial test. Using 9 inches as the cutoff score, P was .93 with κ_m = .86 for boys, whereas for girls both P and κ_m were 1.0. Specifically, 93% of boys and 100% of girls passed the trunk lift test on both days. The correlation between trunk lift scores and goniometer scores was r = .70 for boys and r = .68 for girls. These results suggest that the trunk lift test is a simple and highly reliable test. However, the concurrent validity of the trunk lift test and the validity of the cutoff score used for this test need to be determined. Finally, the relationship between low back pain and trunk lift scores needs to be examined.     

不同生源大学新生体质状况的研究分析

为探讨不同生源的大学新生的体质状况,以3 653名大学一年级学生为研究对象,采用实验测试法按照《国家学生体质健康标准》的要求进行测试研究。结果发现:①城镇生源的大学新生在身高、体重等测试项目上显著性大于农村生源的大学新生(P<0.05),而农村生源的大学新生在耐力项目得分、坐位体前屈、立定跳远和总得分等测试项目上非常显著高于城镇生源的大学新生(P<0.01)。②城镇生源的大学新生中女性同学在肺活量测试项目非常显著大于农村生源大学生(P<0.01),而在800m测试、坐位体前屈、立定跳远和总得分等方面农村生源的女性新生显著高于城镇生源的女性新生(P<0.01)。③城镇生源的大学新生中男性在身高、体重、肺活量等测试项目非常显著高于农村生源的男性(P<0.01),而在1 000m测试、坐位体前屈和总得分等测试项目农村生源的男性新生非常显著高于城镇生源的男性新生(P<0.01)。结论:农村生源大学新生的体质显著性好于城镇生源大学新生,但城市生源大学新生的身高、体重的显著性高于农村生源大学新生。生活的环境、应试教育和对困难的认知能力是造成此结果的主要因素。     

Squat Jump Performance During Growth in Both Sexes

The purpose of this cross-sectional study was to investigate leg muscle power and compare two activities (jumping and cycling) in 383 girls and 407 boys ages 9–19 years. Results in anthropometric characteristics and jumping performance were comparable until midadolescence, and sex differences were observed. Lean leg volume (LLV) was the reason for most of the variance (76% in girls and 88% in boys) in jumping performance. However, the LLV exponent was higher than expected in boys but not girls. Therefore, unidentified qualitative changes of muscle function during growth in boys must be considered. The squat jump index (SJI) was highly correlated to cycling peak power (CPP; N = 790, r = .94, p < .001). Although prediction error of CPP from SJI was less than 5% when considering each sex-and-age group, individual errors mounted to 40%. Due to its practicability, SJI is recommended in large-scale developmental prospective studies. However, cycling and jumping protocols are not interchangeable when measuring peak power values.     

Validation of a short physical activity recall questionnaire completed by Spanish adolescents

Abstract

Self-report recall questionnaires are commonly used to measure physical activity in children and adolescents. However, they have been shown to have low to moderate validity, mainly due to inaccuracies in recall activity. The purpose of the present study was to determine the reliability and validity of an adapted version of the Assessment of Physical Activity Levels Questionnaire (APALQ) among a sample of Spanish adolescents. Test–retest reliability of the APALQ was assessed using a sample of 150 adolescents (72 males, 78 females), aged 13.6±1.1 years, who answered the APALQ twice within 7 days. Criterion validity was assessed using a sample of 77 adolescents (50 males, 27 females), aged 13.6±1.1 years, by comparing the APALQ against the Computer Science and Application (CSA) monitor. All participants were volunteers recruited from local schools in the Aragon region of Spain. Test–retest reliability for all items was high with intra-class coefficients of 0.77 for boys and 0.74 for girls. The APALQ demonstrated modest criterion validity with Pearson correlation coefficients (r) ranging from 0.53 between Physical Activity Index (PAI) and CSA minutes of moderate and vigorous physical activity, and 0.47 between PAI and CSA steps per day. When the data were analysed by gender, girls had higher correlations than boys (P < 0.01). The Spanish APALQ seems to be a valid and reliable short self-report physical activity questionnaire.     

Psychometric properties of child- and teacher-reported curl-up scores in children ages 10-12 years

The purpose of this study was to examine the psychometric properties of child- and teacher-reported curl-up (CU) scores in children ages 10-12 years in both a norm-referenced (NR) and criterion-referenced (CR) framework. Eighty-four children, 36 boys and 48 girls, performed the FITNESSGRAM (Cooper Institute for Aerobics Research, 1992) CU test on 2 days separated by 48-72 hr. Two video cameras were used to record students' CU performances. Two students performed the CU at the same time, with each child's performance recorded by one camera. The test was terminated when the child stopped due to fatigue or after two form errors occurred. Teacher-reported scores were the average of two independent ratings of each video performance, while child-reported scores came from data collected and recorded by the children. Single trial norm-referenced reliability was R = .75 for girls and R = .80 for boys for teacher-reported CU and R = .69 and R = .70 for child-reported CU for girls and boys, respectively. CR reliability was examined using P, proportion of students who consistently passed or failed the test across 2 days, and km, defined as reliability with chance removed. For teacher-reported scores, P = .89 and km = .78 for boys and P = .81 and km = .62 for girls. For child-reported scores, P = .86 and km = .72 for boys, while P = .79 and km = .58 for girls. For teacher-reported data, 39% of boys passed and 50% failed the test on both days, while for girls the percentages were 27% pass and 54% fail. For child-reported data, 64% of boys passed and 22% failed on both days, while 54% of girls passed and 25% failed. NR validity was examined by correlating teacher and child-reported scores. The resultant coefficient was r = .42 (95% CI = .11-.66) for boys and r = .67 (95% CI = .58-.74) for girls. Additionally, child-reported scores were significantly higher than teacher-reported scores. CR validity was examined with a contingency coefficient, and results indicated C = .55 with 44% false master errors for boys and C = .65 with 29% false master errors for girls. The findings of this study suggest that while NR reliability estimates were moderate for teacher-reported scores, single trial estimates suggest that child-reported CU should be viewed with caution. In regard to CR reliability, both teacher-reported and child-reported reliability were moderate. However, there were marked differences between teacher- and child-reported scores, with children reporting higher percentages of students passing and lower percentage of student failing the test when compared with scores reported by teachers. Validity was rather moderate when viewed in either a NR and CR framework. It is suggested that problems with child-reported scores may be due to the need for additional practice or simplification of the testing protocol.     

The Determination of the Weight and Size of a Standard Discus for College Women

Abstract

The purpose of this study was (1) to determine the relationship between roentgenographic measures of muscle size of the leg and ankle extensor strength of 51 seven-year-old children, and (2) to examine sex differences in strength and leg muscle size at this age level. The correlations between ankle extensor strength and the measures of leg muscle size ranged between .58 and .63 for the boys and between .22 and .52 for the girls. The boys were substantially stronger than the girls in ankle extensor strength (P = .02) and possessed on the average the greater muscle size. When boys and girls were paired on the basis of measures of muscle size, the superiority of the boys in strength was significant at only the 30-per-cent level of confidence.     

Validity and feasibility of an obstacle course to assess fundamental movement skills in a pre-school setting

Failure to master age-appropriate fundamental movement skills (FMS) at a young age can limit motor skill competence affecting health. Assessments often have issues with feasibility and implementation in a field setting. As such, the purpose of this study was to investigate the validity and feasibility of the Athletic Skills Track (AST), in a pre-school setting. For the validation study sixty-five 3–6 year old children (25 boys and 40 girls) from five pre-schools across Adelaide, Australia participated. Correlations and linear regression analysis (adjusted for age and gender) were used to investigate the association between the time to complete the AST and the raw score of the Test of Gross Motor Development 2 (TGMD-2). For the feasibility study pre-school staff completed a semi-structured interview regarding the feasibility of the AST. The AST took less than a minute per child and the TGMD-2 around 20 minutes for two children. There was a strong negative correlation (r = ?0.63, p < 0.01) between the AST scores and the TGMD-2 scores. All five staff reported strengths of the AST to be its short administration time, setup and appropriateness. These results suggest that the AST could be a feasible and valid method of FMS assessment in Australian pre-schools.     

Relations among basic psychological needs,PE-motivation and fundamental movement skills in 9–12-year-old boys and girls in Physical Education

Background: Many children aged 9–12 appear to have low levels of fundamental movement skills (FMS). Physical education (PE) is important because PE-teachers can teach children a variety of FMS and can influence PE-motivation. However, declined levels of PE-motivation are reported in the final grades of elementary school. Therefore, more insight in the relations between PE-motivation and FMS is needed.

Purposes: In the first phase, instruments to measure the satisfaction of basic psychological needs (competence, autonomy, classmate relatedness and teacher relatedness) and PE-motivation (autonomous and controlled) in 9–12-year-old children were developed and validated. The purpose of the second phase was to examine the influence of basic psychological needs on PE-motivation, the influence of PE-motivation on locomotor skills, object control skills and balance skills, and the direct influence of basic psychological needs on FMS for boys and girls aged 9–12.

Participants and data collection: In the first phase, 172 children (82 boys, 90 girls, M?=?10.72 years?±?0.77) filled out questionnaires assessing the satisfaction of their basic psychological needs and motivation for PE. Forty-eight children completed the questionnaires again 4 weeks later. In the second phase, a total of 138 children (66 boys, 72 girls, 10.8 years?±?.79) (three schools from phase 1 and one new school) participated. Children from the new school also completed the questionnaires and all children conducted the subtest for speed and agility, upper limb coordination and balance of the Bruininks-Oseretsky Test of Motor Proficiency 2.

Data analysis: In phase 1, linear weighted Kappa's and the Mokken Scale Program for polychotomous items were used to test reliability and validity. In phase 2, Pearson's correlations and multiple linear regression analyses were performed to examine the relations.

Findings: Regarding phase 1, all subscales were reliable and the validity was considered moderate to strong except for the autonomy subscale, which was not reliable and valid. With respect to phase 2, all basic psychological needs, except autonomy among girls, had moderate to strong correlations with autonomous PE-motivation. Teacher relatedness was the most important predictor for boys and girls, while the second predictor was classmate relatedness for boys and competence for girls. No positive significant relations between basic psychological needs and FMS and between PE-motivation and FMS were found. In contrary, moderate but negative relations between teacher relatedness and balance skills and between autonomous PE-motivation and balance skills were found for boys.

Conclusions: The results confirmed the importance of the basic psychological needs in the prediction of autonomous PE-motivation in 9–12-year-old children. Although all needs should be supported by the PE-teacher, it is important to be aware of the different impact of the needs on autonomous PE-motivation for boys and girls. Despite the missing relations with FMS, PE-teachers seem to be able to autonomously motivate children for PE regardless of their FMS proficiency.     

Utility of international normative 20 m shuttle run values for identifying youth at increased cardiometabolic risk

The purpose of this study was to examine the ability of international normative centiles for the 20 m shuttle run test (20mSRT) to identify youth at increased cardiometabolic risk. This was a cross-sectional study involving 961 children aged 10–17 years (53% girls) from the United Kingdom. Receiver operating characteristic (ROC) curves determined the discriminatory ability of cardiorespiratory fitness percentiles for predicting increased cardiometabolic risk. ROC analysis demonstrated a significant but poor discriminatory accuracy of cardiorespiratory fitness in identifying low/high cardiometabolic risk in girls (AUC = 0.58, 95% CI: 0.54–0.63; p = 0.04), and in boys (AUC = 0.59, 95% CI: 0.54–0.63; p = 0.03). The cardiorespiratory fitness cut-off associated with high cardiometabolic risk was the 55^th percentile (sensitivity = 33.3%; specificity = 84.5%) in girls and the 60^th percentile (sensitivity = 42.9%; specificity = 73.6%) in boys. These 20mSRT percentile thresholds can be used to identify children and adolescents who may benefit from lifestyle intervention. Nonetheless, further work involving different populations and cardiometabolic risk scores comprising of different variables are needed to confirm our initial findings.     

The Stability of Perceived Motor Competence of Primary School Children from Two Countries over One Year

ABSTRACT

Children’s positive perceived motor competence (PMC) provides motivation for physical activity. Theoretically young children (<8 years) have inflated PMC but as children cognitively develop, perceptions are hypothesized to decrease. This study investigated strength of PMC association over time, whether any change was negative (i.e. PMC decreased) and sex differences. A total of 198 children participated, 88 (44.4%) girls and 110 (55.6%) boys, aged 8.37–11.3 years at time point one (T1). Test–retest reliability using intraclass correlation was moderate for locomotor and moderate-to-good for object control perception. Hierarchical regression analysis showed PMC at T1 positively predicted significant variance one year later (T2) for locomotor (23.1%) and object control skill (5 items: 37.7%; 7 items: 39.9%). Whilst boys and girls differed on perception level there was no interaction between PMC and sex. Incongruent with previous theoretical perspectives this study identified stability in children’s PMC across an important developmental period.     

Gross Motor Competence and Peak Height Velocity in 10- to 14-Year-Old Canadian Youth: A Longitudinal Study

The objective of this study was to evaluate gross motor competence and growth spurt in Canadian youth. Eighty-two children (38 boys, 44 girls) were assessed over a time period of five years. Growth rate was measured quarterly; motor competence was evaluated once per year using the Bruininks-Oseretsky Test of Motor Proficiency. Peak height velocity (PHV) occurred at a significantly younger age in the girls (11.3 ± 0.4 years) than the boys (13.4 ± 0.3 years; p < .001), and growth rate during PHV was significantly greater in the boys than the girls (2.8 ± 1.3 vs. 2.0 ± 0.7 cm/quarter; p = .003). Gross motor competence outcomes were significantly above the North American normative scores (p < .05) over the measured time period. After the occurrence of PHV, strength, strength/agility, and gross motor skill significantly decreased in girls (p < .01), and running speed/agility significantly decreased in boys (p < .05). This finding emphasizes that motor competence in pre-adolescent children may suddenly decrease after their growth spurt.     

功能性动作筛查（FMS）在普通成老年人群中的应用

目的：通过功能性动作筛查,对普通成老年人群身体功能性运动能力的特征进行评价分析,初步探索FMS在普通人群体质测评中的应用。方法：对481名20~69岁成老年人群（男209名,女272名）进行FMS,包括深蹲、栏架跨、直线蹲、肩部灵活性、直腿抬高、俯撑、体旋稳定性7个动作模式,满分为21分。结果：FMS总分女性（14.2）明显高于男性（13.7）;深蹲、直线蹲、俯撑3项得分均为男性明显高于女性,肩部灵活性、直腿抬高、体旋稳定性得分则为女性明显高于男性;无论男女,40岁之后,随着年龄的增长,FMS总分均呈下降态势;女性深蹲、直线蹲、俯撑得1分的比例（46.3%、28.5%、13.6%）明显高于男性（33.5%、12.6%、3.5%）,女性肩部灵活性、直腿抬高得3分的比例（58.1%、53.7%）明显高于男性（23.6%、18.2%）;男性（26.8%）FMS非对称性测试结果阳性率略高于女性（23.5%）;无论男女,大部分受试者FMS总分在14~18之间（良好）,男性不及格比例（41.1%）高于女性（36.0%）。结论：女性身体功能性运动能力略好于男性,其中柔韧能力相对突出;部分人群身体/肢体两侧功能性运动能力不对称,其中肩关节活动范围两侧差异最为明显;年龄是影响身体功能性运动能力的重要因素。建议将FMS作为体质测评的补充内容。     

山西省3-6岁幼儿身体素质发展规律对幼儿武术教学的启示

幼儿3-6岁的体育教学,对早期培养以灵敏、速度、快速力量、协调、平衡等为能力要求的竞技体育武术项目高水准运动员的成才很重要。文章根据2005年山西省国民体质监测幼儿身体素质坐位体前屈、10米折返跑、立定跳远、双脚连续跳、平衡木五项身体素质指标的测试结果中所反映出的3-6岁幼儿时期：在性别遗传方面,柔韧、速度、力量素质有明显差异,协调、平衡能力差别不大和6项素质均存在自然增长快的年龄段的身体素质自然增长规律。提出在3-6岁幼儿武术体育教学中,对男女幼儿的柔韧素质、速度素质、跳跃素质应区别对待,对协调性素质、平衡素质,男女幼儿的武术体育教学,应当安排一致。     

Recreational activities and motor skills of children in kindergarten

Background: Developmental theorists suggest that physical activity during early childhood promotes fundamental motor skill (FMS) proficiency; and that differences in FMS proficiency are largely related to children's experiences.

Aim: To examine associations between participation in different types of recreation/leisure and FMS proficiency of boys and girls in their first year of school. We hypothesized that there would be positive associations between FMS proficiency and participation in organized sport, physical activities, and active physical recreation; but not for other types of recreation/leisure.

Method: Participants (n?=?74) were kindergarten children (Mage?=?5y11?m; boys?=?55%). Parents completed the diversity dimension of the Children's Assessment of Participation and Enjoyment (CAPE) survey. The CAPE measures children's participation in everyday activities outside of mandated school activities in the past four months in five types of formal and informal activities, specifically: Recreational activities, Physical activities, Social activities, Skill-Based activities, and Self-Improvement activities. Two categories of activities were also reported: Organized Sport and Active Physical Recreation. Locomotor and object control skills were assessed using the Test of Gross Motor Development-2 and static balance was assessed using a stork stand. Sex-based differences in motor skills and participation were examined using chi-squared analyses. Correlation coefficients were used to examine relationships between motor skills and CAPE sub-domains and categories. Linear regression was used to examine whether the type of activity predicted motor skill proficiency and the reverse.

Results: There were no sex-based differences in locomotor skills; whereas boys' object control skill scores were significantly higher than girls, and girls' stork stand scores were higher than boys'. Although there were no sex-based differences in the more active categories of recreational pastimes; girls participated in significantly more formal and informal dance and the prevalence of participation in team sports was significantly higher for boys. For boys, participation in physical activities predicted both locomotor and object control skill scores, organized sport predicted object control skills, and active recreation predicted stork stand times and object control skill scores. These relationships were not evident among the girls.

Conclusions: These findings illustrate that young children participate in a narrower array of physically active recreational pursuits compared with less active pursuits. There were notable sex-based differences in the relationships between participation and motor skill proficiency. For girls, none of the associations between recreational pastimes and motor skill proficiency were significant. This suggests that the motor proficiency of girls, as assessed in this study, is neither a precursor to, nor an outcome of, participation in active recreational pastimes. Contrastingly, the findings for boys support theory that suggests that physical activity is driving the acquisition of particular types of motor skills. Less active recreational activities were not associated with motor skill levels of boys, whereas each of the more active categories of recreational pastimes (active recreation, physical activities, and organized sport) predicted at least one sub-type of motor skill. It also seems clear from our findings that more light needs to be shed on how to optimally portray young girls' motor skill proficiency; as well as the relationships between their participation and motor skills.     

Relationship between abdominal adiposity,cardiovascular fitness,and biomarkers of cardiovascular risk in British adolescents

BackgroundPuberty is a critical time in the development of overweight and obesity. The aim of this study was to examine relationships between measures of adiposity, cardiovascular fitness, and biomarkers of cardiovascular disease risk in adolescents.MethodsIn a cross-sectional study design, 129 girls and 95 boys aged 12.9–14.4 years at various stages of puberty were included, along with their mothers (n = 217) and fathers (n = 207). Anthropometric assessments of adiposity were made, along with cardiovascular physical fitness, using the 20-m shuttle run test, and biomarkers associated with cardiovascular risk, including glucose, insulin, triglyceride, fibrinogen, and C-reactive protein (CRP) concentrations.ResultsWaist-to-height ratio values were similar in boys and girls and correlated positively with diastolic blood pressure, insulin, triglyceride, fibrinogen, and CRP concentrations, and inversely with cardiovascular fitness scores. Skinfold thickness measurements were higher in girls. High-molecular-weight adiponectin concentrations were lower in boys than girls, particularly in late puberty, and CRP levels were higher. Cardiovascular fitness, maternal body mass index (BMI), and paternal BMI contributed independently to the variance in waist measurements in girls and boys. Gender, triceps skinfold thickness, and weight-to-height ratio, but not parental BMI, contributed independently to the variance in cardiovascular fitness.ConclusionThere is a relationship between measures of adolescent adiposity and parental weight that involves factors other than cardiovascular fitness. Adolescent boys have relatively more abdominal fat than girls and a tendency to have a proinflammatory profile of biomarkers. These observations suggest that family and social environmental interventions are best undertaken earlier in childhood, particularly among boys.     

Prized Performers,but Frequently Overlooked Students: The Involvement of Black Athletes in Intercollegiate Sports on Predominantly White University Campuses, 1890-1972

This review assembles pedometry literature focused on youth, with particular attention to expected values for habitual, school day, physical education class, recess, lunch break, out-of-school, weekend, and vacation activity. From 31 studies published since 1999, we constructed a youth habitual activity step-curve that indicates: (a) from ages 6 to 18 years, boys typically take more steps per day than girls; (b) for both sexes the youngest age groups appear to take fewer steps per day than those immediately older; and (c) from a young age, boys decline more in steps per day to become more consistent with girls at older ages. Additional studies revealed that boys take approximately 42–49% of daily steps during the school day; girls take 41–47%. Steps taken during physical education class contribute to total steps per day by 8.7–23.7% in boys and 11.4–17.2% in girls. Recess represents 8–11% and lunch break represents 15–16% of total steps per day. After-school activity contributes approximately 47–56% of total steps per day for boys and 47–59% for girls. Weekdays range from approximately 12,000 to 16,000 steps per day in boys and 10,000 to 14,000 steps per day in girls. The corresponding values for weekend days are 12,000–13,000 steps per day in boys and 10,000–12,000 steps per day in girls.     

Injuries during football tournaments in 45,000 children and adolescents

Four percent of the world’s population, or 265 million people, play football, and many players are injured every year. The present study investigated more than 1800 injuries in over 45,000 youth players participating in three consecutive international football tournaments in Denmark in 2012–2014. The aim was to investigate the injury types and locations in children and adolescent football players and the differences between genders and age groups (11–15 and 16–19 years of age). An overall injury rate of 15.3 per 1000 player hours was found. The most common injury location was lower extremities (66.7%), and the most common injury type was contusion (24.4%). Girls had a relative risk of injury of 1.5 compared with boys, p?p?p?相似文献   

Test–retest reliability of a battery of field-based health-related fitness measures for adolescents

Abstract

The main aim of this study was to determine the test–retest reliability of existing tests of health-related fitness. Participants (mean age 14.8 years, s = 0.4) were 42 boys and 26 girls who completed the study assessments on two occasions separated by one week. The following tests were conducted: bioelectrical impedance analysis (BIA) to calculate percent body fat, leg dynamometer, 90° push-up, 7-stage sit-up, and wall squat tests. Intra-class correlation (ICC), paired samples t-tests, and typical error expressed as a coefficient of variation were calculated. The mean percent body fat intra-class correlation coefficient was similar for boys (ICC = 0.95) and girls (ICC = 0.93), but the mean coefficient of variation was considerably higher for boys than girls (22.2% vs. 12.2%). The boys' coefficients of variation for the tests of muscular fitness ranged from 9.0% for the leg dynamometer test to 26.5% for the timed wall squat test. The girls' coefficients of variation ranged from 17.1% for the sit-up test to 21.4% for the push-up test. Although the BIA machine produced reliable estimates of percent body fat, the tests of muscular fitness resulted in high systematic error, suggesting that these measures may require an extensive familiarization phase before the results can be considered reliable.     

Children's physical activity and physical self-perceptions

The aim of this study was to determine the relationship between physical self-perceptions and physical activity in Canadian school children aged 10–14 years. The sample consisted of 220 boys and 246 girls in grades 5–8. Physical activity was assessed by 7-day recall using the Physical Activity Questionnaire for Older Children. Selfperceptions of physical conditioning, sports competence, strength, body appearance and general physical selfworth were measured by the Physical Self-Perception Profile (PSPP). We found that boys were more physically active than girls and had higher perceptions of sport competence and strength. All PSPP scales were significantly correlated with physical activity in both boys and girls. Structural equation modelling procedures found the hierarchical PSPP model provided a good fit to the observed data, with little evidence of diff erences between the sexes. Analysis of five alternative structural models of the relationship between the PSPP and physical activity found the most parsimonious model to have significant pathways from both physical conditioning and sport skills to physical activity. Models for the sample as a whole, for boys and for girls were similar, accounting for an R 2 of 0.27–0.29 for physical activity. Our results demonstrate that physical self-perceptions, especially physical conditioning and sport skills, are significant correlates of activity in this population.