The elderly population in the United States has grown from 3 million in 1900 to 39 million in 2008, with a projected growth to almost 90 million by 2050 [1
]. Older age has been associated with increased prevalence of chronic diseases [2
] and sensory impairments [3
]; changes in cognitive processing time [4
]; alterations in balance and stamina [5
]; increases in falls, fall-related injuries, and death [5
]. Mobility can mitigate some of the negative health consequences of aging and promote social interactions critical to aging successfully; therefore, it is essential to create environments that encourage safe mobility.
Unfortunately, current research indicates that many older Americans live in communities that hinder rather than facilitate safe mobility. Analysis of data from the Centers for Disease Control and Prevention's (CDC's) 2002 National Health Interview Survey indicates that the largest proportion of persons with disabilities, including age related, reported that their most frequent barriers to community participation included unsuitable building design (43%), transportation (32%), and sidewalks/curbs (31%) [7
]. Similarly, a recent AARP study found that between 40% and 50% of seniors reported inadequate sidewalks in their neighborhoods and an inability to cross main roads safely near home [8
Beginning in 2011, 10,000 people will turn 65 every day, and this rate of achieving senior status will continue for 20 years [9
]. Moreover, physical activity rates and community engagement level off or decline with increasing age—potentially bringing on declines in health [1
]. These patterns could have a significant impact on healthcare and long-term care in the future, since the use of formal and informal health-related services is strongly correlated to increasing age [10
]. If we as a society are to respond successfully to these implications, as well as others, we must ensure that the aging population remains healthy, vital, and engaged in their communities as long as possible.
CDC's healthy aging research network (HAN) defines healthy aging as “the development and maintenance of optimal physical, mental and social wellbeing and function in older adults. It is most likely to be achieved when physical environments and communities are safe, and support the adoption and maintenance by individuals of attitudes and behaviors known to promote health and well-being; and by the effective use of health services and community programs to prevent or minimize the impact of acute and chronic disease on function” [11
]. These statements indicate that in order to maintain optimal health during aging, an individual must be able safely to take advantage of health-promoting behaviors such as physical activity and social interaction, and the individual must be able to access health-promoting resources such as nutritional food, clinical preventive services, and other medical care. Exercising such behaviors and gaining access to such resources is difficult, if not impossible, if an individual's mobility is seriously impaired.
Avoiding mobility impairment during aging is not necessarily something that an individual can accomplish alone, however. The World Health Organization's International Classification of Functioning, Disability, and Health (ICF) defines disability, including such functional limitations as mobility impairment, as an outcome of interactions between health conditions (diseases, disorders, and injuries); contextual factors—such external environmental factors as architectural characteristics, legal and social structures, and so forth; internal personal factors, including age, coping styles, and other factors that influence how disability is individually experienced [12
The purpose of this paper is to describe a model of the different levels at which the physical environment can influence mobility and to list some of the key individuals or professions that can be most effective in helping to create livable communities that promote optimal mobility throughout the lifespan.