Application of the theory of planned behavior to fruit and vegetable intake and physical activity of female university students: A mixed methods study

Background: Prevalence rates show that the greatest time of increase in overweight and obesity occurs between the ages of 18 and 29. According to the American College Health Association- National College Health Assessment, 2012 (ACHA-NCHA II), more than 1/3 of students were either overweight or obese. Excess weight in female university students is of concern as they are in their child bearing years. Approximately 41.6% of women start pregnancy as overweight and obese, and more than half of women gain excess weight during pregnancy. Moreover, changes in dietary behaviors and reduction in physical activity often occurs at college. About 94% of students do not get the recommended amount of fruits and vegetables, and more than 50% of students do not get enough physical activity. Examining factors affecting students’ fruit and vegetable intake and physical activity is imperative for interventions to be effective in promoting healthy behaviors and weight control among female university students. Previous studies addressing fruit and vegetable intake and physical activity using behavioral theory have been either conducted based only on using a quantitative study method or investigating these behaviors separately. This was the only known study to examine quantitatively and qualitatively fruit and vegetable intake and physical activity, simultaneously, using the framework of Theory of Planned Behavior (TPB) along with related factors in female university students. Methods: A two-phase explanatory mixed methods design was used. It consisted of collecting qualitative data after a quantitative phase to describe the quantitative data in depth. In phase I, a total of 362 female students participated in an online survey. In phase II, a total of 33 female students participated in five focus group discussions to further explore students’ perceptions on fruit and vegetable intake and physical activity. SPSS was used for the qualitative data analysis and Atlas ti 7.0 was used for the qualitative data analysis. Results: The TPB constructs of attitude, subjective norms, and perceived behavioral control, along with the addition of the weight control status of trying to lose weight, were found to be significant predictors in female university students’ intention to follow the recommendations for fruit and vegetable intake and physical activity, which in turn was a significant predictor of both behaviors. Knowledge of the recommendations was not found to be significant for either fruit and vegetable intake or physical activity. Focus group discussions revealed that students’ beliefs of some of the negative outcomes of meeting the recommendations functioned as barriers to following the recommendations for fruit and vegetable intake and physical activity. Findings also indicated the positive and negative influence of social norms – females with children wanted to be role models; single females felt more negative pressure from friends and others. Overall, students perceived more barriers than facilitators to meet the recommendations for fruits and vegetables than for physical activity. Conclusion: The mixed method approach of the study provided a deeper insight into the influential factors pertaining to fruit and vegetable intake and physical activity among female university students and could be used in further research to develop effective interventions.