1. Faculty of Health Sciences and Sport, University of Stirling , Stirling, FK9 4LA , UK
2. Physical Activity for Health Group , Department of Psychological Sciences and Health, , Glasgow, G1 1QE , UK
3. University of Strathclyde , Department of Psychological Sciences and Health, , Glasgow, G1 1QE , UK
4. MRC/CSO Social and Public Health Sciences Unit , School of Health and Wellbeing, , Glasgow, G12 8TB , UK
5. University of Glasgow , School of Health and Wellbeing, , Glasgow, G12 8TB , UK
6. School of Pharmacy and Life Sciences, Robert Gordon University , Aberdeen, AB10 7GJ , UK
7. Institute of Applied Health Sciences , School of Medicine, Medical Sciences and Nutrition, , Aberdeen, AB25 2ZD , UK
8. University of Aberdeen , School of Medicine, Medical Sciences and Nutrition, , Aberdeen, AB25 2ZD , UK
9. Strathclyde Institute of Education, University of Strathclyde , Glasgow, G4 0LT , UK