The study examines the socioeconomic, demographic and health determinants of physical activity intensity in Russia. Using RLMS-HSE (the Russia Longitudinal Monitoring Survey – Higher School of Economics) data for 2021 and indicators of six levels of physical activity intensity, the authors built ordered probit models and calculated average marginal effects for a set of covariates. The independent variables were selected based on the SLOTH microeconomic model describing individual preferences towards physical activity.The ordered probit regression provided empirical support for Meltzer and Jena's theoretical framework, stating that as income increases, with the pronounced substitution effect, the time spent on physical activity decreases, and the intensity of physical activity rises. In our study, the thesis about an increase in intensity with rising income was confirmed for a subsample of men but not women. For women, the intensity was determined by factors such as multiple morbidity and residing outside of Moscow or Saint Petersburg, which were not significant in the regressions for men.The study resulted in several important conclusions. The intensity analysis showed that physician recommendations regarding the type of physical activity should consider patients' workload. For individuals with a busy schedule, recommended types of exercise that require a long time (for example, walking) are not suitable. At the same time, intense workouts (such as tennis or gym classes) can be built into the schedule. There is a need to develop sports infrastructure at workplaces, allowing individuals to allocate time for classes without bearing additional time and monetary costs associated with travel to the location of workouts. As income increases, exercising near the workplace allows an individual to increase the intensity of physical activity without incurring additional time costs