Association of respiratory function with physical performance, physical activity, and sedentary behavior in older adults.

[Purpose] The associations between respiratory function, physical performance, physical activity, and sedentary behavior in older adults remain to be elucidated. This study aimed to investigate the associations of lung volume and respiratory muscle strength with physical performance, physical activity, and sedentary behavior in older adults. [Participants and Methods] In 62 ambulatory community-dwelling older adults, lung volumes (forced vital capacity and forced expiratory volume in 1s), respiratory muscle strength (maximum inspiratory and expiratory muscle pressures), physical performance (Timed Up and Go test and 30 s chair stand test), physical activity (steps and locomotive and non-locomotive physical activity), and sedentary behavior (percent sedentary time) were assessed. [Results] The percent sedentary time, 30-s chair stand test performance, and non-locomotive moderate-to-vigorous physical activity were independently associated with forced vital capacity, maximum inspiratory pressure, and maximum expiratory pressure, respectively. [Conclusion] The preliminary findings suggest that lung volumes and respiratory muscle strength may be differently affected by physical performance, physical activity, and sedentary behavior in ambulatory older adults.