The circadian activity rhythms for elderly inpatients with stroke or motor diseases in a rehabilitation facility and its relationship to physical activity level.

Disturbances in the circadian activity rhythms (CARs) of inpatients in rehabilitation facilities delay the recovery of physical and mental functions. The purpose of this study is to elucidate the circadian activity rhythms of hospitalized patients in a rehabilitation facilitie using the synthetic periodic regression analysis, and investigate the relationship between their physical activity levels and CARs.An observational study was conducted. A group of thirty-four inpatients participated in the study by wearing wrist-type activity monitors to measure metabolic equivalents (METs). Using synthetic periodic regression analysis, the CARs were analyzed based on the amount of physical activity throughout the day, and the exercise intensity classification of their physical activity was assessed. In the CARs of the inpatients, the mean physical activity level was 1.23 ± 0.09 METs. The maximum amount was 1.36 ± 0.15 METs. The range was 0.30 ± 0.15 METs. The maximum phase time was 11:48 ± 2:31 h. The longer the duration of physical activity over 1.6 METs, the higher the mean, maximum and range of the CARs. Physical activities with a METs level of 1.6 or higher might have an impact on the mean, maximum, and range of circadian activity rhythms in hospitalized patients. Supplementary Information: The online version contains supplementary material available at 10.1007/s41105-023-00488-8.