78 Volume 33 • Number 2 • April-June 2010 Research Report ABSTRACT Background and Purpose: Exercise has been shown to improve physical function in frail older adults; however, the effects of exercise may vary with degree of frailty, the format and intensity of the exercise intervention, and level of supervi- sion. This cohort study describes the effects of participation in a 6-week home-based exercise program on measures of phys- ical function as well as exercise-related beliefs, including exer- cise self-efficacy and outcomes expectation, in frail older adults. Methods: Participants were 72 frail older adults who partici- pated in a 6-week home-based exercise program supervised by graduate physical therapy students. Individualized home- based exercises targeted strength, flexibility, balance, gait, and cardiovascular fitness. Physical function was measured at baseline and after completion of the 6-week exercise program using the Functional Fitness Test (Biceps Curl, Chair Stand, 8- Foot Up and Go) and velocity on a 4-m walk. Measures of exercise-related beliefs included the Self-Rated Abilities for Health Practices Scale and Exercise Outcome Expectations. Outcomes: Participation in the 6-week home-based exercise program was associated with improvements in measures of physical function, including an average increase of 3 repeti- tions (35%) on the biceps curl, 2.4 repetitions (59%) on the chair stand, and an average increase of 0.17 m/s (33%) in gait velocity. Average decrease in Timed Up and Go test scores was 5.7 seconds (26%). Scores for exercise-related beliefs also improved (self-efficacy average increase was 7 points [40%], and average increase in outcome expectations was 3 [47%]). Discussion: A supervised 6-week, multidimensional home- based exercise program was safe and associated with improvements in physical and exercise-related belief outcome measures in this cohort study of frail older adults. Key Words: frailty, home-based exercise, physical function, psychological function (J Geriatr Phys Ther 2010;33:78-84.) INTRODUCTION Frailty has been described as a state of increased risk or vul- nerability, which is most often attributed to reduced physi- ologic reserve and a decrease in homeostatic capability for withstanding stressors. 1,2 Researchers have estimated that 40% of adults 80 years and older may be classified as frail. 3 Among older adults, frailty is associated with adverse health outcomes, including mortality, disability, falls, and the need for long-term care. 1 Although there is no universal agreement about the critical dimensions of frailty, core fea- tures include weight loss and sarcopenia, muscle weakness, reduced endurance and energy, slow movement, and low physical activity level. 2 These core features have been used to establish a continuum of frailty; with older adults exhibiting 3 or more core features categorized as fully frail, while those with 1 to 2 features classified as prefrail or intermediate frailty. 2 Frailty appears to be a dynamic process, rather than a static state, with transitions occurring between nonfrail, prefrail, and frail states. 2,4,5 Exercise has been shown to improve physical function in frail older adults; however, the effects of exercise may depend on a number of factors, including the degree of frailty, the format and intensity of the exercise intervention, and level of supervision. Several studies have reported that exercise was more effective in improving physical function in adults classified as being intermediately frail compared with those who were frail, 6,7 whereas others have reported positive effects of exercise among frail older adults. 8-10 Among relatively healthy older adults, home-based exercise programs have greater adherence rates than group-based community programs 11,12 and are effective in improving functional performance and balance in functionally impaired elders. 11 Studies by King and colleagues 12,13 have shown that low-intensity home-based exercise programs were as effective as higher intensity programs in improving fitness among sedentary but healthy adults 50 to 65 years of age. Professional supervision also appears to play an important role in exercise programs as well. Supervision by a healthcare professional in both home-based 11 and class- based programs 14 demonstrated more positive health out- comes than in a comparable nonsupervised program. 11,14 Finally, it has also been shown that perceptions regarding the benefit of exercise and perceived ability to perform exer- cise can influence the outcome from training. 15 Few studies have systematically examined the effects of a supervised The Effects of a Home-Based Exercise Program on Physical Function in Frail Older Adults Patricia Noritake Matsuda, PT, DPT; Anne Shumway-Cook, PT, PhD, FAPTA; Marcia A. Ciol, PhD Department of Rehabilitation Medicine, University of Washington, Seattle. Address correspondence to: Patricia Noritake Matsuda, PT, DPT, Department of Rehabilitation Medicine, Division of Physical Therapy, University of Washington, 1959 NE Pacific St, Box 356490, Seattle, WA 98195 (pmatsuda@u.washington.edu).