Dissertation: 17.2.2017 Walking, physical activity, and life-space mobility among older people (Tsai)
Autonomy in mobility is a central component of active ageing. Life-space mobility describes where, when, and how an individual reaches desired destinations. Walking, an important form of physical activity among older people, is a prerequisite for engaging in daily activities. This study explored the cross-sectional and longitudinal relationships between physical activity and life-space mobility. The associations of walking with reasons for going outdoors in different life-space areas, living arrangements, and environmental barriers to mobility were also examined.
Data from two larger studies were used: the Life-Space Mobility in Old Age (LISPE) accelerometer substudy (n=174, median age 79.7) and Screening and Counseling for Physical Activity and Mobility in Older People (SCAMOB) (n=657, median age 77.0). Participants were community-dwelling older people living in Central Finland. Physical activity and step count were measured by an accelerometer (Hookie, tri-axial, “AM20 Activity Meter”) for 7 days. Life-space mobility was assessed with the University of Alabama at Birmingham Study of Aging Life-Space Assessment. Reasons for going outdoors, walking for errands and environmental mobility barriers were self-reported.
The cross-sectional analyses showed that life-space mobility correlated with objectively measured physical activity. Over the two-year follow-up, a lower step count and less moderate-intensity physical activity at baseline preceded a significantly steeper decline in life-space mobility. In old age, a higher amount of walking activity was associated with going outdoors for shopping or walking for exercise, living alone, and perceiving fewer environmental mobility barriers.
This study indicates more time spent walking outdoors and the accumulation of moderate-intensity physical activity may help to maintain higher life-space mobility, a correlate of good quality of life. In promoting walking activity among community-dwelling older people, both individual and environmental factors should be taken into account.
Keywords: Life-space mobility, accelerometer, physical activity, walking, mobility