Residential greenness, physical activity and mental health in Growing-up parents. Is mediation or moderation what are we talking about?

Residential greenspace is thought to contribute to a better mental health through, among others, the promotion of physical activity (e.g. walking or jogging). This means that people having parks near home, would engage in physical activity to a greater extent than people with no parks nearby and therefore show a stronger mental health. However, it is also plausible that PA-oriented people (e.g. enjoying the green outdoors) get more mental health benefits from near green spaces than more “indoor oriented” people because they visit them more frequently for PA purposes. The objective of this study is to discern if both green-PA hypotheses are confirmed with Growing-up data and which one is more compelling.