Does daylight savings time encourage physical activity?

Background: Extending Daylight Savings Time (DST) has been identified as a policy intervention that may encourage physical activity. However, there has been little research on the question of if DST encourages adults to be more physically active. Methods: Data from residents of Arizona, Colorado, New Mexico, and Utah ages 18-64 who participated in the 2003-2009 American Time Use Survey are used to assess whether DST is associated with increased time spent in moderate-to-vigorous physical activity (MVPA). The analysis capitalizes on the natural experiment created because Arizona does not observe DST. Results: Both bivariate and multivariate analyses indicate that shifting 1 hour of daylight from morning to evening does not impact MVPA of Americans living in the southwest. Conclusions: While DST may affect the choices people make about the timing and location of their sports/recreational activities, the potential for DST to serve as a broad-based intervention that encourages greater sports/recreation participation is not supported by this analysis. Whether this null effect would persist in other climate situations is an open question.