Relationships between work and objectively measured sedentary time and physical activity in older adults: a descriptive cross-sectional study

Objectives: This study aimed to objectively assess sedentary time (ST) and physical activity (PA) time during work performed by older adults and investigate the relationship between work and ST/PA in daily life of this population. Methods: Participants were recruited from members of a Silver Human Resources Center and their families and friends. Data for 194 participants (131 workers and 63 non-workers) were included in the analysis. ST/PA during work (workers only) and daily life (all participants) were assessed using an accelerometer. ST/PA during work were defined according to the Japan Standard Occupational Classification. Associations between work and ST/PA in daily life were analyzed by covariance analysis adjusted for confounders. Results: ST during work was longest in clerical workers (35±16.0 min/h). Light-intensity PA during work was shortest in clerical workers (23.2±15.6 min/h), whereas this value was similar among the other occupational classes. Moderate-to-vigorous PA during work was relatively longer in construction and mining workers (15.3±11.9 min/h). Workers were found to have shorter sedentary and longer PA time in their daily life than non-workers. Moreover, workers with longer weekly work hours (≥14 h/wk) were found to have significantly shorter sedentary and longer PA time, and this trend was apparent in blue-collar workers. Conclusions: This study demonstrated objectively assessed ST/PA during work in older adults according to occupational classifications. Furthermore, it investigated the associations between work and ST/PA in daily life and showed the potential contribution of work, particularly blue-collar work, in decreasing ST and increasing PA.