Background. Poor health / medical contraindications are one of the most commonly declared barriers to physical activity (PA). The aim of the study is to do a quantitative assessment of this barrier in adult Poles, with a particular emphasis on incidence and accumulation in different demographic and socio-economic backgrounds. Material and methods. A representative sample of Poles aged ≥50 years, declaring sporadic PA, or none (4253 persons) was examined. To assess the frequency of health indications / medical contraindications as the primary barrier to PA, a statistical analysis was done. The impact of individual variables on individual declarations was assessed using logistic regression. Results. Poor health / medical contraindications are the second (25.0%) barrier to PA, after the age factor (26.6%). The likelihood that bad health is declared in people with lower education increases more than 2-fold (ceteris paribus) with regard to those with higher education. As for working people, it is more often evidenced (7-times) in those incapable of working than in the retired ones (4 times). Living in rural areas reduces the chances of pointing to a health barrier by 24%. Although the chances of declaring health as the barrier increase with age, in the oldest (with all other indicators ceteris paribus) it is relatively less likely to be identified, which might suggest that the elderly consider a ge itself as a barrier to activity rather than poor health. Conclusions. It is necessary to improve health education in adult Poles regarding a conscious lifestyle design, understanding diseases and honest self-assessment of one’s health. It is essential to be aware of the physiological symptoms of physical effort, the role of PA both in maintaining and improving one’s health and supporting treatment. It is particularly essential to involve in the undertaking health professionals, especially doctors, because of their knowledge and social prestige.