Patients will go for a silent 60-minute walk in an urban setting. The walk will take place in the months of June, July, August and September between 10:00 to 11:00 am.

Participants will walk in groups of two to three participants accompanied by two research assistants trained in mental health (doctoral students in psychology). The urban walk will be located on Boulevard de la Vérendrye with large arteries with three to four lanes.

Patients will go for a silent 60-minute walk in a nature park setting. The walk will take place in the months of June, July, August and September between 10:00 to 11:00 am.

Participants will walk in groups of two to three participants accompanied by two research assistants trained in mental health (doctoral students in psychology).

The nature walk will take place at Parc Angrignon, an area of 96 hectares, one of Montreal's largest green and biodiverse spaces with a forest of 20 000 trees and a pond surrounded by willow trees.

Walking for 60 minutes as described above

Positive and Negative Affect Schedule (PANAS)

The stroop color word test is a widely used task to assess selective attention and inhibitory control. In the first block of this task (A), color words (red, blue, yellow, green) printed in black ink are presented in random order and participants are asked to read out loud the words. In the second block (B), solid color patches in one of the same four colors are shown and participants name the colors. Finally, in the third block (C), color words are printed in an incongruous ink color and participants must name the ink color (e.g. GREEN [typed in red]; response = red). Participants are asked to complete each block as quickly and accurately as possible and the time to complete each trial is calculated and averaged for each block. An interference score is calculated as followed: C - [(A + B) /2].