Contribution of house and garden work to the association between physical activity and well-being in young, mid-aged and older women.

OBJECTIVE Although physical activity occurs in leisure, transport, occupational and domestic domains of life, the contribution of house and garden work (HGW) to the association between total physical activity and well-being is not clear. The aim was to describe the contribution of HGW to total physical activity (TPA) in association with well-being in younger, mid-aged and older women. DESIGN Younger (25-30 years), mid-aged (50-55 years) and older (76-81 years) participants in the Australian Longitudinal Study on Women's Health completed a mailed survey with questions about leisure, transport and house and garden activities. Well-being was assessed using the physical and mental components scores of the SF-36. Cross-sectional associations between the physical activity variables and well-being were modelled using General Additive Modelling. RESULTS Correlations between HGW and leisure/transport activity (LTA) were low (r<0.3, p<0.001). Positive curvilinear associations were found between LTA and physical and mental well-being in all three cohorts, and between HGW and physical and mental well-being in mid-aged and older women. In the younger women, an inverse relationship was found between HGW and well-being. When HGW and LTA were summed (TPA), the associations between TPA and well-being were attenuated compared with those for LTA alone and well-being. CONCLUSIONS In mid-aged and older women, relationships between HGW and well-being were similar to, but weaker than seen for LTA and well-being. In young women, well-being declined with increasing HGW. Summing HGW to LTA led to attenuated relationships, suggesting that domains of physical activity should not be summed when studying relationships with well-being.