M. Araban - “Social Determinants of Health Research Center” and “Department of Health Education and Promotion, Public Health School”, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
Kh. Jafarpour - “Social Determinants of Health Research Center” and “Public Health School”, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
A.A. Arastoo - “Social Determinants of Health Research Center” and “Department of Health Education and Promotion, Public Health School”, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
Z. Gholammnia-Shirvani - Department of Medical Education Development, Education Development Center (EDC), Babol University of Medical Sciences, Babol, Iran
A. Montazeri - Health Metrics Research Center, Iranian Institute for Health Sciences Research (ACECR), Tehran, Iran
A.A. Haeri-Mehrizi - Health Metrics Research Center, Iranian Institute for Health Sciences Research (ACECR), Tehran, Iran

Aims: Physical inactivity and a sedentary lifestyle increase the risk of all-cause mortality. This study aimed to assess the impact of a theory-based education on PA among female health volunteers in Iran by applying the Theory of Planned Behavior. Materials & Methods: This randomized controlled trial was conducted on female health volunteers in Shushtar, Iran, from March to December ۲۰۱۶. One hundred ten participants were selected by purposive sampling, and they were randomized into intervention and control groups based on a ۱:۱ ratio in a single block.  The intervention included three educational sessions and a walking program. A multi-section questionnaire containing items on TPB constructs, the international physical activity questionnaire, and the physiological cost index (PCI- an objective measure of PA) was used to collect the data at baseline and six-month follow-up assessments. Then the data were compared within and between groups using t-test and paired test using SPSS ۱۹ software. Findings: All ۱۱۰ ‘Health Volunteers’ (۵۵ in each group) were entered into the study. The mean±SD age of participants was ۳۵.۶۵±۱۰.۲۵ years. The results obtained from the analysis showed that the educational program improved attitude towards PA, perceived behavioral control, intention, behavior, and PCI among the intervention group (p<۰.۰۰۱). However, no significant changes occurred in the control group regarding the study variables (p>۰.۰۵). Conclusion: The TPB-directed educational program improved physical activity and physiological cost index. The study framework might be used as a practical template for interventions aimed at improving physical activity among female health volunteers.

Theory of Planned Behavior, Physical Activity, Physiological Cost Index, Women