Gender differences in influences of perceived environmental and psychosocial correlates on recommended level of physical activity among New Zealanders

Objectives: Using the data derived from a nationally representative mail survey conducted in New Zealand, this study firstly considered whether psychosocial factors influence physical activity (PA) participation independent of environmental factors. The second purpose was to examine whether one psychosocial dimension exerted a stronger influence on PA than others, and if the relative influences of these factors vary between men and women. Design: A cross-sectional population-wide study. Methods: Adults aged 16 years and older (n = 8,163) were classified as 'sufficiently active' if they had accumulated at least 150 min over five or more days per week of walking, moderate or vigorous-intensity PA. Summary scores for perceived availability of facilities supportive of PA, self-efficacy, social support, extrinsic motivation and health outcome expectancies were computed and three levels created for each variable (e.g., low, moderate and high self-efficacy). Sufficient PA was regressed on psychosocial and environmental factors, adjusting for potential confounders in a series of logistic regressions. Results: Having high PA self-efficacy impacted substantially on the relationships with PA for men (OR: 5.93, 95% CI: 4.76-7.40) and women (OR: 5.58, 95% CI: 4.49-6.92), followed by social support for PA, but only among women (OR: 2.12, 95% CI: 1.70-2.64). After controlling for socio-demographic variables and psychosocial factors, having high availability of facilities supportive of PA (OR: 1.39, 95% CI: 1.12-1.72) was associated with sufficient PA among men. Among women, no significant relationships were observed between perceived availability and sufficient activity after adjusting for psychosocial factors. Conclusions: These findings provide insight into the relative contribution of perceived environmental and psychosocial factors on PA participation, indicating that these factors are of differential importance across gender. The results affirm the importance of taking into account gender differences when designing interventions aimed to address psychosocial factors for increasing PA. (C) 2006 Elsevier Ltd. All rights reserved.