Introduction Sedentary behaviour (SB) is a distinctive form of human behaviour that should not be considered the endpoint of the physical activity (PA) continuum. Hence, SB and PA might work independently in relation with mental health (MH). Investigating these relationships may inform public health initiatives targeting MH promotion.
Methods 6720 adults aged 24–65 years from the Belgian National Health Survey provided data on SB and PA via the IPAQ, and on MH via the GHQ12 and the SCL-90-R. Multiple logistic regression analyses examined associations between SB and five MH problems, controlling for PA and other confounders. Further analyses explored variations across gender, age, SES, and participation in recommended moderate- and vigorous-intensity PA.
Results In the total sample, SB was positively associated with feelings of depression OR=1.406, 95% CI [1.157 to 1.709], anxiety OR=1.523, 95% CI [1.217 to 1.905], and symptoms of somatisation OR=1.401, 95% CI [1.134 to 1.732]. These MH problems were significantly more present among individuals who sat over 2100 min/week (controlled for PA), indicating potential independent detrimental MH outcomes of SB. Further, these positive associations existed independent from gender and age, in the lower SES category, and among all individuals who did not fulfil one PA recommendation. Fulfilment of either one PA recommendation, and high SES seemed protective, with the potential MH protective effects of recommended PA approaching the MH protective effects attributed to high SES.
Conclusion While it is important to encourage both increases in PA and reductions in SB, from the perspective of MH, increasing PA may represent the priority, since PA seems protective against the independent detrimental MH outcomes of SB.