Is sitting bad for your mental health?

Sedentary behaviors are any waking activity characterized by energy expenditure ≤ 1.5 metabolic equivalents and sitting or reclining posture. People currently spend a substantial amount of time in sedentary behaviors and this has been linked to poor physical health, independent of physical activity (PA) levels. Little is known about associations of sedentary behaviors with mental health and quality of life. Purpose: To explore the association between objectively measured sedentary behavior and perceived mental health and quality of life. Methods: 42 adults (19M, 23F); mean age 38yrs (range 18-67); BMI 24.8kg/m2 (range 18.7-33.8) wore an activPAL monitor 24h/day for 1 week and completed the Hospital Anxiety and Depression Scale (HADS) and SF-12 Health Survey. The activPAL monitor measures posture and classifies an individual’s activity into time spent sitting/lying, standing and stepping. Sedentary time was defined as time spent sitting/lying by subtracting participant recorded sleep time from activPAL recorded sitting/lying time. Average weekday and weekend day sitting/lying time was computed. Differences in HADS and SF-12 subscale scores were examined across sitting/lying groups (Low less than 8hrs/day, Medium 8-10hrs/day, High more than 10hrs/day) using ANCOVA with a measure of PA (step count) included as a covariate. All tests were conducted at p