ERA Health Sciences Peer Reviewed Conference Papers

Infammation and Altered Liver Function is Present in 13 Year Olds with Features of Metabolic Syndrome

Rae-Chi Huang et al. — Tue, 13 Apr 2010 02:13:05 PDT

Aims: Investigation of inflammation in Australian adolescents with features similar to the metabolic syndrome. Study design, Subjects and Outcome measures: A prospective longitudinal pregnancy cohort was followed up at 13 years. 1377 children underwent anthropometric, fasting lipid, insulin, inflammatory markers, liver function tests and blood pressure measurements. Cluster analysis defined a group at risk withfeatures akin to adult metabolic syndrome. One way ANOVA defined differences in hsCRP, uric acid, ALT and GGT in the cluster groups.

Results: The high risk group had higher BMI (x = 27.9, SD = 5.1 vs x = 20.2, SD = 2.6, p < 0.001), SBP (x = 120.1, SD = 12.0 vs x = 112.1, SD = 10.4, p < 0.001), insulin (x = 24.6, SD = 15.7 vs x = 10.2, SD = 4.6, p < 0.001), triglycerides (x = 1.5, SD = 1.0 vs x = 0.9, SD = 0.3, p < 0.001) and lower HDL (x = 1.2, SD = 0.3 vs x = 1.4, SD = 0.3, p < 0.001). Markers of inflammation and liver function were higher in the at risk group; hsCRP (x = 2.15, SD = 4.7 vs x = 0.7, SD = 2.7, p < 0.001), uric acid (x = 0.34, SD = 0.08 vs x = 0.29, SD = 0.06, p < 0.001), ALT (x = 21.23, SD = 9.7 vs x16.21, SD = 7.23, p < 0.001) and GGT (x14.6, SD = 5.9 vs x11.0, SD = 4.0, p < 0.001). The highest hsCRP levels were only present in children within the cluster who were also overweight.

Conclusions: This suggests that inflammation exists in at risk children as early as 13 years, preceding overt atherosclerosis. It provides clues to the pathogenesis of inflammation in cardiovascular disease by showing that neither being overweight or within the metabolic syndrome cluster alone is associated with raised CRP, but requires the combination of both. It supports early intervention for preventing childhood obesity and subsequent cardiovascular disease.

Co-Occurrence of Language and Motor Difficulties in Children

Dawne Larkin et al. — Mon, 12 Apr 2010 22:50:15 PDT

Background/Objective: Researchers have identified a high incidence of motor difficulties among children with language difficulties and attempted to elucidate the relationship between these problems. The research reported here explored: a) the incidence of motor problems among children with language difficulties; b) differences in motor performance between children with and without language difficulties; and c) which motor tasks were good predictors of language performance.

Methods: Data were obtained from a subsample of the longitudinal Western Australian Pregnancy Cohort (Raine) Study, collected at 10 years. The subsample included 836 boys and 769 girls. The total language score (TLS) of the Clinical Evaluation of Language Fundamentals (3rd ed.) (CELF) was used to identify a group with (TLS < 85) and a group without language difficulty (TLS >85). The neurodevelopmental index (NDI) from the McCarron Assessment of Neuromuscular Development battery measured motor performance. The five fine motor and five gross motor tasks, included in the battery, were used in 3 regression models to identify which motor tasks were the best predictors of CELF expressive, receptive and total language scores.

Results: The motor performance of the group with language difficulties was significantly lower (p< .001) than the group without language difficulties. Thirty nine percent (n = 144) of the group with language difficulties were identified as having motor difficulties (NDI < 85). The regression models were similar for all language variables and explained approximately 10% of the variance. Three manipulative tasks and a dynamic balance task made significant contributions to the prediction of the language scores.

Conclusion: This research provides further evidence of the high incidence of motor problems among children with language difficulties. The relationship between receptive and expressive language scores and motor performance reinforce the very general relationship between motor and language variables.

Symposium: Advances in Physical Activity and Psychological Well-being: International Perspectives

Bonnie Berger et al. — Thu, 08 Apr 2010 22:19:47 PDT

This symposium focuses on the relationships between physical activity and diverse aspects of psychological well-being. It also includes international perspectives on diverse populations and explores application of current theory in intervention programs designed to encourage more individuals to be physically active. A sedentary lifestyle is a major health hazard and is associated with coronary heart disease, hypertension, certain cancers, and type 2 diabetes (American College of Sports Medicine, 2006). In addition, individuals who are physically inactive do not have opportunities to reap or enjoy the somatopsychic benefits associated with physical activity such as feelings of global self-worth, a variety of self-concept dimensions such as physical appearance and social acceptance, mood alteration, enjoyment derived from using the body, decreases in social physique anxiety, and increases in life satisfaction. Insufficient physical activity detracts from subjective well-being and reflects a basic exercise dilemma: so many benefits, so few participants (Berger, 2004; Berger & Tobar, 2007)

Presenters will examine key psychological factors related to physical activity and/or its lack, and multiple aspects of psychological well-being in diverse populations throughout the world. These include adolescents at an orphanage in Mexico, young children in Australia in the public schools, adolescent African-American girls, and minority male and female youth from low-income backgrounds in the United States. Several of these populations tend to have low physical activity participation rates and are underserved in regard to exercise intervention programs.

Issues in the Identification of Developmental Coordination Disorder

Elizabeth Rose et al. — Thu, 08 Apr 2010 21:40:06 PDT

When identifying motor difficulties such as DCD, there is dissension as to what cut points should be used in research and intervention. These cut points are generally based on motor performance test scores and range from the 5th to the 15th percentile. The adoption of the lower point should be challenged because many children, who also have movement related psychosocial difficulties and low fitness, may not be identified. Two limitations arise from using the 5th percentile as a cut-score: a) given the multi-causal nature of DCD, research using a low cut-off might limit what we can ever know; and b) the research findings will have limited generalisability to future practice. The controversy surrounding cut points, and the heterogeneous nature of DCD, highlight the need for more data-based work to broaden our understanding of the limitations we impose by selecting a specific cut point.

Our purpose was to identify clusters based on fitness and physical self-perceptions of adolescents with extremely low to marginal motor performance scores. We looked to see whether these clusters provided support for a motor performance cut point that was 2 SD below, 1.5 SD below, 1.25 SD below or 1 SD below the mean of the MAND Neurodevelopmental Index (McCarron, 1997). The 14-year-old participants (N = 317) completed the athletic subscale of the Self-Perception Profile for Adolescents (Harter, 1988), three questions on enjoyment and ability in physical activities, and fitness measures: BMI, upper limb strength; abdominal endurance; flexibility; and PWC170.

The Impact of Sex and Motor Competence on Health Related Fitness

Beth Hands et al. — Mon, 29 Mar 2010 21:09:28 PDT

Recent evidence suggests that motor competence may be related to a number of health related fitness variables. It is probable that fitness outcomes worsen as motor incompetence increases. Measures of abdominal muscles endurance, upper and lower body muscles strength, hip flexibility, cardiovascular endurance and body composition were compared among 1535 13-year-olds who were grouped according to their level of motor competence [very low (boys = 32, girls = 30), low (boys = 151, girls = 144), average (boys = 436, girls = 446) and high (boys = 176, girls = 120)]. The groupings were based on their motor scores obtained from the MAND. Analyses of variance were conducted to explore the impact of sex and motor competence on each fitness variable. Results revealed significant main effects for motor competence and sex for abdominal muscle endurance (p< .001), leg strength (p< .001), upper body strength (p<.001), hip flexibility (p<.001) and cardiovascular endurance (p<.001). Body composition was significantly different between motor competence groups (p< .001) but not between males and females. For motor competence the differences were all in the predicted direction with the very low motor competence group having the poorer outcomes across all measures. For sex, males outperformed females in all measures except hip flexibility. There was a significant interaction effect for upper body strength [F(3, 1527) = 9.69, p = .00] and lower body strength [ F(3, 1527) = 2.91, p = .03]. For these strength variables, motor competence had a greater impact on the boys’ performance than the girls. Overall, adolescents with motor difficulties were less fit across a range of variables than their typically developing peers. As the severity of motor impairment increased performance outcomes on a number of health related fitness variables reduced. These findings confirm the impact of motor incompetence on physical health and add to the growing evidence of poorer long term health outcomes.

Psycho-Social Aspects of Low Motor Competence in Adolescents

Elizabeth Rose et al. — Mon, 29 Mar 2010 20:46:56 PDT

Researchers in social psychology and adaped physical activity place importance on developmental self esteem, proposing that level of motor competence is closely linked to perceived competence and global self worth. In this study our purpose was to examine differences in domain specific self perceptions and global self worth with adolescents who differed in level of motor competence. Participants (N=1,570, girls = 763 and boys = 803) were grouped into one of 4 groups; very low, low, average, and high motor competence using their NDI scores ontained fromperforming the motor tasks from the MAND. Participants also completed the Self Perception Profile for Adolescents that taps perceptions of: a) athletic competence; b) physical appearance; c) peer acceptance; d) close friendship; e) romantic appeal d) behavioural conduct; e) job competence; f) scholastic competence; and g) global self-worth.

The Incidence and Implications of Diagnosed Problems in Adolescents Wtih DCD

Dawne Larkin et al. — Mon, 29 Mar 2010 20:12:10 PDT

The widespread notion that many children with DCD have co-occuring problems has been linked with the notion of atypical brain development. Thus we would anticipate that more severe motor problems would be accompanied by more diagnosed problems such as language and intellectual problems. Much of the research has been done with clinical samples, here we present data from a population based sample. We explore the incidence of diagnosed problems in a large sample of adolescents with and without motor difficulties. We also address the question: do children with more severe (very low) motor difficulties have more co-occurring problems than children with mild (low) motor difficulties?

Young children’s perceived motor competence and actual motor

Fleur McIntyre et al. — Sun, 28 Mar 2010 23:51:16 PDT

This paper presents the preliminary findings from stage one of a longitudinal study. Children aged 6-8 years (N = 201) used pedometers to record daily step counts over 7 days. Motor competence was evaluated based on their performance of 4 motor skills and perceived motor competence was assessed via completion of a Self Description Questionnaire (Marsh, 1988). Significant differences in mean daily step counts were found between males (M = 14,522) and females (M = 12,272, p = .00). Significant differences for males and females were also found in total motor competency scores (males = 15.7, females = 17.6, p = .00) and between age groups (6 year olds = 15.6, 7 year olds = 17.0, 8 year olds = 17.6, p = .001). Self perceptions differed significantly between 6 and 8 year olds (p = .02), and 7 and 8 year olds (p = .01). Significant correlations were found between physical activity and motor competence for males(r = .36), but not females (r = .21) and also for 6 year olds (r = .30) and 7 year olds (r = .57). Investigating these relationships in typically developing children will provide important information for enabling a physically active lifestyle in future years.

A Day in the Life of Adolescents: Computer-based Self-report of Physical Activity and Sedentary Behaviour and Pedometer Measures of Physical Activity in 14 Year Old Boys and Girls

Helen Parker et al. — Sun, 28 Mar 2010 19:34:46 PDT

The Raine Study has been tracking the development of approximately 2860 children since in utero. At their 13th birthday assessment, 418 girls, and 384 boys completed the MARCA (Ridley, Olds, & Hill, 2006), a computer-based, self-report diary of daily activities and recorded their pedometer steps. MARCA data were coded for activity type - sedentary, including TV/video, computer and e-games, and for physical activity levels, duration, and frequency. Daily average time spent in the activity types and step counts were calculated. Pedometer step counts were significantly different between girls (M = 10,042) and boys (M = 11,572, p < .01). A low, but significant, relationship was found between step counts and MARCA daily average time for MVPA for both male and females (r = .304 and re = .354, p <, .05, respectively). Higher step counts were significantly associated with lower MARCA sedentary time for girls (r = -156, p<.01) but not boys (r=-.09). In reverse, lower pedometer counts were inversely associated with greater electronic media use for both boys and girls (r=-.237, r=-.225, respectively, p< .05). The proportion of children adhering to the physical activity and sedentary behaviour guidelines for children will be discussed.

Developmental Changes in Factors Affecting Physical Activity: a Mixed-Longitudinal Study

Fleur McIntyre et al. — Thu, 25 Mar 2010 22:10:18 PDT

Percieved motor competence and actual motor competence and physical activity was measured 4 times over 18 months in children aged 6 - 8 years (N = 201). Results from baseline and 6 month data revealed boys were more active than girls at all ages and there was no significant increase or decrease in physical activity for either gender at any age. Percieved motor competence scores for boys and girls decreased over 6 months whilst actual motor competence scores increased. Physical activity is related to actual motor competence but not perceived motor competence in this age group with a significant positive relationship between actual motor competence and physical activity emerging in older boys. These data indicate that self perceptions of competence in young boys and girls do not necessarily match development in actual motor competence. Whether such dissociation continues will be explored in later follow up at 12 and 18 months from the initial measurement point.

Are We Measuring Motor Ability?

Dawne Larkin et al. — Thu, 25 Mar 2010 20:59:29 PDT

A number of test batteries are used to identify children with motor dificulties such as dyspraxia, developmental coordination disorder (DCD) or motor learning dificulties (MLD). These batteries implicitly assume a higher order construct since they provide a composite score as an indicator of overall motor performance. In this study, we use Burton and Rodgerson’s (2001) theoretical taxonomy of motor behavior to guide the interpretation of an assessment tool. In this study we investigated the hierarchical structure of the McCarron Assessment of Neuromuscular Development (MAND) (McCarron, 1982) to ascertain the irst order factors and whether there were higher order factors. The MAND battery has 10 items measuring a range of motor skills noted below. Motor scores were obtained from a subsample of 1,619 ten-year-olds (boys = 842, girls = 777) from the longitudinal Western Australian Pregnancy Cohort (Raine) Study. Principal components analysis with Promax rotation yielded three factors with eigenvalues ≥ 1 and explained 49% of the variance. The irst 1st order factor, which we called stability, explained 26% of the variance and included one foot stand, heel-toe walk, inger-nose, rod-slide and inger tap (factor loadings .69 - .39). The second factor, called dexterity, explained 12% of the variance and comprised nut and bolt, beads on rod and beads in box (factor loadings .74 - .71). The third 1st order factor, called muscle power, explained 11% of the variance and included grip strength and standing broad jump (factor loadings .84 - .60). All three 1st order factor scores were used in the second order principal component analysis. Only one component, with an eigenvalue ≥ 1, was extracted, which explained 45% of the variance. All three 1st order factors contributed providing psychometric evidence of a higher order abstract construct. The irst order factors were consistent with movement skill foundations as represented in Burton and Rodgerson’s (2001) taxonomy, but did not support a taxonomic division into ine and gross motor skill sets. The second order factor is consistent with their general motor ability construct. In order to achieve a high score on the McCarron battery, a child had to respond to complex and varied motor task demands often in an unfamiliar environment. There is a need for further debate and research into the meaning of higher order constructs. For example, are we measuring motor ability or kinaesthetic intelligence?

Play5 Every Day: Children Taking control of Their Own Physical Activity Level

Beth Hands et al. — Thu, 25 Mar 2010 19:23:49 PDT

An internal sense of control in a particular domain such as physical activity is likely to enhance the intrinsic desire to engage in future opportunities. In this study, the ability of seven-year-old children to mange their own daily physical activity was evaluated in a randomised controlled trial involving 30 (15 experimental and 15 control) primary schools in Perth, Western Australia. The six month Play5 intervention involved a series of home and school based strategies to support children to make active choices pre, post and 6 months after the intervention. Where complete data sets were available, analyses revealed different trends for boys (experimental = 29, contol = 28) and girls (experimental = 23, control = 27). In general, males in the experimental group reduced the time spent in sedentary activities, particularly screen time whereas girls increased the time spent engaged in vigorous physical activity. These findings indicate that young children are able to choose to be less sedentary and more active even without specific reinforcement of strategies at home or school during the post-intervention phase.

Behavioural and Emotional Problems in Children with Varying Levels of Motor Learning Difficulties

Beth Hands et al. — Tue, 23 Mar 2010 00:08:32 PDT

Children with motor learning difficulties are more likely to experience behavioural and emotional problems than typically developing children, however few studies have examined whether these problems are exacerbated among children with more severe motor difficulties. This paper examines the differences in social and behavioural symptoms among 1592 ten-year-old children, with (n=226) and without (n=1366) motor learning difficulties.

Left-handedness in Boys at 10 Years of Age May Result From Maternal Preeclampsia But Not From Prenatal Ultrasound Scans

D A. Doherty et al. — Mon, 22 Mar 2010 23:25:31 PDT

Aims: Despite widespread acceptance of prenatal ultrasound scans there remain lingering uncertainties that scans may increase non-right handedness. Our aim was to investigate an association between ultrasound exposure in utero and left handedness.

Study design: Study of children at 10 years of age whose mothers had participated in a randomised controlled trial evaluating effects of multiple antenatal ultrasounds on pregnancy outcomes. Women were randomised to a protocol of 5 ultrasound scans or a single scan with further scans for clinical indications (The Raine Study, 1989 1992).

Doherty, D. A., Hands, B., Kendall, G. E., Landau, L. L., Stanley, F. J., & Newnham, J. P. (2007). Left-handedness in boys at 10 years of age may result from maternal preeclampsia but not from prenatal ultrasound scans. Early Human Development, 83, S47-S82. doi:10.1016/S0378-3782(07)70055-5

Gender Differences in Neuropsychological Functioning Among Children With Different Levels of Motor Difficulty

Dawne Larkin et al. — Mon, 22 Mar 2010 22:31:37 PDT

It is often assumed that boys and girls with more severe motor difficulties are more likely to have cerebral dysfunction and thus more problems with neuropsychological functioning. In order to explore this issue we examined the responses of a cohort of 10 year-old boys and girls with low and very low motor proficiency levels on written and oral forms of the Symbol Digit Modalities Test (SDMT). This test is used to assess neuropsychological functions including attention, impaired visual scanning, visual-perceptual ability and speed of motor processing.