This study investigated differences in the type of and number of perceived barriers to engagement in physical activity experienced by adult women and men in the same geographical area, the relationship between the experienced barriers and stages of change in relation to exercise behavior, and identified barriers related to reported engagement in leisure-time physical activity. Data were obtained from a population study by the National Institute of Public Health in two counties during 2000-2001. The sample consisted of 2709 females and 2212 men in the age groups 75, 60, 45, 40 and 30 years. Questionnaires measured barriers to engagement in physical activity, engagement in physical activity and readiness for engaging in physical activity (stages of change). Multivariate analyses of variance demonstrated significant age and gender differences in the perceptions of barriers at the various stages of change. The logistic regressions [estimated odds ratios (OR)] demonstrated that low scores for affective/cognitive and practical barriers were significantly associated with higher OR for engagement in physical activity for women, and low-priority barriers and lower age were associated with higher OR for being physically active for men. The information from this study should be valuable for designing and tailoring both motivational strategies and interventions to fit targeted groups.