Introduction
The importance of regular physical activity for promoting both physical and mental well-being among children and adolescents is widely recognized (1, 2). Active school transport can provide a significant source of physical activity, and can enable children to meet the WHO guidelines of 60 min of physical activity per day (3, 4). Modes of active transport between home and school – walking and cycling – have been associated with health benefits and give a sense of increased independence to young people (5). Thus, it has been argued that they should be prioritized over transport by motor vehicle. Active transport is one of the priority areas within the Physical Activity Strategy for the WHO European Region 2016–2025 (6). The National Physical Activity Plan for Ireland (7) recognizes the many benefits of active transport beyond immediate physical activity gains and aims to develop walking, cycling and general recreational and physical activity infrastructure. In Ireland, the Green Schools initiative encourages schools to have an active travel plan that encourages pupils to use alternatives to a car, and supports and promotes active school transport (8).
Studies on the health-related impacts of children’s active travel have primarily focused on physical well-being and health determinants. There is clear and consistent evidence that children and adolescents who engage in active school transport report improved physical health such as lower body weight, healthier body composition, and better cardiovascular outcomes, including lower blood pressure and cholesterol levels (1, 3, 9).
There is a large body of empirical evidence highlighting the benefit of physical activity to young people’s mental well-being (e.g., 10, 11). However, there is a lack of evidence measuring the impact of active travel on the mental well-being of young people (12), particularly in Ireland. A recent scoping review of children and adolescent’s active travel in Ireland identified 19 studies exploring active travel, however none of these included mental well-being outcome measures (3). A limited number of international studies have found positive associations between active school transport and measures of mental health or mental well-being. One study in China reported that children in grades 4–12 (no age range reported) who engaged in active travel were less likely to report depressive symptoms as assessed by the Children’s Depression Inventory, when compared to children who did not (1). A study examining psychological well-being among Austrian children from 3rd and 4th grade (mean age: 9.6) found that active travel modes (walking, cycling and scooter) were associated with higher psychological well-being than passive transportation (using a car as a passenger or using public transport), assessed by visual analogue scales on their mood during the first and the last school lessons (12). Children cycling to school reported the highest psychological well-being, and children in general had a very positive attitude to cycling.
Active school transport is influenced by multiple health determinants, specifically: individual (age, gender), social (family, friends) and environmental factors (infrastructure, roads) (13). Sun et al. (1) reported that children from rural areas were more likely than urban children to choose active transport to school. Children from families with low socio-economic status were most likely to report walking, while children with high socio-economic backgrounds were most likely to report passive transportation.
The National Cycle Policy Framework in Ireland (14) acknowledges the importance of these determinants. It contains many objectives which aim to improve cycling through making changes in contextual factors, such as providing and maintaining cycling-friendly roads, ensuring that cycling and public transport systems are integrated, and improving driver education and standards in a way that private vehicle drivers observe the safety needs of cyclists. A study of barriers and promoters of active travel among school-aged children in Ireland (15) found that children from urban and disadvantaged schools were more likely to have actively traveled to school. Proximity to the school was the most frequently reported determinant that influenced active travel. In countries with a low prevalence of cycling, adolescent girls are much less likely to use a bicycle than boys, thus indicating that gender may have an impact on active school transport behaviours (5).
These findings from the literature suggest that a wide range of factors influence active travel in a complex way. The association of active school transport and mental well-being may be influenced by such determinants, including family affluence or area of residence (1, 16, 17).
This study examines the modes of transport to or from school and their associations with various dimensions of mental well-being of school-aged children in Ireland. While we were unable to find sufficient previous research to set specific hypotheses, we anticipated that commuting to and from school by cycling and walking would be associated with better mental well-being outcomes and that these associations would be influenced by sociodemographic factors such as gender, age, family affluence and area of residence.
Discussion
Our results indicate that, in general, children who used cycling to commute to and from school report more positively on mental well-being indicators than those who use public transport on their way to and from school. Their scores, however, were not always statistically different from those using a private vehicle. Those who reported using a private vehicle or walking, usually scored in between the other two groups. When controlling for sociodemographic variables, the effect of mode of transport was either significant but marginal (for well-being, mental health problems and life satisfaction), or lost statistical significance (for self-esteem, body satisfaction, and health complaints). Cyclists, however, had a robust advantage compared to the other groups when they rated their health: they were significantly more likely to report excellent health, even after controlling for sociodemographic variables.
We observed a substantial imbalance across different modes of transport. Less than 4% of children reported cycling for the main part of their way to and from school, while more than 46% reported they traveled by a private vehicle. This imbalance might be attributed to transport infrastructure and its relationship with social inequalities in Ireland. The multivariate results indicate that both family affluence and area of residence (urban or rural) have some impact on the association between mode of transport and mental well-being. Children who are allowed and encouraged by their parents to use bicycles to commute to school are likely to be living relatively close to their school, and it seems reasonable to assume that the infrastructure is also deemed safe by the parents (e.g., there is a separate bike lane, or car traffic on the roads is low). Similar factors, such as social cohesion within the local community may also influence parents’ decisions on allowing their children to actively travel to and from school (13). The main factor which seems to be associated with mental well-being, was age – to such an extent that for most outcomes it obscured the effect of mode of transport. When we had conducted the analyses without controlling for age, the models controlled for other sociodemographic variables were very similar to the baseline models. Age distribution across modes of transport was imbalanced: younger children were more likely to report cycling to and from school, while children walking or using a private vehicle on the way to and from school were somewhat older; children who used public transport were the oldest. From the data we cannot infer the reason for this imbalance. A potential explanation is that in Ireland, many children attend primary schools relatively close to their homes, but post-primary schools are larger and generally further away – multiple primary schools act as ‘feeder’ schools to post-primary schools. Therefore younger children, attending primary schools, may have more opportunity to cycle to and from school, while students at post-primary schools may have to use public transport. There is evidence from international (27) as well as Irish (28) studies that mental well-being in children and adolescents decreases with age, medium and late adolescents becoming more vulnerable to low life satisfaction and depressive symptoms than early adolescents.
Children who use public transport to and from school reported poorer mental well-being outcomes than the other groups. Beside age, this may also be influenced by other family or contextual factors, such as low socio-economic status (although the models adjusted for family affluence but not for age rendered patterns similar to the baseline models). Young people who live in socio-economically disadvantaged neighbourhoods have lower rates of physical activity (16).
We found that relatively few children cycle to and from school, and only around one fifth (18.2%) of them are girls. Boys and girls were roughly equally likely to report using the other three modes of transport. We cannot infer the reasons for this gender imbalance in cycling from our data. However, a qualitative study of girls from New Zealand demonstrated that some adolescent girls report feeling self-conscious in cycle clothing, and that the perceived lack of femininity of cycling discouraged them (5). Girls may have greater concerns about dangers related to cycling and have lower self-perceived cycling ability and skills (e.g., knowledge of local cycle routes and bicycle maintenance). Girls’ parents may also be more worried and restrictive about their daughters’ cycling. Image, in relation to their maturity and femininity, desire not be seen doing physical exercise, and the gendering of cycling have been linked to girls’ decisions to not use bicycles (5).
There are other important factors that may impact the relationships between mode of transport to school and mental-wellbeing. One such factor is experiencing peer violence. Among schoolchildren participating in the 2009/2010 HBSC study in Canada, it was demonstrated that bullying victimization was significantly more frequent in children who used active transportation compared to their peers who used other ways of transportation (OR = 1.26) (29). Given the ample evidence for the association of bullying victimization and negative mental well-being outcomes in adolescence (30), we anticipate that bullying may mediate or moderate the link between modes of transportation between school and home and mental well-being in young people.
Almost half of the children in our study reported commuting via private vehicles, illustrating that Ireland has a car-centred traffic culture. Children in Ireland (31) travel between home and school at peak traffic flow periods, which also increases local traffic congestion and pollution. Children in rural areas were more likely to report using a private vehicle, which may be attributed to the fact that public transport largely serves urbanized areas, and rural public transport is scarce. Lack of accessible public transport in rural Ireland is understood as a form of social exclusion (32). For many rural children whose parents don’t have a car or cannot give them a lift, a school bus is the only option to commute between home and school (31). This may also explain our findings that public transport users reported the poorest mental well-being outcomes. Another environmental factor determining which mode of transport is used by children is the distance between home and school (29). Further investigation is needed to better understand which factors influence children’s and their parents’ preferred modes of transport in Ireland, why using public transport is associated with poorer mental well-being, and why cycling shows a gendered pattern that is unfavourable for girls.
Relative family affluence and area of residence had a relatively small but significant influence on the associations of modes of transport and mental well-being outcomes. There are other environmental and contextual factors which are documented to influence active travel to school. In a Canadian study with 397 schools (33), school-level factors (policies and infrastructural investments such as theft-proof bicycle racks) as well as attributes of the environment (rubbish in the streets, crime, and substance abuse) had an impact on children’s active travel. A large portion (42%) of schools were located on high-speed roads not suitable for active travel and 14% lacked a sidewalk leading to the school. These findings suggest that in addition to family affluence and area of residence, attributes of neighbourhoods (e.g., how safe the area or route to school is for cycling, social cohesion, norms around different modes of transport) should be considered in future investigations. Irish children themselves have recognized multiple determinants of active travel, and their complexity, and highlighted the need for a multi-sectoral approach to this issue (15).
This study is strengthened by use of a nationally representative and adequately powered sample. Moreover, internationally comparable measures of mental well-being were used. However, there are some limitations. The measures of mental well-being used in our study are general rather than specific. Other confounder variables (such as bullying victimization, family violence, family or peer support, and distance between school and home) may have an impact on the association between mental well-being and modes of transport. One may argue that we should have included those children (around 12% of the sample) who use discordant modes of transport to and from school. While excluding their responses meant a data loss, if their mental well-being had been associated with mode of transport, including children using discordant modes of transport would have confounded the results. Further studies, using structural equation modeling, are needed to situate mode of transport between school and home as a determinant of adolescent mental well-being.
Nonetheless, our results support the argument that cycling is associated with better self-perceived health, which gives further justification to policy actions to promote cycling in children, such as those reported by the Irish Green-Schools Transport initiative (8). Encouraging girls and older adolescents to use bicycles to commute between school and home is likely to have a positive indirect effect on their physical and mental well-being.
Active transport is increasingly recognized as a way to advance multiple agendas, including improving individual physical activity, traffic management, and environmental protection (9). It seems worthwhile to invest in developing cyclist-friendly infrastructures, training on roads and cycling safety for children and families. The Irish National Cycle Policy Framework (14) highlighted the need for “a mandatory national cycling proficiency program for all school children in Irish schools starting at primary level and continuing in a graduated manner through to secondary level” (p. 35). To our knowledge, this program has not been implemented since the publication of the framework, though the recent program for Government has pledged an increase of expenditure on cycling from 2 to 10% of the national transport budget. Our results indicate that such policy actions could be successful, but attention to current and potential social, environmental and infrastructural inequalities must be incorporated.