Background: Interventions to promote physical activity frequently target hypothesized mediators of change, but these might be affected by a person's awareness of their own physical activity behavior. The paper aims to characterize a high-risk population by levels of awareness and to study associations between awareness and selected personal, behavioral and psychosocial factors.
Methods: Data were collected on physical activity behavior, physical activity awareness, behavioral and psychosocial factors and anthropometry cross-sectionally at 6-month follow-up in a physical activity promotion trial. Awareness was assessed by comparing dichotomous self-rated physical activity with achieving activity levels according to international guidelines. Four groups were distinguished: 'Realistic Active', 'Realistic Inactive', 'Overestimator', and 'Underestimator'. Data were analyzed with ANCOVA, correcting for previous interventions and current physical activity level.
Results: Of 632 participants (mean age: 56.3 years), 321 were inactive, 61.4% of whom rated themselves as active ('Overestimators'). Compared to 'Realistic Inactives', 'Overestimators' were older, less likely to be smokers or to intend to increase their physical activity level, and had a lower body mass index. Furthermore, 'Overestimators' had similar scores to the 'Realistic Actives' on the psychological factors, but differed significantly from the 'Realistic Inactives'.
Conclusion: People who overestimate their physical activity level appear to be healthier than people who aware of their low activity level. Overestimators also scored more positively on various psychosocial factors and were also less likely to intend to change their physical activity behavior, making awareness a potential barrier in physical activity promotion. Physical activity promotion strategies might include interventions with a focus on increasing awareness in this hard to reach population.