Car use has negative impacts on public health through road traffic accidents, air pollution and physical inactivity. The car’s contribution to the first two of these problems is relatively well recognised and understood, but inactivity is less well understood.
Getting people to walk, cycle and make greater use of public transport therefore has benefits for health. But how do we make it happen? What do we know from the scientific literature about what happens when we change the places where we live in order to influence our choices about how to travel?
There are many ways to intervene to change travel behaviours; some with lots of evidence and some with little or no evidence. I’ve been involved in three studies in this area in the last few years which aim to provide more of that objective evidence.
These studies focus on cycling initiatives, the impact of new routes for walking and cycling, and new transport systems.
Town-wide initiatives to promote cycling
Using routinely collected data from the English Census, we were able to assess the impact of town-wide cycling initiatives in 18 towns. We compare areas which received the initiatives (designated as Cycling Demonstration Towns and Cycling Cities and Towns) to those who didn’t receive the initiatives. All towns used a mixture of capital investment (e.g. cycle lanes) and revenue investment (e.g. cycle training), tailored to each town. We found:
- Among 1.3 million commuters in 18 intervention towns, the prevalence of cycling to work rose from 5.8% in 2001 to 6.8% in 2011.
- These effects were observed across all levels of area deprivation: cycling increased in a relatively inequitable manner.
- Walking to work also increased significantly compared with comparison towns, while driving to work decreased and public transport use was unchanged.
- There was evidence of larger effects in towns placing greater emphasis on workplace cycling initiatives, with this explaining around one third of the observed differences between towns.
High-quality traffic-free routes encourage more walking and cycling
Our analysis from the iConnect study used self-reported data on walking, cycling and physical activity to assess the impact of new, high-quality, traffic-free cycling and walking routes in Cardiff, Kenilworth and Southampton. 1700 residents who lived within 5km of the new routes were surveyed before and after the opening of the infrastructure in 2010, 2011 and 2012. We found:
- After two years, people living near to the new routes increased their total levels of physical activity, compared to those living further away.
- However, initial evaluation after 1 year indicated no effect suggesting that the changes can take time to have an effect.
- There was no evidence that people taking up more walking or cycling over time compensated by reducing their other, recreational, physical activity.
- Results suggested that the new routes not only encouraged people to take up walking but also encouraged those people who were already walking to do more.
- Interviews highlighted a range of reasons why some interventions might have been used more than others, including visibility, design and scale of the new routes, as well as the contrast they presented with existing infrastructure.
A new transport system?
A new state-of-the-art guided busway was constructed in Cambridgeshire and opened in 2011. We used this opportunity to assess its impact on travel in Cambridge using data from annual surveys from 2009 to 2012. Whether or not the busway proved to be a supportive environment for being active on the commute varied for different individuals. Nevertheless, overall:
- Those who lived closer to the busway were more likely to increase their cycling time, and increased the time spent walking or cycling on the commute, even if this was only for part of the journey. Again, we found no evidence of corresponding reductions in recreational activity.
- Commuters who included walking and cycling as part of their journeys through the use of offsite car parks or park-and-ride sites reported an average of 12 minutes of walking or 17 minutes of cycling to and from work per day.
- More than half of the weekly recommended amount of physical activity was achieved through the commute alone, even among those who lived a long way from work.
- Those who lived closer were more likely to report large increases in mode share of active travel trips and a large reduction in share of trips by car over the course of a week.
Implications for policy
- Infrastructure to support active travel is an important part of a strategy for achieving physical activity and health gain in the population.
- Public transport and active travel can coexist rather than compete in a sustainable, health-promoting transport system.
- Active travel can be incorporated into commuting irrespective of the total length of the journey.
- Supporting these ‘mixed mode’ journeys – for example, via park-and-ride sites or bicycle parking at train stations – is an underused strategy.
- Some changes, e.g. improving pedestrian routes, may promote walking but not reduce car trips. Others, e.g. changing parking provision, may be more effective in reducing car trips. This is important when considering impacts on congestion and air quality.
- Travel behaviour is complex, so it is unlikely that small scale environmental changes alone will result in substantial increases in walking and cycling, but it’s an excellent place to start!
- It does not necessarily follow that solutions have to be complex, as long as they are part more comprehensive public health strategies that address many wider factors such as housing, planning and employment policy.
About the author
Jenna is a Senior Research Associate in the Physical Activity and Public Health group at the Centre for Diet and Activity Research (CEDAR). Her current research focuses on examining patterns and determinants of change in physical activity, evaluating environmental and policy interventions and evidence synthesis. If you want to find out more about the work of the Physical Activity and Public Health, please have a look at our webpage.
CEDAR is studying the factors that influence diet and physical activity behaviours, developing and shaping interventions, and helping shape public health policy and practice. It is of one of five Centres of Excellence in Public Health Research funded through the UK Clinical Research Collaboration (UKCRC).
This blog is based on the evidence briefing on this topic. A copy of the evidence brief is available here: http://www.cedar.iph.cam.ac.uk/resources/evidence/eb-15-changing-travel/