The U.S. Department of Health and Human Services (1990) has specified as a key objective the reduction of disability in the performance of activities of daily living (ADL) for persons over the age of 65 years. Many ADL involve combinations of muscular strength, muscular endurance, and flexibility, three components that together have been referred to as "muscular fitness." The capacity of the elderly to remain functionally independent, therefore, may depend less on cardiovascular fitness, which has traditionally been the focus of health related fitness research, than on these components of muscular fitness. This review addresses the issue of muscular fitness and disability in the elderly by considering three questions: Is muscular fitness associated with ADL performance? Can muscular fitness be improved with exercise training? Do improvements in muscular fitness improve ADL performance? Answers to these questions will have important implications for future research and program implementation. Although initial findings are promising, more data are needed on the effect of muscular fitness on functional independence and quality of life in the elderly.
The authors are with the Stanford Center for Research in Disease Prevention, Stanford University School of Medicine, 730 Welch Road, Suite B, Palo Alto, CA 94304-1583.