Exercise can improve physical self perceptions in adolescents with low motor competence.

Adolescents with low motor competence have diminished perceptions of their physical self and tend to avoid physical activities. This study examined the outcomes of an exercise intervention that focused on improving aerobic fitness, strength, and self-perceptions in the physical domain in adolescents with poor motor coordination. The sample included 35 adolescents with low motor competence, comprising boys (n = 25) and girls (n = 10) ranging in age from 13 to 17 years, who attended two sessions per week in the 13 week exercise intervention study (AMP it up). Physical self-perceptions were measured before and after the intervention using the Physical Self Perception Profile and Perceived Importance Profile. Significant improvements in perceived Physical Condition, Attractive Body and Physical Strength sub domain scores were identified between pre and post-test. Adjusting for age, gender, BMI and attendance, regression analyses revealed that Attractive Body was the strongest predictor of Physical Self Worth at pre-test, joined by Physical Condition at post-test. This exercise intervention had a positive impact on adolescent physical self-perceptions, in particular males, with improvements in those sub domains specifically related to the exercise program. Changes in specific aspects of Physical Self Worth can be facilitated by exercise interventions, after a relatively short period of time, in adolescents with poor motor coordination.

Reprint of 'The psychometric properties of the McCarron assessment of neuromuscular development as a longitudinal measure with Australian youth'.

The importance of considering age and sex differences in the assessment of motor performance has been largely overlooked. This study examines the psychometric properties of the US developed McCarron Assessment of Neuromuscular Development (MAND) using data from a longitudinal sample of 986 Australian youth at 10, 14 and 17 years. A key finding was the sex and age interaction of the Neuromuscular Developmental Index (NDI) (F=121.46, p<.001). Males had a significantly lower mean NDI score at 10 years and the females had a lower score at 17 years. The factor structure differed from the US samples (McCarron, 1997) at each age and between males and females. The sex specific analyses showed that the underlying structure was more complex for younger females. Although the MAND remains a useful test of motor performance for Australian children, further consideration is warranted regarding sex differences, the relevance of the US based normative tables and factor structures.

Low motor performance scores among overweight children: poor coordination or morphological constraints?

This study examined whether lower motor performance scores can be full attributed to poor coordination, or whether weight related morphological constraints may also affect motor performance. Data for 666 children and adolescents from the longitudinal Western Australian Pregnancy Cohort (Raine) Study were grouped into normal weight, overweight and obese categories based on the International Obesity Task Force cut points. Participants completed the 10-item McCarron Assessment of Neuromuscular Development (MAND) at the 10 and 14 year follow-up. The prevalence of overweight and obese participants classified with mild or moderate motor difficulties was not different from the normal weight group at 10 years (χ2 = 5.8 p = .215), but higher at 14 years (χ2 = 11.3 p = .023). There were no significant differences in overall motor performance scores between weight status groups at 10 years, but at 14 years, the normal weight group achieved better scores than the obese group (p<.05). For specific items, the normal weight group consistently scored higher than the overweight and obese groups on the jump task at 10 (p<.001) and 14 (p<.01)years but lower on the hand strength task at both ages (p<.01). Our findings raise the question as to whether some test items commonly used for assessing motor competence are appropriate for an increasingly overweight and obese population.

The psychometric properties of the McCarron Assessment of Neuromuscular Development as a longitudinal measure with Australian youth.

The importance of considering age and sex differences in the assessment of motor performance has been largely overlooked. This study examines the psychometric properties of the US developed McCarron Assessment of Neuromuscular Development (MAND) using data from a longitudinal sample of 986 Australian youth at 10, 14 and 17 years. A key finding was the sex and age interaction of the Neuromuscular Developmental Index (NDI) (F=121.46, p<.001). Males had a significantly lower mean NDI score at 10 years and the females had a lower score at 17 years. The factor structure differed from the US samples (McCarron, 1997) at each age and between males and females. The sex specific analyses showed that the underlying structure was more complex for younger females. Although the MAND remains a useful test of motor performance for Australian children, further consideration is warranted regarding sex differences, the relevance of the US based normative tables and factor structures.

The associations between physical activity, screen time and weight from 6 to 14 yrs: the Raine Study.

To examine the strength and direction of the relationship between physical activity level, screen use and BMI in a cohort at ages 6, 8, 10 and 14 yrs as part of a prospective longitudinal cohort study. The sample comprised 1403 males and females who participated in the follow-up survey at 14 yrs of age between 2003 and 2005. Exploratory structural equation modelling was used to examine the interrelationships between physical activity level, BMI and screen time at 6, 8, 10 and 14 yrs. Predictors of BMI at 6, 8, 10 and 14 yrs explained 1.3, 76.1, 80.1 and 73.1 percent of the variances, respectively, with previous BMI the largest predictor [χ(2)=43.082, df=36, p=194]. Increased screen time predicted higher BMI and lower physical activity at 8 and 10 yrs but not 14 yrs. At 14 yrs, physical activity predicted BMI. Sedentary patterns of behaviour in early childhood were predictive of later and concurrent obesity, whereas physical activity was predictive of obesity in adolescence. Different intervention targets are required for children and adolescents.

Evidence for the validity of the Children's Attraction to Physical Activity questionnaire (CAPA) with young children.

Attraction to physical activity is important to an individual's intrinsic motivation to engage in play, games and sports. While there are instruments designed to measure attraction to physical activity in middle childhood years, the lack of authentic measures in young children has impeded research in this area. In this study we sought to address the validity of a scale to tap young children's attraction to physical activity. Evidence for validity was based on internal consistency, content analysis, and factor structure. Australian school children (180 boys and 154 girls) from school year two, aged 6-8 years, were individually administered a modified version of the Children's Attraction to Physical Activity Scale (CAPA) [Brustad RJ. Who will go out to play? Parental and psychological influences on children's attraction to physical activity. Pediatr Exerc Sci 1993;5:210-23; Brustad RJ. Attraction to physical activity in urban school children: parental socialization and gender influences. Res Q Exerc Sport 1996;67:316-23]. The results indicated that internal consistency was acceptable for most of the subscales when negative statements were excluded from the analyses. Factor analysis revealed that the liking of games and sports, liking of physical exertion and exercise, and the importance of exercise subscales were more robust. Second order factor analysis indicated that the overall construct of attraction to physical activity was viable in this age group. With some modifications, the scale appears to provide a valid approach to the measurement of attraction to physical activity in young children.

Intra-individual variation in children's physical activity patterns: Implications for measurement.

Children's physical activity (PA) patterns change from day to day. This intra-individual variability affects precision when measuring key physical activity and sedentary behaviour variables. This paper discusses strategies used to reduce the random error associated with intra-individual variability and demonstrates the implications for assessing PA when varying number of days are sampled. Self-reported data collected on two hundred and ninety eight 13-14-year-olds were used to compare estimates of PA and sedentary behaviour derived from between 1 and 7 days of recall data. Large intra-individual coefficients of variation were calculated for physical activity level (14.5%), moderate-to-vigorous physical activity (83.4%), screen time (60.8%) and sleep (12.2%). While the magnitude of error associated with estimating means decreased as more days were sampled, the paper notes that depending on the nature of the research question being asked, sampling fewer days may yield sufficiently precise estimates. Therefore, researchers should conduct power analyses based on estimated inter- and intra-individual variability and sample size to determine how many days to sample when assessing children's PA patterns.

Increased associated movements: influence of attention deficits and movement difficulties.

This study was designed to examine whether increased associated movements (AMs) reflect motor difficulties or the symptoms associated with attention disorders. Four groups of male children (N=51) aged 6-8 years participated: Group 1 consisted of 13 children diagnosed with developmental coordination disorder (DCD); Group 2 consisted of 13 children diagnosed with attention deficit hyperactivity disorder (ADHD); Group 3 consisted of 10 children diagnosed with co-occurring DCD and ADHD, and Group 4 was a control sample of 15 children, with no known movement or attention difficulties. Various AM tasks were selected from established assessments and previous research to measure AM severity. The results supported the hypothesis that increased severity of AMs reflect movement difficulties with children in the DCD and DCD/ADHD groups displaying significantly more AMs than children in the ADHD and control groups (p<.001). No differences were found between the ADHD only and control groups (p=.67) or the DCD and DCD/ADHD groups (p=.81) suggesting that AM severity is not influenced by the neurodevelopmental symptoms associated with ADHD.

Activities of daily living in children with developmental coordination disorder: dressing, personal hygiene, and eating skills.

In order to understand how age, culture, and problems in motor coordination impact the performance of activities of daily living, we used focus groups and in-depth interviews with Australian and Canadian parents to examine activities of daily living of younger (5-7 years of age) and older (8-9 years of age) children with and without DCD. By comparison with their typically developing age group, children with DCD had more difficulty with dressing, personal hygiene, and eating skills. Difficulties with postural control and fine-motor skills were reported to contribute to poorer performance of activities of daily living. As expected, competence in the performance of activities of daily living improved in the older children with and without DCD and there were few differences in the performance of daily living tasks between typical children in Australia and Canada. Overall, the motor difficulties of children with DCD had a significant impact on performance of a wide range of daily activities.

The influence of developmental coordination disorder and attention deficits on associated movements in children.

The relationship between associated movements (AMs) and level of motor performance is not well understood. In this study we investigated whether children with developmental coordination disorder (DCD), with (n = 10) and without (n = 10) attention deficit hyperactivity disorder (ADHD), and a control group (n = 10), differed in the severity of AMs. A total AM severity score was obtained for each child by rating their performance on AM tasks. Both groups with motor difficulties had significantly more severe AMs than the control group. A significant correlation was found between level of motor performance and total AM scores (r = -.62). Our results suggest that level of motor performance should be considered in future research attempting to understand individual differences in severity of AMs as a function of motor, learning, and behavioural disorders.

Perceived Competence, Discrepancy Scores, and Global Self-Worth.

According to Harter (1985a), global self-worth (GSW) can be predicted from the relationship between perceptions of competence and importance ratings. In this study, we employed Harter's (1985b) Importance Rating Scale (IRS) and Self-Perception Profile for Children (SPPC) to examine importance ratings, discrepancy scores, and domain-specific perceptions of competence as predictors of GSW. Children (N = 130, 62 boys and 68 girls) aged 8-12 years were categorized into high (HMC; n = 62) and low motor coordination (LMC; n = 68) groups according to their scores on a motor proficiency battery (McCarron, 1982). Regression analyses using domain-specific perceptions of competence, importance, and discrepancy scores confirmed that self-perception ratings were the best predictors of GSW. For both groups, perceptions of physical appearance, social acceptance, and behavioral conduct contributed significantly to prediction of GSW. By contrast, perceived athletic competence increased prediction of GSW for the HMC group but not the LMC group.