Psychological determinants of physical activity in Japanese female employees

To understand how psychological characteristics influence adoption and maintenance of physical activity/exercise, we conducted a cross-sectional study among Japanese employees based upon the idea of stages of behavior modification. The study population consisted of 719 employees (male, 396, female, 323) from five medium-sized manufacturing companies (50-200 employees) in Okayama Prefecture, Japan. The female response rate was 67.5% (n=218), among which 201 eligible female subjects (62.2%) were analyzed. The study questionnaire included demographic characteristics, physical activity/exercise measures, self-efficacy measures, and perceived benefit and barriers scales. Participants were asked to select the items that best described their current physical activity/exercise level from an 8-item questionnaire, and we converted their answers to the 5 stages of change according to a transtheoretical model of behavior change. Perceived benefit and barrier scales were classified into 7 factors (4 benefits and 3 barriers) by factor analyses. The relationship between psychological determinants and the stage of physical activity/exercise was examined by one-way analysis of variance. Only 10% of the subjects had moderate physical activity (in the action and maintenance stages) regularly. We found that self-efficacy, "weight control benefit", "physical barrier" and "time barrier" were psychological determinants of physical activity/exercise stages in female employees, and especially there was a consistent relationship between self-efficacy and the stage of physical activity/exercise. Our data suggest that health education for Japanese female employees requires that health professionals should provide support for strengthening self-efficacy, show practical ways to increase physical activity in daily life, and provide broad and accurate information showing that physical activity/exercise have a good effect on health.