Influences on preschool children's physical activity

This study explored mothers' perceptions of influences on preschoolers' physical activity. Six semistructured focus groups with 23 mothers were conducted across a range of socioeconomic position locations. Mothers identified 4 key areas of influence: child fundamentals (eg, sex, personality), parent power (eg, rules, support), people to share with (eg, peers, adults), and places and things (eg, physical environments, toys). No substantial differences in themes were identified among socioeconomic position groups. Influences on preschoolers' physical activity are multidimensional, multifactorial, and support the use of ecological models to conceptualize and understand the influencing factors. Associations among factors influencing preschoolers' physical activity should be further investigated through quantitative research.

Lower levels of physical activity in childhood associated with adult depression

Emerging evidence indicates that early life exposures influence adult health outcomes and there is cause to hypothesise a role for physical activity (PA) in childhood as a protective factor in adult depression. This study aimed to investigate the association between self-reported levels of PA in childhood and self-reported depressive illness. Lifetime depression and levels of physical activity (low/high) in childhood (<15 yr) were ascertained by self-report in 2152 adults (20–97 yr) participating in an ongoing epidemiological study in south-eastern Australia. Data were collected between 2000 and 2006. In this sample, 141 women (18.9%) and 169 men (12.0%) reported ever having a depressive episode. Low PA in childhood was associated with an increased risk of reporting depression in adulthood (OR = 1.70, 95%CI = 1.32–2.17, p < 0.001). Adjustment for age, gender and adult PA attenuated the relationship somewhat (OR = 1.35, 95%CI = 1.01–1.78, p = 0.04), however further adjustment for SES or country of birth did not affect this relationship. In this community-based study, lower levels of self-reported PA in childhood were associated with a 35% increase in odds for self-reported depression in adulthood. These results are consistent with the hypothesis that lower levels of PA in childhood may be a risk factor for adult depression.

Is healthy behavior contagious : associations of social norms with physical activity and healthy eating

Background
Social norms are theoretically hypothesized to influence health-related behaviors such as physical activity and eating behaviors. However, empirical evidence relating social norms to these behaviors, independently of other more commonly-investigated social constructs such as social support, is scarce and findings equivocal, perhaps due to limitations in the ways in which social norms have been conceptualized and assessed. This study investigated associations between clearly-defined social norms and a range of physical activity and eating behaviors amongst women, adjusting for the effects of social support.

Methods
Self-report survey data about particular physical activity (leisure-time moderate-vigorous activity; volitional walking; cycling for transport) and eating behaviors (fast food, soft drink and fruit and vegetable consumption), and social norms and support for these, were provided by 3,610 women aged 18-46 years living in socioeconomically disadvantaged neighborhoods in Victoria, Australia.

Results
Results of regression analyses showed that social norms for physical activity and eating behaviors predicted these respective behaviors relatively consistently; these associations generally remained significant after adjustment for social support.

Conclusions
Acknowledging the cross-sectional study design, these data confirm theoretical accounts of the importance of social norms for physical activity and eating behaviors, and suggest that this is independent from social support. Intervention strategies aimed at promoting physical activity and healthy eating could incorporate strategies aimed at modifying social norms relating to these behaviors.

The association between physical activity and depression among young women

Young women experiencing depressive symptoms were shown to have different constraints to being active compared to young women without depressive symptoms, such as lower motivation and lower confidence in their ability to be active. Physical activity promotion initiatives may benefit from individually-tailored, multi-component programs rather than a 'one-fits-all', single-arm approach

Describing and understanding physical activity in desk-based work settings

This thesis investigated the physical activity behaviours of employees who commonly sit for work tasks. Specifically, this PhD explored the key influences on light-intensity physical activity during work hours and issues associated with subjectively assessing this behaviour. Overall, this PhD provided insights into a novel approach to address the important public health issue of physical inactivity.

Seasonal reduction in physical activity and flow-mediated dilation in children

Purpose: Cardiovascular disease is a process that has its origins in childhood. Endothelial dysfunction is the earliest detectable manifestation of cardiovascular disease. This study aimed to assess the impact of seasonal changes in physical activity (PA) and body composition on conduit artery endothelial function in children.

Method: We studied 116 children (70 girls aged 10.7 ± 0.3 yr and 46 boys aged 10.7 ± 0.3 yr) on two occasions; in the northern summer (June) and late autumn (November). We assessed flow-mediated dilation (FMD) using high-resolution Doppler ultrasound. Body composition was measured by dual-energy x-ray absorptiometry. PA was assessed using accelerometry.

Results: FMD (10.0% ± 4.3% to 7.9% ± 3.9%, P < 0.001) and PA (94.1 ± 34.8 to 77.8 ± 33.7 min·d-1, P < 0.01) decreased, while percentage body fat increased (27.6% ± 6.8% to 28.0% ± 6.6%, P < 0.001) between summer and autumn. Decreases in FMD correlated with decreases in high-intensity PA (r = 0.23, P = 0.04), and change in high-intensity PA was the only predictor of change in FMD. No relationships were evident between changes in body composition and FMD.

Conclusions: Vascular function decreased between summer and autumn in this cohort. There were no relationships between change in FMD and changes in body composition or low/moderate-intensity PA. The associations between FMD and high-intensity PA suggests that future interventions should encourage this form of behavior, particularly at the times of year associated with lower PA.

Obesity prevention in the family day care setting : impact of the romp & chomp intervention on opportunities for children's physical activity and healthy eating

Background The Romp & Chomp intervention reduced the prevalence of overweight/obesity in pre-school children in Geelong, Victoria, Australia through an intervention promoting healthy eating and active play in early childhood settings. This study aims to determine if the intervention successfully created more health promoting family day care (FDC) environments.
Methods The evaluation had a cross-sectional, quasi-experimental design with the intervention FDC service in Geelong and a comparison sample from 17 FDC services across Victoria. A 45-item questionnaire capturing nutrition- and physical activity-related aspects of the policy, socio-cultural and physical environments of the FDC service was completed by FDC care providers (in 2008) in the intervention (n = 28) and comparison (n = 223) samples.
Results Select results showed intervention children spent less time in screen-based activities (P = 0.03), organized active play (P < 0.001) and free inside play (P = 0.03) than comparison children. There were more rules related to healthy eating (P < 0.001), more care provider practices that supported children’s positive meal experiences (P < 0.001), fewer unhealthy food items allowed (P = 0.05), higher odds of staff being trained in nutrition (P = 0.04) and physical activity (P < 0.001), lower odds of having set minimum times for outside (P < 0.001) and organized (P = 0.01) active play, and of rewarding children with food (P < 0.001).
Conclusions Romp & Chomp improved the FDC service to one that discourages sedentary behaviours and promotes opportunities for children to eat nutritious foods. Ongoing investment to increase children’s physical activity within the setting and improving the capacity and health literacy of care providers is required to extend and sustain the improvements.

A pilot program of physical activity promotion among clients receiving home and community care

Three Victorian local governments cooperated in a pilot study of physical activity promotion as part of home and community care (HACC) service delivery. Thirty-one people receiving HACC volunteered to participate, including completing the Transtheoretical Stages of Change Exercise Questionnaire and the short-form Stanford Health Assessment Questionnaire (HAQ) just before and at 3 months and 6 months after starting regular self-selected physical activity. Twenty-one participants returned questionnaires at 3 months, and 17 participants returned questionnaires at 6 months. Data were analysed using paired t tests and effect sizes were calculated as mean differences. At 3 months, mean improvements were identified on 6 of the 8 HAQDI (disability index) subscales, and in the overall HAQ-DI score. Improvement in dressing and grooming was preserved at 6 months. At either 3 or 6 months, improvements in dressing and grooming, reach, hygiene, and daily activities, and overall HAQ-DI score exceeded the minimum clinically important difference. No improvements were statistically significant, as is likely in a pilot study with a small sample, however, these results suggest that even very small increases in physical activity may afford clinically meaningful improvements in some areas of physical function required for independent living.

Social ideological influences on food consumption, physical activity and BMI

We investigated relationships between ideological beliefs (i.e., diaphanous body image and environmental concerns), food attitudes, evening meal patterns, physical activity, and Body Mass Index (BMI). A behavioural model was hypothesized based on the Theory of Reasoned Action. A survey was conducted among shoppers aged 40–70 years at Eastland Shopping Centre, Melbourne, Australia. The hypothesized model was tested among female baby boomers (n = 547) for younger (n = 245) and older (n = 302) age groups using structural equation modeling. Findings showed that diaphanous body image had a direct and positive influence on negative food attitudes, which is likely to lead to higher BMI for both age groups. Body image beliefs were positively related to physical activity only for women aged 56–70 years. In contrast, among women aged 40–55 years, strong pro-environmental concerns suggested less consumption of both healthy (e.g., fruit and vegetables) and unhealthy (e.g., sugar and fats) foods. Moreover, strong pro-animal concerns resulted in higher BMI for the younger women. As expected, increased physical activity negatively influenced BMI. Importantly, the associations between ideological beliefs, attitudes, evening meal patterns, and BMI differed between younger and older female baby boomers.

Effects of a daily school based physical activity intervention program on muscle development in prepubertal girls

This 12-month prospective controlled intervention evaluated the effect of a general school based physical activity program on muscle strength, physical performance and body composition in prepubertal girls. Fifty-three girls aged 7–9 years involved in a school based exercise program [40 min/day of general physical activity per school day (200 min/week)] were compared with 50 age-matched girls who participated in the general Swedish physical education curriculum (mean 60 min/week). Body composition (DXA), isokinetic peak torque (PT) of the knee extensors and flexors at 60 and 180°/s, and vertical jump height (VJH) were assessed at baseline and 12 months. The annual gain in weight was similar between the groups, but there was a greater increase in total body and regional lean mass (P < 0.05) and fat mass (P < 0.01) in the exercise group. Mean gains in knee extensor PT at 60 and 180°/s were 7.0–7.6% greater in the exercise group (P ranging <0.05–<0.001). No significant differences were detected in VJH. In conclusion, increasing school based physical education to at least 3 h/week provides a feasible strategy to enhance the development of muscle strength and lean mass in prepubertal girls.