The effect of nature and physical activity on emotions and attention while engaging in green exercise

Green exercise offers the synergistic benefits of both contact with nature and physical activity for humans. This study explored the relationship between nature, physical activity, and well-being, addressing a gap in the research (Hartig et al., 2014). This study further investigated whether and how nature, exercise, or a combination of both produces these benefits. Nature was quantified as the visible greenness rate to measure the continuum from natural to man-made, instead of using a dichotomization. Physical activity was walking and jogging, and the exercise level was quantified to measure the continuum from static to vigorous. Well-being centered on emotions and attention, which have been the most studied responses to green exercise, consistent with Ulrich's (1983) stress reduction theory and Kaplan and Kaplan's (1989) attention restoration theory. Recruiting 116 college students from a technology university in central Taiwan as the participants, this randomized controlled trial conducted field experiments with a pretest-and-posttest design from October 2013 to February 2014. The participants' data on emotions were collected by the Chinese version of the Profile of Mood State short form (Chang & Lu, 2001). Their attention was tested by standardized tests (WMS-III, 1997). The major findings of this study are as follows. Nature explained 17.9% of the variance, while physical activity explained 9.2% of the variance. However, one 15-min bout of physical activity with either low or moderate METs (metabolic equivalents, the energy cost of a physical activity) in a setting with at least 40% visible greenness rate elicited even more benefits, explaining 58.0% of the variance, more than nature alone. Additionally, a low MET physical activity like walking was better than a moderate MET physical activity like jogging to improve attention and emotions without increased fatigue.