Objective:To explore the correlation between weekend moderate-to-vigorous physical activity(MVPA), weekday sedentary behavior(SB)and the risk of frailty in the elderly population monitored by wearable devices, and to provide a scientific basis for lifestyle interventions for frailty in the elderly.Methods:This study was based on the data of the UK Biobank from 2013 to 2015.A cross-sectional study design was adopted, and 33, 212 elderly people aged 60 and above with complete physical activity monitoring data were selected.The Frailty Index(FI)constructed by the deficit accumulation method was used to assess the frailty status.The correlation between the combined effect of weekday SB and weekend MVPA and the frailty status was analyzed, and the differences between genders were explored.Results:There were significant differences in physical activity indicators among the elderly with different frailty statuses.As the degree of frailty increased, the MVPA-related indicators showed a downward trend, while the weekday SB time gradually increased.There were sex differences in physical activity patterns and frailties.Compared with women, men had longer SB time on weekdays, lower metabolic equivalent of weekly MVPA consumption, and higher MVPA time on weekends, but the frailties index of women was slightly higher than that of men.After adjusting for confounding factors, the frailty risks for men and women in the subgroup with the lowest weekday SB and the highest weekend MVPA duration decreased by 46.9% and 59.8%, respectively( P<0.001)when compared to the highest-risk group. Conclusions:Based on the monitoring data from wearable devices, elderly individuals who reduced their SB time during weekdays and increased their MVPA time on weekends were associated with a lower risk of frailty, especially among women; which providing a new perspective for lifestyle-based intervention strategies for frailty among the elderly.

Objective:To explore the correlation between weekend moderate-to-vigorous physical activity(MVPA), weekday sedentary behavior(SB)and the risk of frailty in the elderly population monitored by wearable devices, and to provide a scientific basis for lifestyle interventions for frailty in the elderly.Methods:This study was based on the data of the UK Biobank from 2013 to 2015.A cross-sectional study design was adopted, and 33, 212 elderly people aged 60 and above with complete physical activity monitoring data were selected.The Frailty Index(FI)constructed by the deficit accumulation method was used to assess the frailty status.The correlation between the combined effect of weekday SB and weekend MVPA and the frailty status was analyzed, and the differences between genders were explored.Results:There were significant differences in physical activity indicators among the elderly with different frailty statuses.As the degree of frailty increased, the MVPA-related indicators showed a downward trend, while the weekday SB time gradually increased.There were sex differences in physical activity patterns and frailties.Compared with women, men had longer SB time on weekdays, lower metabolic equivalent of weekly MVPA consumption, and higher MVPA time on weekends, but the frailties index of women was slightly higher than that of men.After adjusting for confounding factors, the frailty risks for men and women in the subgroup with the lowest weekday SB and the highest weekend MVPA duration decreased by 46.9% and 59.8%, respectively( P<0.001)when compared to the highest-risk group. Conclusions:Based on the monitoring data from wearable devices, elderly individuals who reduced their SB time during weekdays and increased their MVPA time on weekends were associated with a lower risk of frailty, especially among women; which providing a new perspective for lifestyle-based intervention strategies for frailty among the elderly.