Built environment and seasonal variation in active transportation: A longitudinal, mixed-method study in the Helsinki Metropolitan Area

Introduction: Participation in active transportation declines seasonally in urban areas with a distinct cold winter season, resulting in a loss of physical activity and a switch to motorized transport modes during the winter period. Despite the considerable evidence available on the relationship between the objectively measured built environment and participation in active transportation, few studies have examined the influence of the built environment on facilitating year-round active transportation. This longitudinal study examined the potential effect of the built environment on seasonal changes in adults’ walking and cycling for transport. Methods: The study uses data on adults' (18–65 years) active transportation behavior collected in the Helsinki Metropolitan Area, Finland (n 384). A structural equation model including both individual-level and built environment variables was constructed to assess changes in walking and cycling behavior. In addition, a qualitative thematic analysis was performed to identify recurring topics in citizens’ descriptions of their wintertime physical activity behavior. Results: Cycling for transport decreased drastically during the winter season, with many participants ceasing to cycle altogether. Changes in walking for transport were less consistent and showed no significant sample-level difference in the minutes of walking for transport in the baseline and follow-up surveys. The results of the structural equation model indicated that changes in cycling and walking behavior were directly affected by neighborhood residential density and urban structure. Results of the qualitative analysis emphasized the importance of the wintertime maintenance of pedestrian and cycling infrastructure. Conclusions: Our results highlight the multiple ways the built environment may contribute to maintaining summer active transportation behavior during the winter period, ranging from macroscale features of the urban form to the microscale of street-level design and maintenance. This knowledge supports policy and planning efforts to support the continuous use of active transportation modes throughout the year