Improving transport infrastructure to support walking and cycling on the journey to and from work – active commuting – could help to promote physical activity and improve population health. However, there is limited evidence from intervention studies to guide policy and practice. We therefore took the opportunity presented by a ‘natural experiment’ to conduct a quasi-experimental study of the effects of new transport infrastructure on travel behaviour, physical activity and related wider health impacts among commuters.
The study was based around the opening of the Cambridgeshire Guided Busway, the longest guided busway in the world. Cambridge lies 80 km north of London and has a distinct cycling culture related to its flat topography, its large student population and the traffic congestion in its historic city centre. The busway links towns and villages to the north-west of the city with the Science Park, the city centre and the Biomedical Campus on the southern fringe. Buses run on a completely segregated guideway along most of the route, and a new high-quality traffic-free path for pedestrians and cyclists is provided alongside the guideway.