active travel to school literature review

Increasing children’s active travel is likely to result in net gains in the overall levels of physical activity, and in the proportion of children achieving the recommended levels of phy

Active travel to school: literature review

Dr Jan Garrard

July 2011

Contents

Executive summary _ 5

Introduction _ 5 Physical activity, active transport and children’s health 5 Health risks associated with active transport to school _ 6 Active travel to and from school in Australia and the ACT _ 7 Effectiveness of interventions aimed at increasing children’s rates of active travel to school 8 Future directions/innovations for promoting active travel for children in Australia and the ACT 8 Conclusions 9

Active travel to school: literature review _ 11

1 Introduction _ 11

2 Physical activity, active transport and children’s health 13

2.1 Health benefits of physical activity and active transport 15

2.1.1 Physical health 15 2.1.2 Mental health 18 2.1.3 Intelligence quotient and educational attainment _ 18 2.1.4 Demographic distribution of active transport _ 19

2.2 Health benefits of reduced car use _ 20

2.2.1 Air quality _ 20 2.2.2 Noise pollution _ 20 2.2.3 Climate change _ 21 2.2.4 Community liveability 21 2.2.5 Children’s independent mobility _ 22 2.2.6 Traffic congestion _ 23

3 Health risks associated with active transport to school 25

3.1 Traffic injuries 25 3.2 Exposure to air pollutants 26

4 Rates of active travel to school in Australia and the ACT _ 27

4.1 Active travel to school in Australia and internationally _ 27 4.2 Active travel to school in the ACT 28

4.2.1 Children’s overall physical activity levels _ 28 4.2.2 Children’s participation in active transport _ 29

5 Potential for mode shift to active travel to school: the role of trip distance 29

6 Effectiveness of interventions aimed at increasing children’s rates of active travel to school _ 32

6.1 Evidence reviews _ 32 6.2 Recent evaluations of active school travel interventions 33

6.2.1 Australia _ 33 6.2.2 International AST programs _ 36

6.3 Summary of the impacts of active transport initiatives in schools 36 6.4 Aggregate level change 37

7 Understanding the influences on active travel to school _ 38

7.1 Social-ecological model of active school travel 38 7.2 Perceived benefits/barriers model of active school travel _ 40

8 Future directions/innovations for promoting active travel for children in Australia and the ACT 42

9 Conclusions _ 45 References _ 46

List of acronyms and abbreviations

LTPA Leisure-time physical activity

MVPA Moderate to vigorous physical activity

The current focus on ‘active living’ has led to a growing recognition of the potential for incidental forms of physical activity Active transport provides an activity that is continuous, expends sufficient energy, can be performed by most children, does not appear to displace other forms of physical activity and is not principally performed by children who are already active Increasing children’s active travel is likely to result in net gains in the overall levels of physical activity, and in the proportion of children achieving the recommended levels of physical activity

A number of high-income countries and cities have successfully reversed the trend of

steadily increasing car travel by children and young people, while a range of Australian government policies and programs at federal, state, territory and local levels to increase active travel for children and adults have been developed and implemented Evaluation of these initiatives in Australia and overseas indicates variable effectiveness, and highlights the learning curve required to achieve the high levels of active travel among children in several European and Asian countries and cities To assist the evaluation process, this report

provides an evidence-based summary of:

 The relationships between physical activity, active transport and children’s health

 Rates of active travel to and from school in Australia and the ACT

 The effectiveness of interventions aimed at increasing children’s rates of active travel to school

 Future directions for promoting active travel for children in Australia and the ACT

Physical activity, active transport and children’s health

The child health benefits of moderate-to-vigorous physical activity (MVPA), including active transport, encompass physical, mental and social health in the form of:

 Healthy child development (bone, muscle, joint health): Moderate to vigorous

weight-bearing physical activity during childhood is essential for optimal skeletal, joint and muscle growth While no studies were found that focused specifically on active transport, walking is a weight-bearing form of physical activity with cycling less so (depending on cycling style and the terrain covered)

 Aerobic fitness: Cycling and walking to school improves cardiovascular fitness among young people, particularly girls

 Healthy weight: Indirect evidence points to a relationship between active transport and overweight/obese children, but the available evidence is not definitive

Evidence indicates that the contribution of active transport to maintaining healthy weight depends on walking or cycling trip distances

 Mental health: There is evidence of an inverse association between physical activity and some measures of child mental health, but there appear to be no studies of active transport and mental health

 Intelligence quotient and educational attainment: There is consistent evidence of a significant positive relationship between physical activity and cognitive function, and more recently between aerobic power, intelligence quotient (IQ) and educational attainment Studies were not specifically of active transport

The co-benefits of active transport not associated with leisure-time physical activity (LTPA) include:

 More equitable distribution of physical activity across some key population

demographic segments Adolescents, particularly females, are more likely to meet physical activity guidelines if they travel actively to school

 A range of physical, psychological and social health benefits associated with reduced motor vehicle use (due to replacing car trips with active trips) These include reduced air and noise pollution, and reduced traffic injuries

 Improvements in community liveability, traffic congestion, environmental

sustainability, climate-change abatement and reduced dependency on

non-renewable energy sources that impact on all community members, including

children

Health risks associated with active transport to school

The health risks associated with active transport are (i) the risk of traffic injury, (ii) exposure

to air pollutants and (iii) risk of injury (in common with other forms of physical activity such

as sport and play) Pedestrian and cyclist injuries are often compared with risk of injury as a car passenger as they are alternative forms of transport

Absolute levels of risk of child pedestrian and cyclist fatalities in Australia are low,1 although child pedestrians and cyclists have a greater risk of injury than car passengers per unit of exposure (ie distance or time travelled) Child pedestrian and cyclist fatality rates (per km travelled) in OECD countries with high rates of walking and cycling are about one-quarter of the rates in countries with low rates of these activities (such as Australia) This data

indicates the considerable potential to improve child pedestrian and cyclist safety in

Australia

1 Child pedestrian fatalities 0.86 per 100,000 child population; and child cyclist fatalities 0.39 per 100,000 child population.

Modelling studies show that if a substantial share of trips by motorised transport is

transferred to walking or cycling, the total number of road traffic crashes (including vehicle and single-vehicle car crashes, as well as pedestrian-car and cyclist-car crashes) is reduced More commonly, rates of pedestrian, cyclist and overall road traffic injuries are observed to decline as active travel mode share increases

multi-While risk-benefit analyses demonstrate the health benefits of cycling for adults outweigh the risks, no comparable studies for children or for walking were found

Active travel to and from school in Australia and the ACT

In contrast to several European and Asian countries, children’s rates of active travel to school and other destinations in Australia and the ACT are low and declining In the ACT in

1970, more students travelled to school or university by bicycle (13.1%) or walking (46.8%) than by car (12.1%)2 (Australian Bureau of Statistics 1975) By 1997, only 29.7% of students walked (22.2%) or cycled (7.5%) to full-time education (Brown and Nairn 1997) The decline over time, and current rates of active travel to school, are similar to those in Victoria (27%

of students aged 5-12 years), although higher than in the Greater Sydney Metropolitan Area (22% of primary school students) (Garrard 2010)

In 2006, 30.5% of Year 6 students in the ACT3 walked or cycled to school4 (Population Health Research Centre ACT Health 2007) Care needs to taken in comparing this rate of active travel to school with the 1997 figure (29.7%) due to differences in the study population and the measure of active transport Preliminary analysis of 2009 data indicates a statistically significant decline between 2006 and 2009 (30.5% and 24.3% respectively) in the proportion

of Year 6 students walking or cycling to school every day (ACT Health, preliminary analysis of

2009 ACTPANS data)

Cross-country comparative data show large differences in active travel to school 5 which are not accounted for by greater trip distances to school in countries with low rates of active travel In many high active travel countries, children walk and cycle to school for trip

distances that are predominantly made by car in countries such as Australia

There is also greater international variation in cycling rates than in walking rates which may account for a large part of the international variations in overall rates of active transport In countries such as Australia, car trips largely replace walking trips for distances greater than 1

km, while bicycle trips are more common than car trips for distances up to about 4 km in high active transport countries

2

Full-time students aged 5 years and over

3 These data are for grade 6 students only, but levels of active travel among young people in Australia show little variation between grades 4 and 8 (ref)

4 Five times in a typical week.

5 For example, 86% in the Netherlands, 71% in Denmark, 71% in Germany compared with 13% in the USA, 15%

in Canada and 48% in the UK

Active school travel programs in Australia have also been more successful in increasing walking rather than cycling to school This trend indicates that cycling to school will require additional attention if Australia is to move towards the high rates of active travel to school for short to medium distance trips that occur in several affluent European and Asian

countries

Effectiveness of interventions aimed at increasing children’s rates of active travel to

school

Active school travel programs typically include some combination of:

 Special walking or cycling promotion days

 A program of pedestrian and cycle training for children

 Secure bicycle parking

 Activities as part of the curriculum to promote the benefits of sustainable transport

 Physical changes to the streets around the school, such as 40 km/h limits, traffic calming, pedestrian crossings and bicycle lanes

 Developing a school travel policy and/or home-school agreement

Recent evidence reviews indicate that not all programs achieve small-to-moderate increases

in rates of active travel to school There has been little systematic assessment of the reasons for variable program impacts although, based on limited process evaluation data to date, the determinants of success are likely to include factors associated with schools and their social, cultural and built environments, program type and quality of implementation

Active travel programs are often successful in participating schools, although there is little evidence of an overall mode shift to active travel to school in countries with low rates of active travel

Future directions/innovations for promoting active travel for children in Australia and the ACT

The evidence reviewed in this report indicates that in several countries and regions

(England, Scotland, Victoria, NSW and the ACT), population levels of active travel to school have not changed despite programs with impressive impacts in some participating schools and for special events (eg walk/ride to school days and the Brisbane City Council Active School Travel program) It is therefore evident that carefully planned and well-implemented behaviour change programs are a necessary but not sufficient condition for population-level change in school travel modes

Strategic planning and a systems approach are required to move towards the levels of active travel to school enjoyed by a number of other high-income countries Denmark, Germany, the Netherlands and Japan provide models of implementing broad-based policy packages that make active travel to school a convenient, safe travel mode Effective active transport policy models are not restricted to the high active travel countries in Europe and Asia

Relatively high rates of active travel to school have been achieved in a small number of towns and cities in the USA

The greatest potential for increasing rates of active travel to school lies in encouraging more young people to walk up to about 1 km and to cycle up to about 5 km With the right

conditions, policies, education and encouragement, more children would walk or cycle to school and to other neighbourhood destinations Strategies to increase active travel to school, which incorporate school-based programs with area-wide and population-wide strategies for increasing active travel in the wider community, could include the following elements:

 Setting goals and targets (eg an increase of 5 percentage points in the walking and cycling mode share of travel to education in a 5-year period6,7)

 Specifying components of the strategy (eg incorporating the 4Es of Education,

Encouragement, Engineering, and Enforcement)

 Well-defined ‘program logic’ (ie Are we doing the right things? Is the intervention

‘dose’ appropriate? Is the program reach adequate?)

 Identify partners, responsibilities and resources (eg who is responsible for each component?)

 Evaluation/monitoring (eg including measures of travel to school in school data collection systems)

The key health promotion strategies of community participation, advocacy and

inter-sectoral partnerships will also be important in achieving these goals Many government sectors and levels have a role in increasing children’s use of healthy and sustainable

transport modes for the many short-to-medium trips that typify children’s travel in urban areas

Conclusions

This report demonstrates that increasing levels of car use are the predictable outcome of transportation policies that promote car use and constrain walking and cycling, and not the inevitable by-product of low-density suburban living in affluent countries Changes can be achieved through programs such as Safe Routes to School, Walking School Bus, School Travel Planning and Walk/Ride to School events These initiatives need to be complemented

by area-wide improvements that create supportive environments for active travel The experiences of overseas countries, cities and municipalities provide a model for sustainable transport planning aimed at increasing active travel to school in the ACT

6 This is approximately the rate at which walking and cycling to education have declined in the last 40 years in Victoria

7 The recent White House Task Force on Childhood Obesity Report to the President (Solving the problem of

childhood obesity) set a target of an increase in bike/walk trips to school in the USA of 6.5 percentage points by

2015

While implementing and assessing active travel initiatives in participating schools is

important, key questions to consider include (i) the program and contextual factors that shape the effectiveness of interventions; (ii) the sustainability of change; (iii) the reach of active travel initiatives; and (iv) the role of supportive community-wide measures Public health strategies in areas such as tobacco control, road safety and child immunisation are successful because they achieved measurable improvements at the population level and not just in selected schools or communities Consequently, the well-documented benefits of active travel will be realised when measurable change occurs at the population level

Active travel to school: literature review

1 Introduction

Physically active children are healthier, happier and more socially connected than children who have more sedentary lifestyles (US Department of Health and Human Services 2008; WHO 2008), yet data from the 2007 Australian Children’s Nutrition and Physical Activity Survey shows only 32% of Australian children aged 9-16 years meet the recommended levels8 of moderate to vigorous physical activity (MVPA) (Department of Health and Ageing 2008) Additional pedometer data showed the majority of Australian children aged 9-16 did not meet the recommended number of steps per day (15,000 for boys and 12,000 for girls), and this number declined rapidly with age (only 13% of boys aged 14-16 years and 16%9 of girls aged 14-16 met the recommended number of steps) (Department of Health and Ageing 2008)

Substantial changes in Australian lifestyles, urban environments and transport systems have led to changed physical activity patterns among children in recent decades (Olds et al 2007) Active transport10 has particularly declined dramatically in countries such as the US, UK and Australia where car travel has become the predominant form of personal mobility (Salmon

et al 2005; van der Ploeg et al 2008) These changes are not primarily due to increased travel distances to school as they have occurred for all trip distances, including those considered feasible for walking (up to 1 km) and cycling (up to 5 km) (see Section 5)

In 1970, more students in the ACT travelled to school or university by bicycle (13.1%) or walking (46.8%) than by car (12.1%)11 (Australian Bureau of Statistics 1975), but by 2009, preliminary data analysis indicated only 24.3% of Year 6 students12 walked or cycled to school13 (preliminary analysis of 2009 ACTPANS data, ACT Health)

Active travel to school is also associated with active travel to other destinations (Dollman and Lewis 2007), making walking or cycling to school indicative of wider use of active travel modes Increasing numbers of Australian children are therefore missing out on incidental forms of physical activity such as active travel to school and other neighbourhood

destinations that were once an integral part of daily life The decline in active transport has not been accompanied by increased participation in sport and active recreation which has remained relatively steady between 2000 and 2009 (Australian Bureau of Statistics 2009))

Full-time students aged 5 years and over, usual method of travel to education

12 These data are for Year 6 students only, but levels of active travel among young people in Australia show little variation between Years 4 and 8

13

Five times in a typical week.

While it is difficult to accurately measure all forms of children’s physical activity, and

comprehensive data from longitudinal surveys are not available, it is likely that substantial reductions in incidental forms of physical activity are contributing to a decline in children’s aerobic fitness (Olds et al 2007)

Until recently, promoting physical activity for children has focused on increasing children’s participation in sport and exercise programs (Dobbins et al 2009) However, very few

countries have succeeded in increasing physical activity levels in the overall child population through policies, programs and campaigns aimed at encouraging more children to

participate in leisure-time physical activities such as sport and exercise Lack of level impact for these strategies has led to a shift in focus for physical activity promotion from ‘deliberative’ leisure-time sport and exercise programs to ‘incidental’ activity through active living (Sallis et al 2006)

population-Active transport is a key component of active living, and the evidence base for the ‘health through physical activity’ benefits of active transport is growing Modelling of physical activity patterns in Australian adults demonstrates the potential for relatively small (and potentially achievable) increases in active travel to impact on the proportion of Australians who are adequately active If people who are currently classified as inactive walked or cycled for an additional 20 minutes three times per week, the proportion of adequately active Australian adults would increase from 57% to 72% (Garrard et al 2011) Consequently, the public health potential for active transport is large, even at modest amounts and

frequency of activity, and especially if currently inactive people adopt some degree of walking or cycling

Equivalent modelling has not been conducted for children in Australia, but the results are likely to be similar to those for adults For example, studies in the UK report that adolescent girls (a population segment that has low levels of leisure time physical activity) are six to eight times more likely to meet recommended levels of physical activity if they travel

actively to school (Smith et al 2008; Voss and Sandercock 2010) These, and other findings, indicate that active transport does not ‘displace’ other forms of physical activity and is not undertaken principally by children who are already active (Davison et al 2008) Rather, increases in children’s active travel are likely to result in net gains in children’s levels of physical activity and in the proportion of children achieving recommended levels of physical activity (Davison et al 2008; Voss and Sandercock 2010)

A number of industrialised countries and cities have successfully reversed the trend of steadily increasing car travel by young people The proportion of the total distance travelled

by 10-14 year-olds using active modes is 33.5% in the Netherlands, 14.4% in Switzerland and 13.8% in Germany In contrast, only 4.6% of the total distance travelled by young people in

Melbourne14 is undertaken using active modes (Christie et al 2004; Ironmonger and Norman 2007) As discussed in Section 5, these differences are not primarily due to longer trip

distances (including to school) in Australia, as many of the active trips made by children in high active travel countries are for trip distances that are predominantly made by car in Australia and the USA

Children in countries that have successfully reversed unsustainable and unhealthy increases

in rates of driving children to school and other destinations achieve high levels of physical activity ‘incidentally’, at low cost, without children and/or their parents having to find the time, motivation and resources to participate in organised sports, exercise or fitness

programs Active transport as a form of incidental activity has a number of co-benefits not associated with the more ‘deliberative’ forms of leisure-time physical activity as illustrated

in Figure 1 and Table 2

A number of Australian government policies and programs at federal, state, territory and local levels have been developed and implemented with the aim of increasing active travel for children and adults Evaluation of these initiatives in Australia and overseas indicates wide variations in effectiveness and highlights the learning curve required to achieve the high levels of active travel among children that occurs in several other high-income

countries and cities

This report therefore provides an evidence-based summary of:

 The relationships between physical activity, active transport and children’s health

 Rates of active travel to and from school in Australia and the ACT

 The effectiveness of interventions aimed at increasing children’s rates of active travel (principally to school, which has been the focus of nearly all active travel interventions for children)

 Future directions/innovations for promoting active travel for children in Australia and the ACT

This report draws on Australian and international research, evaluation and current practice, with ACT data included when available The focus is on primary school aged children (5-12 years), with older ages included when the data covers a wider age range (eg 10-14 years) The generic term ‘travel to school’ refers to travel to and from school ‘Active travel’ and

‘active transport’ refer principally to walking and cycling, as this is the focus of most

research into children’s use of active transport

2 Physical activity, active transport and children’s health

The child health benefits of moderate to vigorous physical activity (MVPA) encompass physical, mental and social health in the form of:

14 Melbourne data has been used in the absence of Australian national data The Melbourne data is for 0-14 year-olds in the Melbourne Statistical Division, 1994-1999

 Healthy child development (bone, muscle, joint health)

 Improvements in community liveability, environmental sustainability,

climate-change abatement and reduced dependency on non-renewable energy sources that impact on all community members (including children)

The multiple health and social benefits of active transport are summarised in Figure 1, and evidence in each of these areas is briefly reviewed

Figure 1: Health and health-related benefits of active transport for children

The Australian Department of Health and Ageing (2004) recommends that children should accumulate at least 60 minutes (and up to several hours) of MVPA each day Moderate-intensity physical activity is defined as between 3-6 METs,15 or 3-6 times the energy

expenditure at rest (Ainsworth et al 2000), with walking at the lower end of the range and cycling, which is about twice the intensity of walking, at the top end of the range

Walking and cycling provide physical activity which can be performed by most adults and children that is continuous and of sufficient intensity (Garrard et al 2011) Research into

15 The Metabolic Equivalent of Task (MET) expresses the energy expenditure of physical activities as multiples

of the resting metabolic rate; with 1 MET defined as the metabolic rate at rest

Benefits of active transport

Increased physical activity

Demographic distribution of PA

Rduced car use

Air quality

Noise pollution

Climate change

Community liveability congestionTraffic

active transport as a form of MVPA is relatively recent, and while much of the evidence reviewed below is for MVPA in general, many of the findings may also apply to active

transport.Direct evidence of the health benefits of active transport as a form of MVPA is also used whenever possible

2.1 Health benefits of physical activity and active transport

2.1.1 Physical health

Healthy child development (bone, muscle, joint health)

Moderate to vigorous weight-bearing physical activity during childhood is essential for optimal skeletal, joint and muscle growth Physical activity creates higher bone density and bone mineral content which are vital for protecting against osteoporosis in later life

(Matthews et al 2006) While the benefits of weight-bearing physical activity for children are well documented, no studies that focused specifically on active transport as a form of

weight-bearing physical activity were found However, walking is a weight-bearing form of physical activity while cycling depends on the style (eg standing up/sitting down) and terrain covered

In a large UK study, Voss and Sandercock (2010) examined the likelihood of being classified

as ‘fit’ according to travel mode (with ‘passive transport users’ as the reference group) Consistent with other studies, the greatest benefits were for cycling compared with walking, and for girls compared with boys Girls were nearly eight times more likely to be classified as

‘fit’ if they cycled to school after adjusting for covariates16 including other forms of physical activity The finding of a marked improvement in fitness for girls who walk or cycle to school reflects the rapid deline of leisure-time physical activity among adolescent girls in countries such as the UK and Australia (Department of Health and Ageing 2008)

Healthy weight

The proportion of overweight and obese children aged 5 – 17 years increased from 20.8% in

1995 to 24.9% in 2007-08 (Australian Bureau of Statistics 2009) Obesity in young people is

16 A covariate is a variable that is possibly predictive of the outcome under study A covariate may be of direct interest or it may be a confounding or interacting variable

associated with psychological problems, inappropriately fast growth and development, abnormal lipid/body fat profile, high blood pressure and abnormal glucose

tolerance/metabolism (Kelty et al 2008; The Obesity Society nd) Obesity during childhood, particularly adolescence, is related to obesity as an adult and the associated increased risks

of developing chronic diseases as an adult (The Obesity Society, nd)

Indirect evidence points to a relationship between active transport and overweight/obese children, but the available evidence is not definitive Cross-country comparative data shows

an inverse relationship between distance walked and cycled per child (10-14 years) per year and being overweight/obese (see Table 1 and Figure 2), while studies within countries such

as Australia with low rates of active travel show no consistent relationship (Booth et al 2006; Davison et al 2008; Lee et al 2008; Voss and Sandercock 2010) This may be due to the limited range of energy expenditure on active travel in Australia (ie children in the highest active travel categories in Australia have low levels of active travel compared with children

in several European and Asian countries)

Children in European and Asian countries with high active travel rates frequently cover relatively large distances by foot or bicycle (see Tables 1 and 3) which contributes to energy expenditure and maintenance of a healthy weight Australia’s low cycling rates potentially lead to lower energy expenditure than countries where children have relatively high rates of cycling to school Consistent with this explanation, the Kiel Obesity Prevention Study in Germany found that active commuting to school did not affect Body Mass Index (BMI) or fat mass, but there was a decrease in fat mass for longer walking or cycling trip distances

(Landsberg et al 2008) Active commuting comprised 28.4% of overall physical activity

In population terms, active transport cannot prevent all young people from becoming

overweight, or provide a stand-alone intervention for weight loss However, it will probably contribute to reducing the prevalence of overweight and obese young people

Table 1: Distance walked and cycled per child (10-14 years) per year (kilometres)

(Source: Christie et al, 2004)

child per year (kilometres)

Distance cycled per child per year (kilometres)

Proportion of total distance travelled using active modes (%)

Figure 2: Children’s active travel distance and overweight/obesity

(Melbourne Statistical Division travel data included in absence of Australian national data

for children’s active travel distance) (Sources: Christie 2004; International Obesity TaskForce 2009)

17 Walking only - cycling rates are not included in US data because they are very low

18 Melbourne Statistical Division (Greater Melbourne Metropolitan Area), children aged 0-14 years, VATS

1994-99 average (Ironmonger and Norman 2007)

2.1.2 Mental health

Rates of mental health problems in Australian children and adolescents are increasing (Australian Bureau of Statistics 2007) Several cross-sectional studies have demonstrated inverse associations between physical activity and psychological distress in adolescents (Hamer et al 2009), although there is limited research on physical activity and psychological factors in younger children (≤ 12 years of age), or from longitudinal studies or intervention studies

A recent study involving younger children found television and screen entertainment (TVSE) time and physical activity were independently associated with children’s Strengths and Difficulties Questionnaire (SDQ) total difficulties score after adjustment for age, gender, index of deprivation, single-parent status, chronic medical conditions and various dietary indicators The SDQ incorporates subscales of hyperactivity, emotional symptoms, conduct problems and peer problems (Hamer et al 2009) A numbers of authors note the cross-sectional nature of most studies in this area cannot rule out the possibility of bias from unmeasured variables

2.1.3 Intelligence quotient and educational attainment

A number of studies have reported that higher aerobic power among young people is

associated with increased IQ, improved cognitive functioning and higher educational

attainment (Sibley and Etnier 2003; Åberg et al 2009)

A recent landmark study involving all Swedish men born between 1950 and 1976 who were enlisted for military service at age 18 (N = 1,221,727) found that cardiovascular fitness, measured by ergometer cycling, was positively associated with intelligence (Wechsler Adult Intelligence Scale), school achievement and subsequent socioeconomic status after

adjusting for relevant confounders (Åberg et al, 2009) An earlier meta-analysis of the

relationship between physical activity and cognitive functioning in children found a

significant positive relationship between physical activity and cognitive function (Sibley and Etnier 2003)

Consistent with these findings, a review of “Physical Education, Physical Activity and

Academic Performance” conducted by the US Active Living Centre19 concluded that:

 Studies consistently show that more time in physical education and other based physical activity does not adversely affect academic performance

school- In some cases, more time in physical education leads to improved grades and

standardised test scores

 Physically active and fit children tend to have better academic achievement

 Evidence links higher levels of physical fitness with better school attendance and fewer disciplinary problems

19

http://www.activelivingresearch.org/files/Active_Ed_Summer2009.pdf

 There are several possible mechanisms by which physical education and regular physical activity could improve academic achievement, including enhanced

concentration skills and classroom behaviour

While there is no direct evidence that active travel to school improves cognitive functioning

or educational attainment, the link between active travel and aerobic fitness described in Section 2.1.1 suggests that active travel as a form of MVPA might contribute to these

cognitive and educational benefits

2.1.4 Demographic distribution of active transport

There are indications, both in Australia and internationally, that active transport is a more socially inclusive form of MVPA than leisure-time physical activity due to more evenly

spread participation across demographic segments of the population This is particularly the case for age and gender of Australian children Data from the Australian Children’s Nutrition and Physical Activity Survey indicate that active travel does not decline with age and has similar participation rates for girls and boys at most age levels as opposed to sport and play (Figure 3) These age- and gender-specific physical activity patterns are consistent with the findings described in Section 2.1.1 which show that girls (and adolescent girls in particular) are several times more likely to meet physical activity guidelines if they travel actively to school (Smith et al 2008; Voss and Sandercock 2010)

The more socially inclusive, population-wide participation in physical activity associated with active travel in high active travel countries might also help to explain the inverse

relationship between active travel and obesity (see Figure 2)

Figure 3: Age and gender-related patterns in MVPA and some of its components [free play, sport

and active transport (AT)]

(Source: Department of Health and Ageing 2008)

Another key area of distinction between leisure-time physical activity and active transport is the range of co-benefits associated with reduced motor vehicle use when active transport trips replace car trips

2.2 Health benefits of reduced car use

pollution costing between $0.4 billion and $1.2 billion Air pollution caused by motor

vehicles also accounted for between 900 and 2000 premature deaths with an estimated cost

of between $1.1 billion and $2.6 billion (Bureau of Transport and Regional Economics 2005) These premature deaths, labelled ‘the silent road toll’, are comparable to the number of people killed in road crashes (1368 in Australia in 2010)

Motor vehicle related air pollution also affects children, with deficits in lung function growth showing a linear relationship with air pollution (Gauderman et al 2004) A study of proximity

to engine exhaust emissions in Great Britain, and the link with children dying from

cancer/leukemia, found maximum effects at short (0.1–0.5 km) effective ranges, tapering to neutral after 3 km Over 24% of child cancers are attributable to these exposures with roads exerting the major effect (Knox 2006)

The Australian Institute of Health and Welfare (2010) developed a method for estimating the contribution of air pollution to asthma hospitalisations The study, which used the adjusted results of Melbourne in 2006 as a case study, found:

 Approximately 3% of all asthma hospitalisations in Melbourne in 2006 were related

to exposure to nitrogen dioxide (60% due to motor vehicle emissions)

 Approximately 4% of asthma hospitalisations of 0–14 year olds were related to particulates in the air (30% due to motor vehicle emissions)

2.2.2 Noise pollution

Environmental noise impacts on people’s lives through annoyance, sleep disturbance,

reduced work or school performance, stress and anxiety, reduced enjoyment of home life and other physical health effects Exposure to noise leads to cognitive impairment in

children and affects their ability to study and learn (World Health Organization: Regional Office for Europe 2011)

Surveys and noise measurements conducted by the Victorian Environmental Protection Authority (EPA) in late 2006 at 50 sites across the inner, middle and outer suburbs of

Melbourne found that transport is the main (and loudest) source of noise pollution Seventy

percent of people hear traffic noise in their homes and over one million Victorians are annoyed by it (Environmental Protection Authority 2007)

Traffic noise was also identified as a key community concern for Australians with

‘dangerous/noisy driving’ the most frequently reported perceived neighbourhood problem with crime or nuisance These concerns were ahead of vandalism/graffiti, housebreakings, drunkenness, louts/gangs, car theft and illegal drugs (Australian Bureau of Statistics 2010)

2.2.3 Climate change

Transport is a significant and growing source of the greenhouse gas emissions that

contribute to climate change It accounts for 14.6% of total Australian emissions, having risen by 29% between 1990 and 2008 (Department of Climate Change and Energy Efficiency 2010).The transport sector contributes a significantly greater proportion to total emissions

in the ACT than at the national level, and accounted for 23% of total ACT greenhouse gas emissions in 2008 (Department of the Environment, Climate Change, Energy and Water, 2010)

The environmental consequences of climate change, which include sea-level rise, degraded air quality and extreme weather events (resulting in droughts, floods, heat waves, more intense hurricanes and storms) affect human health both directly and indirectly The health effects of climate change (USA Interagency Working Group on Climate Change and Health

2009 nd) include:

 Heat-related mortality and morbidity

 Injuries

 Drowning

 Vector, food and water-borne diseases

 Food and water shortages and malnutrition

 International conflict

 Cardiovascular disease, stroke and cancer

 Exacerbation of respiratory diseases such as asthma

 Respiratory allergies and airway diseases

 Mental health and stress-related disorders

2.2.4 Community liveability

Children are particularly vulnerable to the impacts of high levels of car use in urban areas

The provision of road space to enable high volume, high speed car travel comes at a cost to other road users and local residents in terms of community disruption, noise pollution, social isolation, urban sprawl and restrictions on children’s independent mobility,

opportunities for outdoor play and social interactions (Dora and Phillips 2000; Social

Exclusion Unit 2003; Ewing et al 2006; Carver et al 2008; Carver et al 2008a; Litman 2009) Appleyard’s original research, which found heavy traffic is associated with reduced street-based activities and social interactions between neighbours (Appleyard and Lintell 1980), has now been replicated in other settings (Bosselmann and MacDonald 1999; Hart 2008) In terms of social interactions among children, ’socialising with friends‘ was one of the three most frequently cited reasons for liking walking to school based on a survey of primary school students conducted as part of the evaluation of the Victorian Ride2School program (Garrard et al 2009)

There is consistent evidence that parents restrict their children’s walking and cycling to school because of injury concerns in countries like Australia (Garrard et al 2009; McDonald

et al 2010) These risk perceptions can contribute to what Horton (2007) refers to as the

’fear of cycling‘ Jacobsen et al (2009) also describe how motor vehicle domination of

transport infrastructure creates fear of walking and cycling, leading to declining levels of active transport, and setting in train a vicious cycle of continuing retreat of cyclists and pedestrians from public spaces increasingly dominated by cars

In contrast, the injury risks posed by increasing numbers of motor vehicles in urban areas in the Netherlands during the 20th century led to a comprehensive package of measures to curb motor vehicle use in urban areas and improve pedestrian and cyclist safety These included extensive, high-quality cycling infrastructure‘ and establishment of the legal

responsibility of car drivers to avoid collisions with cyclists and pedestrians The Dutch approach is: “cyclists are not dangerous; car drivers are: so car drivers should take the responsibility for avoiding collisions with cyclists” (Ministry of Transport Public Works and Water Management 2009) These measures have contributed to a cycling (and walking) environment that is both safe and pleasant, and where parents can confidently allow their children to walk and cycle independently

There is also evidence that the more compact, permeable urban designs that support cycling and walking lead to crime reduction through increased street activity and ’natural

surveillance‘ (Cozens et al 2005) In a detailed study in the UK, Hillier and Sahbaz (2006) concluded that reduced risk of crime arises from “the ordinary co-presence of people that everyday movement and activity brings.” This improves personal security for all community members

2.2.5 Children’s independent mobility

An under-recognised consequence of excessive car use in urban areas is parental

curtailment of children’s independent mobility which is the freedom to move about

unaccompanied within their neighbourhood or community (Zubrick et al 2010) A number of studies have documented substantial declines in children’s independent mobility over time

in countries such as the UK and Australia In 1971, nearly three-quarters of 7-11 year-old

children in England were allowed to cross roads alone By 1990 the proportion had fallen to about a half (Hillman 1993)

The reduction in independent mobility was even greater for cycling on the roads Between

1971 and 1990, child bicycle ownership increased from two-thirds to nine in ten, but the proportion of children who said they were allowed to use them on the roads declined from two-thirds to a quarter (Hillman 1993) Children’s independent mobility in England has decreased further in recent times In 2002, 78% of 7 to 10 year olds were accompanied by their parents to school, increasing to 85% in 2006 (Department for Transport 2008)

Children’s outdoor autonomy also varies across countries In the early 1990s, German

children had much more travel freedom than their English or Australasian counterparts For example, 90% of German 9 year olds were allowed to cross roads alone compared with 50%

of English or Australasian children (Hillman et al 1990; Tranter 1996)

Independent mobility plays an important role in the development of children’s spatial, motor and analytic skills, environmental competence, social and emotional development and resilience (Prezza et al 2005; Malone 2007; Zubrick et al 2010; Badland et al 2011) It has also been argued that children have a right to move about safely in the outdoor

environment This right has been increasingly eroded by systematically prioritising the needs

of motorists over the needs of children to move around their neighbourhoods without having to ask an adult to escort them (Rosenbaum 1993)

2.2.6 Traffic congestion

Traffic congestion in Australia has both health and economic costs The current economic costs of congestion in Australian capital cities are estimated to be $9.4 billion per year, including $110 million in Canberra (Bureau of Transport and Regional Economics 2007) Traffic congestion, car space requirements and costs are a major concern for a number of school communities Data for the ACT are not available, but in 1999, children being driven to school accounted for about 17% of all trips by all people in the Melbourne Statistical

Division during the morning peak period between 8.30 and 9 am Additionally, 39% of car trips to school were home-school-home trips (ie not part of linked trips from home to school

to other destinations) (Morris et al nd)

Preventing traffic congestion and avoiding the necessity to provide extensive car-parking facilities at schools have been major factors in the promotion of cycling to school in the Netherlands (Ministry of Transport Public Works and Water Management 2009) Rose (1999) noted in an evaluation of the Safe Routes to School program that concerns about traffic congestion and car-parking at schools in Australia can be a major motivation for implementing active school travel programs

In summary, this section briefly reviewed the multiple health and social benefits of active transport and reduced car use Active transport constitutes an appropriate form of MVPA, in

many respects similar to the more traditional and widely recognized LTPA Active transport also has a number of co-benefits not generally associated with LTPA These have been described briefly above, and are summarised in Table 2

Table 2: Comparison of benefits of active transport and leisure-time physical activity

Characteristics and benefits

of active travel (AT)

Characteristics and benefits

of leisure-time physical activity (LTPA)

Sufficient to achieve a health

groups for physical activity

Addresses key barriers to

physical activity:

 Lack of time

 People believe they

are ‘not sporty’

3 Health risks associated with active transport to school

3.1 Traffic injuries

Active transport also carries a risk of injury in common with other forms of physical activity such as sport and play Pedestrian and cyclist injuries are often compared with risk of injury

as a car passenger since walking and cycling are alternative forms of transport A

comparative analysis of 30 OECD countries found highly variable traffic crash fatality rates for young people aged 0-16 years Fatality rates varied by country, travel mode (walking, cycling, car passenger), measures of traffic exposure (fatalities per population, number of trips, or distance travelled), road safety policies and a range of socio-demographic factors (Christie et al 2004; Christie et al 2007)

Absolute risk of fatality is low for all modes of travel in most OECD countries For example, Australia has:

 1.69 child car passenger fatalities per 100,000 child population (ranked 21st20 out of

26 OECD countries)

 0.86 child pedestrian fatalities per 100,000 child population (ranked 13th)

 0.39 child cyclists fatalities per 100,000 child population (ranked 13th)

An Australian child is therefore almost twice as likely to be killed as a car passenger than as

a pedestrian, and more than four times as likely to be killed as a car passenger than as a cyclist (Christie et al, 2004)

While these absolute levels of risk are comparatively low, relative risks based on traffic exposure (ie relative fatality rates per trip or per kilometre travelled) result in a different pattern of risks by travel mode Exposure-based relative risks are generally higher for

pedestrians and cyclists than for car passengers (about 4-10 times), but with large variations between countries Even in the current traffic environments in US and NZ21, one fatality occurs for about 10 million km walked or cycled, decreasing to one for about 100 million in the high active travel countries (Christie et al, 2004)

There is little evidence of a steady gradation in pedestrian and cyclist fatality rates across countries (Christie et al 2004) Rather, there is a clustering effect with Sweden, the

Netherlands, Finland, Germany and Denmark classified as the ‘top performers’ for

pedestrian safety These countries have a strong commitment to fostering high levels of safe walking and cycling, and most have implemented a comprehensive package of integrated traffic safety measures including:

 A strong approach to infrastructure measures for pedestrian safety

20

Japan is ranked first (i.e safest), with a fatality rate of 0.37 per 100,000 child population; with Turkey ranked

26th (4.03 per 100,000) Australia, the US and NZ have among the highest fatality rates for child car passengers (21st, 23rd and 24th respectively) due in part to the distance travelled as a car passenger (Christie et al, 2004)

21

Australian data are not available