Congestion pricing and active transport - evidence from five opportunities for natural experiment

Congestion pricing schemes have been implemented in cities worldwide as a means of addressing externalities associated with inefficient price signals in transport systems. Limited evidence exists however on the secondary impacts of these schemes, which may include both environmental and health benefits associated with a resultant reduction in motor vehicle usage. There is increasing recognition that transport behaviours may play a role as opportunistic population level targets to reduce physical inactivity. Yet limited evidence currently exists on the effectiveness of transport interventions, such as congestion pricing schemes, for improving physical activity levels.This study aims to examine the physical activity effects of congestion pricing, with the health benefits of physical activity well established. Congestion pricing schemes implemented internationally were considered as 'natural experiments' and evidence of modal shift from vehicle to active forms of transport or physical activity effect was reviewed. Twelve studies were included from a search of peer-reviewed and 'grey' literature, with overall evidence for a physical activity or modal shift effect considered weak. The quality of the available evidence was also considered to be low.This is not to say that congestion pricing schemes may not have important secondary physical activity related health benefits. Instead, this review highlights the paucity of evidence that has been collected from real-world implementation of congestion pricing schemes. Given the growing recognition of the importance of distal mediators and determinants of health and the need for an 'all-of-government' approach more and better quality evidence of effectiveness of transport interventions for a broad range of outcomes, including health, is required. Significant barriers to the collection of such evidence exist, with strategies for overcoming some of these barriers identified. Only with a better understanding of the full range of potential health impacts can transport policy be fully utilised as a tool for population health.

A systematic review of economic analyses of active transport interventions that include physical activity benefits

Physical inactivity is one of the leading causes for the growing prevalence of non-communicable diseases worldwide and there is a need for more evidence on the effectiveness and cost-effectiveness of interventions that aim to increase physical activity at the population level. This study aimed to update a systematic review published in 2008 by searching peer-reviewed and unpublished literature of economic evaluations of transport interventions that incorporate the health related effects of physical activity. Our analysis of methods for the inclusion of physical activity related health effects into transport appraisal over time demonstrates that methodological progress has been made. Thirty-six studies were included, reflecting an increasing recognition of the importance of incorporating these health effects into transport appraisal. However, significant methodological challenges in the incorporation of wider health benefits into transport appraisal still exist. The inclusion of physical activity related health effects is currently limited by paucity of evidence on morbidity effects and of more rigorous evidence on the effectiveness of interventions. Significant scope exists for better quality and more transparent reporting. A more consistent approach to the inclusion of benefits and disbenefits would reinforce the synergies between the health, environmental, transport and other sectors. From a transport sector perspective the inclusion of physical activity related health benefits positively impacts cost effectiveness, with the potential to contribute to a more efficient allocation of scarce resources based on a more comprehensive range of merits. From a public health perspective the inclusion of physical activity related health benefits may result in the funding of more interventions that promote active transport, with the potential to improve population levels of physical activity and to reduce prevalence of physical activity related diseases.

Personal, family, social, and environmental correlates of active commuting to school

Background: Active commuting to school may be an important opportunity for children to accumulate adequate physical activity for improved cardiovascular risk factors, enhanced bone health, and psychosocial well-being. The purpose of this study was to examine personal, family, social, and environmental correlates of active commuting to school among children. Methods: Cross-sectional study of 235 children aged 5 to 6 years and 677 children aged 10 to 12 years from 19 elementary schools in Melbourne, Australia. Self-administered questionnaires were completed by parents, and the older children. The shortest possible routes to school were examined using a geographic information system. Results: Among both age groups, negative correlates of active commuting to school included parental perception of few other children in the neighborhood and no lights or crossings for their child to use, and an objectively assessed busy road barrier en route to school. In younger children, an objectively assessed steep incline en route to school was negatively associated with walking or cycling to school. Good connectivity en route to school was negatively associated with walking or cycling to school among older children. Among both age groups, children were more likely to actively commute to school if their route was <800 meters. There were no associations with perceived energy levels or enjoyment of physical activity, weight status, or family factors. Conclusions: For children, creating child-friendly communities and providing skills to safely negotiate the environment may be important. Environmental correlates of active transport in children and adults may differ and warrant further investigation.

Motivational readiness for active commuting by university students : incentives and barriers

Issue addressed: Walking for transport can contribute significantly to health enhancing physical activity. We examined the associations of stages of motivational readiness for active transport with perceived barriers and incentives to walking to and from university among students. Methods: Mail-back surveys were completed by 781 students in a regional university in southeast Queensland. They identified one of eight options on motivational readiness for active commuting, which were then classified as: pre-contemplation; contemplation-preparation; or, action-maintenance. Open-ended questions were used to identify relevant barriers and incentives. Logistic regressions were used to examine the barriers and incentives that distinguished between those at different stages of motivational readiness. Results: Barriers most frequently reported were long travel distances, inconvenience and time constraints. Incentives most frequently reported were shorter travel distance, having more time, supportive infrastructure and better security. Those not considering active commuting (pre-contemplation) were significantly more likely to report shorter travel distance as an incentive compared to those in contemplation-preparation. Those in contemplation-preparation were significantly more likely to report lack of motivation, inadequate infrastructure, shorter travel distance and inconvenience as barriers; and, having more time, supportive infrastructure, social support and incentive programs as encouragement. Conclusions: Different barriers and incentives to walking to or from university exist for students in the different stages of motivational readiness for active commuting. Interventions targeted specifically to stage of motivational readiness may be potentially helpful in increasing activity levels, through active transport.

Gender differences in personal, social and environmental influences on active travel to and from school for Australian adolescents

Active travel (walking or cycling for transport) is an important contributor to adolescents overall physical activity (PA). This study examines associations between personal, social and environmental variables and active travel to and from school using data from a large observational study to examine active travel in 2961 year 6 and 8 students (48.7% male), aged 10–14 years (M = 11.4, SD = 0.8 yrs) from 231 schools. Participants completed an on-line survey and all reported living within 2 km of school. Data collected included mode of travel to and from school, self-reported health, and PA variables. Social environmental variables included having playgrounds, parks or gyms close by, feeling safe to walk alone, barriers to walking in the neighbourhood (e.g. traffic, no footpaths), peer and family support for PA, existence of sports teams/scout groups, community disorder and perceived neighbourhood safety. Results showed that while more girls (44.3%) than boys (37.4%) walked to school, lower proportions rode bikes (8.3% vs 22.4%) and hence fewer were active travellers overall. Logistic regression models, adjusted for age, location and socio-economic status were conducted for active travel to/from school, separately for boys and girls. Predictors for boys and girls being ‘active travellers’ to/from school included recreational facilities close to home, higher perceived safety of the neighbourhood and higher community disorder. For boys, social support from friends, scout groups available and higher enjoyment of physical activity was also important. These findings suggest areas for future research and may be used to guide strategies to increase active travel to and from school.

Gender differences in recreational and transport cycling : a cross-sectional mixed-methods comparison of cycling patterns, motivators, and constraints

Background
Gender differences in cycling are well-documented. However, most analyses of gender differences make broad comparisons, with few studies modeling male and female cycling patterns separately for recreational and transport cycling. This modeling is important, in order to improve our efforts to promote cycling to women and men in countries like Australia with low rates of transport cycling. The main aim of this study was to examine gender differences in cycling patterns and in motivators and constraints to cycling, separately for recreational and transport cycling.

Methods
Adult members of a Queensland, Australia, community bicycling organization completed an online survey about their cycling patterns; cycling purposes; and personal, social and perceived environmental motivators and constraints (47% response rate). Closed and open-end questions were completed. Using the quantitative data, multivariable linear, logistic and ordinal regression models were used to examine associations between gender and cycling patterns, motivators and constraints. The qualitative data were thematically analyzed to expand upon the quantitative findings.

Results
In this sample of 1862 bicyclists, men were more likely than women to cycle for recreation and for transport, and they cycled for longer. Most transport cycling was for commuting, with men more likely than women to commute by bicycle. Men were more likely to cycle on-road, and women off-road. However, most men and women did not prefer to cycle on-road without designed bicycle lanes, and qualitative data indicated a strong preference by men and women for bicycle-only off-road paths. Both genders reported personal factors (health and enjoyment related) as motivators for cycling, although women were more likely to agree that other personal, social and environmental factors were also motivating. The main constraints for both genders and both cycling purposes were perceived environmental factors related to traffic conditions, motorist aggression and safety. Women, however, reported more constraints, and were more likely to report as constraints other environmental factors and personal factors.

Conclusion
Differences found in men’s and women’s cycling patterns, motivators and constraints should be considered in efforts to promote cycling, particularly in efforts to increase cycling for transport.

Incidental physical activity in Melbourne, Australia: health and economic impacts of mode of transport and suburban location.

Using the known health impacts of physical activity (PA), levels of incidental PA in Melbourne were analysed, and after determining key behavioural associations, economic modelling estimated potential long-term health and economic benefits of changes in active transport (AT) patterns.

Healthy revolutions: promoting cycling among women

Issue addressed: Australian women's participation in cycling for transport and recreation is approximately half that of men. These gender differences do not occur in several western European countries. Research is required to investigate the individual, social and environmental determinants of Australian women's participation in cycling for transport and recreation.

Discussion: Few studies have systematically investigated women's perceptions and experiences of cycling and little is known about what motivates and sustains their involvement. Preliminary indications are that, for women, there may be an interest in and capacity to participate in cycling that is not being translated into practice. Safety concerns appear to be a significant deterrent to women cycling. Safety factors have a differential impact on women as they are generally more risk averse than men. Quantitative risk assessments suggest that the risk of injury associated with cycling is small and that the health benefits outweigh the health costs. Cycling promotion campaigns may achieve greater success with women if they enable women to experience cycling in an environment that both is, and is perceived to be, safe and supportive.

Conclusions: Research is needed to determine what strategies are likely to be most effective in promoting cycling among Australian women, as a basis for developing programs, policies and facilities to support women's participation in cycling.

Trends in children`s physical activity and weight status in high and low socio-economic status areas of Melbourne, Victoria, 1985-2001

Objective:
To examine trends in active transport to and from school, in school sport and physical education (PE), and in weight status among children from high and low socio-economic status (SES) areas in Melbourne, Victoria, between 1985 and 2001.

Methods:
Cross-sectional survey data and measured height and weight from 1985 (n=557) and 2001 (n=926) were compared for children aged between 9–13 years within high and low SES areas.

Results:
From 1985 to 2001, the frequency of walking to or from school declined (4.38±4.3 vs. 3.61 ± 3.8 trips/wk, p<0.001), cycling to or from school also declined (1.22±2.9 vs. 0.36±1.5 trips/wk, p<0.001), and the frequency of PE lessons declined (1.64±1.1 vs. 1.18±0.9 lessons/wk, p<0.001). However, the frequency of school sport increased (0.9±1.22 vs. 1.24±0.8 sessions/wk, p<0.001). In 1985, 11.7% of children were overweight or obese compared with 28.7% in 2001 (p<0.001). Apart from walking to school and school sport, there were greater relative declines in cycling to school and PE, and increases in overweight and obesity among children attending schools in low SES areas compared with those attending schools in high SES areas.

Conclusions:
Declines in active school transport and PE have occurred at the same time as increases in overweight and obesity among Australian children.

Implications:
Promoting active school transport and maintaining school sport and PE should be important public health priorities in Australia. Current inequities in school sport and PE and in prevalence of overweight and obesity by area-level SES also need to be addressed.

Effect of dietary fatty acids on the intestinal permeability of marker drug compounds in excised rat jejunum

The aim of this study was to explore the effects of diets containing saturated fatty acids (SFA), monounsaturated fatty acids (MUFA), and ω-3 and ω-6 polyunsaturated fatty acids (ω-3 and ω-6 PUFA, respectively) on the passive and active transport properties of rat jejunum using marker compounds. Rats were fed diets supplemented with 18.4% (w/w) lipid (4 groups) or standard rat chow (1 group) for a period of 30 days. At the end of the dietary period, mucosal scrapings were taken for the determination of membrane phospholipids, and the apparent jejunal permeability of radiolabelled marker compounds was determined using modified Ussing chambers. Changes in the phospholipid content of the brush border membrane reflected the different lipid content of the diets. The passive paracellular permeability of mannitol was not significantly affected by the fatty acid composition of the diet, although there was a trend toward decreased mannitol permeability in the rats fed both the ω-3 and ω-6 PUFA diets. In comparison, the transcellular diffusion of diazepam was reduced by 20% (P < 0.05) in rats fed diets supplemented with ω-3 and ω-6 PUFA. In the lipid-fed rats, the serosal to mucosal flux of digoxin, an intestinal P-glycoprotein substrate, was reduced by 20% (P < 0.05) relative to the chow-fed group, however there were no significant differences between the different lipid groups. The active absorption of D-glucose via the Na+-dependent transport pathway was highest in the SFA, MUFA and PUFA ω-3 dietary groups, intermediate in the low-fat chow group and lowest in the PUFA ω-6 group, and was positively correlated with short-circuit current. These studies indicate that dietary fatty acid changes can result in moderate changes to the active and passive transport properties of excised rat jejunum.

Playing it safe : the influence of neighbourhood safety on children's physical activity − A review

Compared with previous generations, children spend less time playing outdoors and have lower participation rates in active transport. Many studies have identified lack of neighbourhood safety as a potential barrier to children's physical activity. This review describes concerns regarding ‘stranger danger’ and road safety, and discusses empirical studies that examine associations between neighbourhood safety and physical activity among youth. Variability of perceptions of safety between parents and youth are examined; ‘social traps’ are identified; and physical/social environmental interventions aimed at improving neighbourhood safety are discussed. A research agenda is suggested for further study of perceived and objective measures of neighbourhood safety and their associations with children's physical activity.

Neighborhood road environments and physical activity among youth : the CLAN Study

We examined associations between objective measures of the local road environment and physical activity (including active transport) among youth. There is little empirical evidence of the impact of the road environment on physical activity among children/adolescents in their neighborhoods. Most recent studies have examined perceptions rather than objective measures of the road environment. This was a cross-sectional study of children aged 8–9 years (n = 188) and adolescents aged 13–15 years (n  = 346) who were participants in the 3-year follow-up of the Children Living in Active Neighborhoods (CLAN) longitudinal study in Melbourne, Australia. At baseline (2001), they were recruited from 19 state primary schools in areas of varying socioeconomic status across Melbourne. Habitual walking/cycling to local destinations was parent-reported for children and self-reported for adolescents, while moderate-to-vigorous physical activity (MVPA) outside school hours was recorded using accelerometers. Road environment features in each participant’s neighborhood (area of radius 800 m around the home) were measured objectively using a geographical information system. Regression analyses found no associations between road environment variables and children’s likelihood of making at least seven walking/cycling trips per week to neighborhood destinations. Adolescent girls residing in neighborhoods with two to three traffic/pedestrian lights were more likely to make seven or more walking/cycling trips per week as those whose neighborhoods had fewer traffic lights (OR: 2.7; 95% CI: 1.2–6.2). For adolescent boys, residing on a cul-de-sac, compared with a through road, was associated with increases in MVPA of 9 min after school, 5 min in the evenings, and 22 min on weekend days. Speed humps were positively associated with adolescent boys’ MVPA during evenings. The road environment influences physical activity among youth in different ways, according to age group, sex and type of physical activity.

How do school day activity patterns differ with age and gender across adolescence?

Purpose
A knowledge of how young people use their time could be instrumental in informing health interventions, modeling consumer behaviors, and planning service delivery. The aim of the present study was to describe age- and gender-related patterns in the self-reported use of time on school days in a large sample of Australian children and adolescents aged between 10 and 18 years.

Methods
A single, detailed use-of-time diary for a school day was collected from 6024 Australians aged 10–18 from several state and regional surveys conducted in the states of South Australia (SA) and Victoria between 2001 and 2006. Time–use profiles were analyzed for a range of active and sedentary state behaviors.

Results
Boys reported higher physical activity levels (PALs), moderate-to-vigorous physical activity (MVPA), and sports than girls. There were no differences in free play, and girls used more active transport. All activity-related variables decreased with age, except active transport, which peaked at 14–15 years. Boys exhibited higher levels of screen time, whereas girls had higher levels of passive transport. Screen time and its components (television, videogames, and computer use) peaked in the peripubertal years.

Conclusion
Age- and gender-related patterns of time use vary greatly within adolescence. This may reflect a mix of biological and social factors.

Associations between neighbourhood safety and physical activity among youth

This thesis examined how perceptions of neighbourhood safety and objective measures of the local road environment were related to physical activity among youth. Results demonstrated that neighbourhoods with walking tracks and traffic-calming measures promote active transport (walking/cycling) and may help stem age-related declines in physical activity among children and adolescents.