Exercise participation is linked to mental health and wellbeing. However, we need to identify optimal settings for promoting exercise-associated wellbeing outcomes, and for promoting exercise adherence. The literature suggests environmental settings may be important. The aim of this thesis was to rigorously test influences of environmental settings on exercise-related wellbeing outcomes. These over-arching research questions guided the experimental chapters: (i) is there an optimal green exercise environment for promoting wellbeing? (ii) When exercise is controlled, are findings consistent with previously reported psychological outcomes? (iii) Do environmental settings influence social outcomes of exercise or intentions to repeat exercise behaviours? Via field-based sampling, Chapter 3 found large proportions of affective benefits were universally obtainable across four typical green exercise environments, and suggested that the processes component of green exercise warranted further investigation; however, this method lacked control. Chapter 4 used laboratory-based methodology to control exercise and isolate the visual environment; consistent with both theory and previous research, nature environments facilitated wellbeing-related attention restoration. However, this method did not provide an accurate multisensory experience, therefore lacking ecological validity. Chapter 5 investigated methodologies for controlling the exercise component, comparing wellbeing-related outcomes of indoor versus outdoor exercise. This was important because previous research had not rigorously controlled exercise, therefore potentially confounding its findings. Results for environment-related exercise differences and affective outcomes were inconclusive. Chapter 6 merged laboratory-based methods with the indoor versus outdoor exercise paradigm, ensuring control and ecological validity. Environmental setting did not influence perceived exertion or mood; green settings promoted attention restoration and social interaction; for green exercise, social interaction predicted exercise intentions. Green exercise promotes wellbeing improvements; environmental influences on affective outcomes may be contributed to by differences in exercise performed. Independent of exercise differences, green environments promote attention restoration and social interaction during exercise, which may in turn influence exercise intentions.