Both the ability and the opportunity to move about constitute essential requisites to older adults' independent living and societal participation. The ability-that is the fundamental physical capacity-to move is a basic human need and essential to personal health (e.g., Heikkinen et al., 1992; U.S. Department of Transportation, 2003). In that sense, declining mobility has been understood predominantly as a physical health and geriatric issue. For decades, a broad range of research has been conducted to understand, among other things, the increasing decline in mobility performance, including decrements in sensory abilities and sensorimotor integration, loss of motor control and voluntary strength, slowing motor action and speed of processing. shrinking range of motion and flexibility, and decreasing ability to stabilize