Research: Mode Share and Travel Behavior

The built environment—which includes buildings, streets, parks, and other man-made physical surroundings—affects a person’s choices regarding opportunities for physical activity and the safety of engaging in physical activity.

Overview

Mode share describes the percentage of trips made or of travelers using a given form of transportation (walking, bicycling, public transportation, or private vehicle). Mode share is influenced by the built environment—the buildings, streets, parks, and other human-made aspects of the physical surrounding (Ward et al., 2015). The built environment can affect a person’s choices regarding forms of travel, opportunities for active transportation and physical activity (; Duncan et al., 2016; Brown et al., 2013), and safety while engaging in active transportation.

The decision to walk or bicycle for short trips often depends on time, purpose, or environmental factors (McNeil et al., 2017; Ussery et al., 2017; Simons et al., 2013). Research shows that features of the built environment, such as sidewalks, street lights, protected intersections, traffic and road safety, hills (Gilpin, 2016; US Department of Transportation Federal Highway Administration, 2015; Broach et al, 2012), trees (; Giles-Corti et al., 2011), land-use mix, residential density (Thornton et al., 2016; Dalton et al., 2011; Ewing et al., 2010), and overall walkability (Althoff et al., 2017; Murphy et al., 2017; Wineman et al., 2014), are related to travel behaviors. Additionally, social connectivity can be an important complement to the physical environment (Salahuddin et al., 2016; Hume et al., 2009).

Thus, Safe Routes to School programs include multi-prong approaches to increasing biking and walking school mode share, including physical improvements to the infrastructure around schools, partnerships with local law enforcement to ensure that traffic laws are followed in the school vicinity, and education and encouragement to build a culture of active transportation. Similarly, consideration of built environment factors that promote active transportation and physical activity can be crucial when siting schools (Westford, 2018; US EPA, 2003). This section highlights research demonstrating that street characteristics and the built environment can promote physical activity and active travel behaviors, especially among children to and from school.

Research Highlights:

Walking and Bicycling Mode Share Generally

Low-income populations have the highest rates of walking and bicycling to work (Snyder, 2014).
People of mixed race and Asian Americans have the highest rates of commuting on foot, followed by Latinos at moderately high rates and whites and African Americans at the lowest rates (McKenzie, 2014; McDonald, 2008). [But note that this does not include walking as part of public transit use, which is very prevalent for African Americans.]
Latinos and Native Americans have higher rates of bicycle commuting than whites. Bicycle ridership is growing most rapidly among African Americans and Asian Americans (League of American Bicyclists, 2013).
Well-connected street networks are associated with higher participation in walking (Wineman et al., 2014).
People bicycling consider distance, number of turns, slope, intersection characteristics, traffic volume, and biking infrastructure for commuting and utilitarian trips (Broach et al., 2012).
While people across all racial groups prefer protected bike lanes, more Black and Hispanic people say they would bike more if they could bike with family and friends. This suggests that wider bike lanes enabling people to ride alongside each other would benefit populations of color (Lusk et al., 2017).
People of color and people with lower incomes perceive greater barriers to bicycling and bike share usage, but there is significant interest in and demand for bike share among lower-income people of color (McNeil et al., 2017).
To promote transportation and health in the region, the Nashville MPO improved the built environment to better support walking, bicycling, and public transport use by increasing sidewalk mileage and building more bike lanes and greenways (Meehan et al., 2017).

Mode Share and Safe Routes to School

Since 1969, there has been a dramatic increase in driving children to school as well as a corresponding decrease in walking to school. In 2009, 12.7% of K– 8 students usually walked or biked to school, compared with 47.7% in 1969 (McDonald et al., 2011).
The strongest and most frequently reported barrier to walking to school is distance (Murtagh et al., 2016; Duncan et al., 2016; Van Kann et al., 2015; Gustat et al., 2015; Panter et al., 2010; Larsen et al., 2009; Beck, et al., 2008).
Parents’ perceptions of route safety are an important influence on child participation in biking and walking to school (Panter et al., 2010; Carson et al., 2010; DeWeese et al., 2013; Henne et al., 2014; Ross et al., 2017).
Parental barriers to children’s and adolescents’ active commuting to school are influenced by age, gender, and mode of transport: Parents of children cite traffic volume and dangerous intersections as the main barriers, while parents of adolescents cite distance to school and crime as the main barriers (Huertas-Delgado et al., 2017).
School participation in Safe Routes to School programs has been connected with increases in walking and biking to school (Buckley et al., 2013; Stewart, Moudon, and Claybrooke, 2014; McDonald et al., 2014; Ward et al., 2015; Ross et al., 2017). Safe Routes to School programming may also lead to substantial reductions in pedestrian and bicycle injuries and fatalities for school-age children (5-19 years old) as well as for adults (30-64 years old) (DiMaggio et al., 2016).
In a study in California, children whose school route included a Safe Routes to School construction project such as a sidewalk or crossing improvement were more likely to show increases in active transportation than children who did not pass these projects (15% increase compared to 4%) (Boarnet et al., 2005).
Mode share differs across sociodemographic populations, and participation in walking and biking are important components of health equity. Children from low-income households and children of color, particularly Latinos and African Americans, are more likely to bike or walk to school than whites or higher-income students (McDonald, 2008). Targeted approaches to overcome walking barriers for specific populations (i.e., people of lower socioeconomic statuses, people of color, people with low education levels) can help diminish disparities in walking (Ussery et al., 2017).
Shorter distances, presence of street trees, and lower neighborhood income were associated with increased likelihood of active transport to school in Ontario (Giles-Corti, 2013).
A review of the literature found that walkability, traffic speed/volume, access/proximity to recreation resources, land-use mix, and residential density were the environmental characteristics most consistently associated with overall physical activity for children (Ding et al, 2011).