Relationship Between Air Quality and Outdoor Exercise Behavior in China: a Novel Mobile-Based Study.

PURPOSE: Based on data collected from an exercise app, the study aims to provide empirical evidence on the relationship between air quality and patterns of outdoor exercise in China.

METHODS: Objective outdoor exercise data spanning 160 days were collected from 153 users of an exercise app, Tulipsport in China. Each exercise mode (running, biking, and walking, respectively) was organized into five air quality categories based on Air Quality Index (AQI): excellent, good, mild pollution, moderate pollution, and serious pollution. Key parameters of each app user were calculated and analyzed: the total number of exercise bouts, the average duration, and the average distance of each exercise mode in each air quality category.

RESULTS: Multivariate analyses of variance indicate that the users were less likely to participate in outdoor running, biking, and walking (F = 24.16, p < .01, Wilk's Λ = 0.64) as levels of air pollution increased. However, there is no difference in terms of average distance and duration of exercise across different air pollution categories.

CONCLUSIONS: People's participation in outdoor exercise is impeded by air pollution severity, but they stick to their exercise routines once exercise is initiated. Although people should protect themselves from health damages caused by exercising under pollution, the decreases in physical activity associated with air pollution may also pose an indirect risk to public health. The interactive relationship between air quality, exercise, and health warrants more empirical and interdisciplinary explorations.