Long-term Trends In Step Counts Among Non-working Adults: National Health And Nutrition Survey Japan 2001-2019

PURPOSE: Previous studies have reported that the number of steps among Japanese workers has decreased since 2000, and that this decrease may be attributed to a decrease in physical activity at work. On the other hand, by identifying trends in the number of steps among non-workers, changes in physical activity in daily life outside of work can be estimated. The purpose of this study is to examine long-term trends in daily step count in a nationally representative sample of Japanese non-workers. METHODS: We analyzed individual data from the National Health and Nutrition Surveys Japan 2000-2019. A total of 18,154 non-working adults (men 16.1%, aged 18-59 years) who participated in a one-day pedometer survey (AS-200, YAMASA) were included in this study. Non-workers were homemakers (n = 13,370, men 1.0%), students (n = 2,266, men 54.6%) and unemployed individuals (n = 2,518 men 62.0%). The mean difference in age-adjusted steps between 2001-2010 and 2011-2019 was estimated by analysis of covariance. RESULTS: Mean age-adjusted step counts per day did not differ by gender among the unemployed (men 5108, women 4,836) and students (men 7,572, women 7,635), whereas women took more steps than men among homemakers (men 5,672, women 6,460). Compared to 2001-2010, the number of age-adjusted steps per day in 2011 and 2019 among unemployed men and women decreased significantly (men: -752 (95%CI: -1170, -334), women: -517 (95%CI: -921, -113)), but not among students (men: -305 (95%CI: -783, 172), women: -401 (95%CI: -891, 88)). For homemakers, there was a significant decrease for women, while there was no change for men (men: -668 (95%CI: -1817, 481), women: -790 (95%CI: -906, -674)). CONCLUSIONS: Over the past two decades, the age-adjusted number of steps among Japanese non-workers, excluding students, has declined for both men and women, suggesting that physical activity have declined in daily life outside of work. Supported by the Japanese Health and Labor Sciences Research Grant 22FA1005 and 22FA2001