Introduction and objective:
Relief from routine physical tasks leads to increasingly sedentary behaviour (SB) – a risk factor for non-communicable chronic diseases. It is necessary to gather interdisciplinary knowledge about the possibilities of its reduction. The aim of the study is to analyse SB and its conditions among Polish white-collar and blue-collar workers.

Material and methods:
The study is based on data retrieved from a large-scale survey used to collect information on the physical activity of Polish society. The data were gathered on a representative sample of Poles at working age ≤69 years old in 2017 (n=2,131). The Polish long version of the International Physical Activity Questionnaire (IPAQ-LF) was used. Statistical inference was based on non-parametric (U-Mann Whitney and Kruskal-Wallis) tests.

Results:
The total average sitting time of the respondents was 1,958.5 min./week. White-collar workers are more likely (p 7.5 h/day (20.2% vs 9%), and blue-collar – ≤4.5 h/day (56.5% vs 42.1%). On a weekday, white-collar workers are sitting significantly longer. The bigger the place of residence, the longer the time sitting in both groups (p=0.000). The time of sitting on a non-working day does not differ among white-collar (221.4 min./day) and blue-collar workers (230.4 min./day). White-collar workers sit longer in vehicles (p <0.0001): 482.4 vs blue-collar workers 326.8 min./week.

Conclusions:
The results suggest a change in Polish recommendations regarding the SB. Blue-collar and white-collar workers need support from the State policy in this matter and need guidance from pro-health programmes. It is necessary to intensify coherent, interdisciplinary and intersectoral activities aimed at creating environments that effectively counteract SB in the place of work and residence, especially in the larger agglomerations.