Longitudinal analysis of sitting time and impact on wellbeing and quality-of-life of sedentary workers.

Sitting time (ST) in the occupational domain has been linked to reduced wellbeing and quality-of-life. However, studies investigating the impact of reducing ST in these outcomes are scarce. An ancillary analysis using data from a RCT containing a 6-month sit-stand desk-based intervention, evaluated workers' changes in ST (objectively measured), and subjective wellbeing and quality-of-life. Two groups were created based on changes in ST. Independent and paired-sample T-tests were used to evaluate the differences between and within groups, and analysis of covariance (ANCOVA) was conducted to evaluate the effects of ST reduction in the outcomes. Our analyses indicated that 13 participants out of 38 reduced ST (-72min/day [±40.0; p < 0.001], while 25 participants slightly reduced or increased ST (+36.7 min/day [±40.3; p < 0.001]). Both groups had an improvement in quality-of-life scores, but only those who reduced ST improved subjective wellbeing (p = 0.028). Despite these results, no time*group interaction was found.