Background:
Physical activity during incarceration may support physical and mental health. This study aimed to assess physical activity levels, motives for engaging in physical activity, and selected health behaviors among incarcerated individuals.

Material and methods:
The study included 140 incarcerated men from a semi-open prison (n=90) and a closed prison (n=50). The analysis included 94 participants who reported physical activity during incarceration (58 and 36, respectively). Physical activity, health behaviors, and motivation were assessed using an author-designed questionnaire and the Inventory of Physical Activity Objectives (IPAO).

Results:
Gym-based strength training was the most common activity (98.9%), followed by team sports (25.5%), running (20.2%), fitness activities (12.8%), and gymnastics (10.6%). Mean monthly physical activity duration was 23 h 25 min per participant. Daily family contact was more frequent in the semi-open prison (62.1% vs. 13.9%; p<0.001), whereas interpersonal conflicts and stress related to future prospects were more frequent in the closed prison (p=0.001 and p=0.010). No significant differences were found in the IPAO motivational dimensions (all p>0.05).

Conclusions:
Gym-based strength training predominated, while health, physical fitness, and well-being were the main activity objectives. Prison type differentiated selected psychosocial and health-related factors but not the IPAO motivational dimensions. These findings may inform tailored health-promotion programs.