Biochemical Changes in Liver and Blood During Liver Fattening in Rats

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Public health approaches to measurement, surveillance and the promotion of walking among Australian adults

The aim of this thesis is to demonstrate the importance of walking to public health. The first part is characterized by epidemiological research. First, a typology for the measurement of walking is developed. A systematic review is conducted of observational studies to determine the health benefits of walking in its own right. Studies consistently confirm that 30 minutes walking on most days of the week is sufficient to reduce the risk of cardiovascular diseases and non-communicable disease risk. Then, a series of epidemiological analyses describes the prevalence and correlates of walking, using multiple health and non-health surveillance data sets. Surveillance data indicate that the prevalence of walking at the above recommended levels is low across all domains. Between 1991 and 2001 an increase in walking occurred, and was the main contributor to reductions in leisure time physical inactivity; however, the proportion of the population who achieved the recommended amount of physical activity by walking did not change in leisure and transport domains. The next part of the thesis is characterized by health promotion research examining the impact of three population-based approaches to increasing walking among Australian adults. The first was an evaluation of a conversion of rail to trail, as an environmental change intervention; the second was a mass media campaign promoting walking to work, and the third was a targeted print media walking program. Providing environmental supports with minimal promotion had no effect on walking. A nation-wide mass media campaign promoting walking to work increased walking and other moderate intensity physical activity, but process evaluation indicated other promotional efforts contributed as well. The targeted print media randomised trial had the greatest effect on walking, but the increases were not greater than spontaneous change in the control. Increases in total physical activity were achieved only when the intervention was supplemented by the use of a pedometer. The expectation that broader approaches to the promotion of walking will bring about changes at the population level, were not corroborated by these case studies. There is a need for enhancement of walking-specific interventions to influence total PA at the population levels

Patterns of walking for transport and exercise: a novel application of time use data

BACKGROUND: Walking for exercise is a purposeful or structured activity that can be captured relatively easily in surveys focused on leisure time activity. In contrast, walking for transport is an incidental activity that is likely to be missed using these same assessment approaches. Therefore, the purpose of this analysis was to utilize 1997 Australian Bureau of Statistics (ABS) Time Use Survey diary data to describe nationally representative patterns of walking for transport and for exercise. METHODS: Household members ≥ 15 years of age were recruited from over 4,550 randomly selected private dwellings in Australia. Time use diaries were collected for two designated days during all four seasons over the calendar year. 3,471 males and 3,776 females (94% household response rate and 84% person response rate) provided 14,315 diary days of data. The raw diary data were coded and summarized into bouts and minutes that included walking for transport and for exercise. RESULTS: Walking for transport was indicated on a higher proportion of days compared to walking for exercise (20 vs. 9%). Based on participant sub-samples ('doers'; those actually performing the activity) walking for transport was performed over 2.3 ± 1.4 bouts/day (12.5 minutes/bout) for a total of ≈28 mins/day and walking for exercise over 1.2 ± 0.5 bouts/day (47 minutes/bout) for a total of ≈56 mins/day. CONCLUSION: Although walking for transport is typically undertaken in multiple brief bouts, accumulated durations approximate public health guidelines for those who report any walking for transport

Time spent playing outdoors after school and its relationship with independent mobility: a cross-sectional survey of children aged 10–12 years in Sydney, Australia

<p>Abstract</p> <p>Background</p> <p>Time spent outdoors is positively associated with physical activity and has been suggested as a proxy for physical activity of children. The role of children's independence in physical activity and time spent outdoors is less understood. This study aimed to assess how much time children spent playing outdoors after school, and to explore the relationship between outdoor play and independence among children aged 10–12 years.</p> <p>Method</p> <p>Children recorded how much time they spent playing outdoors or watching TV/videos or playing computer games after school using a five-day diary, and also reported whether they were allowed to walk on their own in their neighbourhood as an indicator of their independent mobility. Parents were surveyed on family demographics and perception of neighbourhood safety. The surveys were conducted in late 2006 as part of the Central Sydney Walk to School program which involved 1975 children and their parents from 24 primary schools. Factors associated with time spent playing outdoors were determined by logistic regression modelling.</p> <p>Results</p> <p>Thirty-seven per cent of children spent less than half an hour a day playing outdoors after school, and 43% spent more than 2 hours a day watching TV, videos or playing computer games. Forty-eight per cent of children were allowed to walk on their own near where they lived. Children's independent mobility was significantly associated with outdoor play after adjusting for other confounders. Compared with those who were never allowed to walk on their own near where they lived, students who were allowed to walk on their own were significantly more likely to spend more than half an hour a day playing outdoors after school with an adjusted odds ratio of 2.6, 95% CI 1.84–3.58, P < 0.001.</p> <p>Conclusion</p> <p>The findings that a significant proportion of children spend less than half an hour a day playing outdoors after school and have excessive screen time have important implications for physical activity promotion and obesity prevention. The study also suggests that children's independent mobility should be considered in research and evaluation into children's play and physical activity. Environments that promote greater independent mobility in children may increase their physical activity levels and hence reduce their risk of overweight/obesity.</p

Rural-to-urban migration, socio-economic status and cardiovascular diseases risk factors among Bangladeshi adults : a nationwide population based survey

Background: Rural-to-urban migration is one of the key drivers of urbanization in Bangladesh and may impact on cardiovascular diseases (CVD) risk due to lifestyle changes. This study examined whether CVD risk factors were associated with migration to and duration of urban life, considering socio-economic indicators. Methods: A total of 27,792 participants (18–59 years) from the 2006 Bangladesh cross-sectional Urban Health Survey were included in the analyses of whom 14,167 (M: 7,278; W: 6,889) were non-migrant urban residents and 13,625 (M: 6,413; W: 7,212) were rural-to-urban migrants. Gender-specific prevalence of CVD risk factors were estimated for urban and migrant groups. Multivariate logistic regression models were used to test the association between each CVD risk by education and wealth within each study group and their possible effect modification. An analysis on the rural-to-urban migrant subgroup only was conducted to examine the association between each CVD risk factor and length of urban stay adjusted for demographic and socio-economic indicators. Results: Compared to urban residents, migrants had significantly lower prevalence of overweight/obesity for both genders. Hypertension was higher among urban women while alcohol/illicit drug use was higher among urban men. Mental health disorders were higher among migrants than urban residents for both genders and no difference were noted for diabetes or cigarette smoking prevalence. In both study groups and genders, the risk of overweight/obesity, hypertension and diabetes increased with increasing education and wealth whereas for mental health disorders, alcohol/illicit drug use, cigarette and bidi smoking the reverse was found. Differences in BMI between migrant and urban women were attenuated with increased education levels (p = 0.014 for interaction). Consistent increasing pattern of risk was observed with longer duration of urban stay; in migrant men for obesity (OR = 1.67), smoking (OR = 1.67) and alcohol/illicit drug use (OR = 2.86), and for obesity and mental health disorder among migrant women. Conclusions: Migrants had high proportion of CVD risk factors which were influenced by education, wealth and duration of urban stay

Occupational risk of overweight and obesity: an analysis of the Australian Health Survey

<p>Abstract</p> <p>Background</p> <p>Adults spend about one third of their day at work and occupation may be a risk factor for obesity because of associated socioeconomic and behavioral factors such as physical activity and sedentary time. The aim of this study was to examine body mass index (BMI) and prevalence of overweight and obesity by occupation and explore the contributions of socioeconomic factors and lifestyle behaviors (including leisure time and commuting physical activity, diet, smoking, and alcohol) to occupational risk.</p> <p>Methods</p> <p>Secondary analyses of the National Health Survey in Australia (2005) were conducted for working age adults (20 to 64 years). Linear and logistic regression models using BMI as either dichotomous or continuous response were computed for occupation type. Model 1 was age-adjusted, Model 2 adjusted for age and socioeconomic variables and Model 3 adjusted for age, socioeconomic variables and lifestyle behaviours. All models were stratified by gender.</p> <p>Results</p> <p>Age-adjusted data indicated that men in associate professional (OR 1.34, 95% CI 1.10-1.63) and intermediate production and transport (OR 1.24 95% CI 1.03-1.50) occupations had a higher risk of BMI ≥ 25 kg/m²than those without occupation, and women in professional (OR 0.71, 95% CI 0.61-0.82), management (OR 0.72, 95% CI 0.56-0.92) and advanced clerical and service occupations (OR 0.73 95% CI 0.58-0.93) had a lower risk. After adjustment for socioeconomic factors no occupational group had an increased risk but for males, professionals, tradesmen, laborers and elementary clerical workers had a lower risk as did female associate professionals and intermediate clerical workers. Adjustment for lifestyle factors explained the lower risk in the female professional and associate professionals but failed to account for the lower odds ratios in the other occupations.</p> <p>Conclusions</p> <p>The pattern of overweight and obesity among occupations differs by gender. Healthy lifestyle behaviors appear to protect females in professional and associate professional occupations from overweight. For high-risk occupations lifestyle modification could be included in workplace health promotion programs. Further investigation of gender-specific occupational behaviors and additional lifestyle behaviors to those assessed in the current Australian Health Survey, is indicated.</p

Cultural participation and all-cause mortality, with possible gender differences: an 8-year follow-up in the HUNT Study, Norway

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Trends in Australian children traveling to school 1971–2003: Burning petrol or carbohydrates?

Objective. To determine how Australian children traveled to and from school between 1971 and 2003. Methods. The 1971 (n=4284), 1981 (n=4936), 1991 (n=662) and 1999–2003 (n=816) Household Travel Surveys from the New South Wales Government Department of Planning were used to determine the mode of transport kids (5–14 years) took to and from school in the area of Sydney (Australia). Results. The results showed that the percentage of children aged 5–9 that walked to school was 57.7, 44.5, 35.3 and 25.5 in 1971, 1981, 1991 and 1999–2003, respectively. The percentage of children aged 5–9 that were driven to school by car in the four surveys was 22.8, 37.3, 53.9 and 66.6, respectively. The results for children aged 10–14 were similar, walking decreased from 44.2% to 21.1% and car use increased from 12.2% to 47.8% over the study period. Similar results were found for travel from school and there were no major differences between boys and girls. Conclusion. Between 1971 and 2003, Australian children's mode of travel to and from school has markedly shifted from active (walking) to inactive (car) modes

Cognitive benefits of social dancing and walking in old age: the Dancing Mind randomized controlled trial

Background: A physically active lifestyle has the potential to prevent cognitive decline and dementia, yet the optimal type of physical activity/exercise remains unclear. Dance is of special interest as it complex sensorimotor rhythmic activity with additional cognitive, social, and affective dimensions. Objectives: To determine whether dance benefits executive function more than walking, an activity that is simple and functional. Methods: Two-arm randomized controlled trial among community-dwelling older adults. The intervention group received 1 h of ballroom dancing twice weekly over 8 months (~69 sessions) in local community dance studios. The control group received a combination of a home walking program with a pedometer and optional biweekly group-based walking in local community park to facilitate socialization. Main outcomes: Executive function tests: processing speed and task shift by the Trail Making Tests, response inhibition by the Stroop Color-Word Test, working memory by the Digit Span Backwards test, immediate and delayed verbal recall by the Rey Auditory Verbal Learning Test, and visuospatial recall by the Brief Visuospatial Memory Test (BVST). Results: One hundred and fifteen adults (mean 69.5 years, SD 6.4) completed baseline and delayed baseline (3 weeks apart) before being randomized to either dance (n = 60) or walking (n = 55). Of those randomized, 79 (68%) completed the follow-up measurements (32 weeks from baseline). In the dance group only, “non-completers” had significantly lower baseline scores on all executive function tests than those who completed the full program. Intention-to-treat analyses showed no group effect. In a random effects model including participants who completed all measurements, adjusted for baseline score and covariates (age, education, estimated verbal intelligence, and community), a between-group effect in favor of dance was noted only for BVST total learning (Cohen’s D Effect size 0.29, p = 0.07) and delayed recall (Cohen’s D Effect size = 0.34, p = 0.06). Conclusion: The superior potential of dance over walking on executive functions of cognitively healthy and active older adults was not supported. Dance improved one of the cognitive domains (spatial memory) important for learning dance. Controlled trials targeting inactive older adults and of a higher dose may produce stronger effects, particularly for novice dancers. Trial registration: Australian and New Zealand Clinical Trials Register (ACTRN12613000782730)