Objective
Exercising in the presence of a natural environment (termed green exercise) appears to provide additional benefits compared to indoor exercise. We assessed the impact of a green exercise promotional video on the acute psychological benefits of green-outdoor and indoor exercise.

Design
Participants were randomly assigned to one of four groups. Two groups undertook green exercise (with one of these groups watching a green exercise promotional video). The other two groups undertook indoor exercise (with one of these groups watching the promotional video). The green-outdoor and indoor exercise conditions were created to replicate those of a previous study (Rogerson, Gladwell, Gallagher, & Barton, 2016b). The promotional video was designed to highlight benefits of green exercise and was used to manipulate expectations of acute green exercise.

Method
Participants (N = 60) completed 15-min of moderate-intensity cycling, with self-esteem, vigour (dependent variables), and attitudes (manipulation check) assessed pre- and post-activity. Measures of physical activity and green exercise levels were also recorded at baseline.

Results
The findings suggest that green exercise elicits greater psychological benefits than indoor exercise, and those benefits can be increased via expectancy modification. In contrast, the same expectancy modification suppressed the psychological benefits of cycling indoors.

Conclusions
A promotional video can further enhance the affective response to green exercise. This may help to encourage future physical activity participation holding great promise for researchers, practitioners and policy makers.