بررسی عوامل تأثیر گذار بر فعالیت فیزیکی دانشجویان پزشکی بر اساس الگوی بین نظریه‌ای

 Background and Objective: Nowadays, the importance of physical activity as a health promoting behavior has been well documented. The purpose of this study was prediction of transtheorical model (TTM)’s constructs on regular physical activity among medical students.   Materials and Methods: This study was a descriptive-analytic research that carried out on 307 medical students at Shahed University using census method in 2011. The instruments of data collection were demographic and standard scale of seven-day physical activity recall (PAR), and benefits scale & barriers scale. The TTM guided instrument development. Collected data was analyzed using SPSS version 16.   Results: The findings of descriptive statistics showed that mean age of students was 22.28 years (SD = 2.6) and 69.4% of participants were women. Mean of weekly physical activity in all of the students was 175.17 minutes, SD: 172.04, but in men a little more than women. The finding of analytic statistics showed that regression analysis predict that if 1 score increase to total scores of benefits caused 7 scores in addition to total scores of physical activity and 1 score increase to total scores of barriers caused 12 scores decrease to total scores of physical activity.   Conclusion: Those findings and using TTM constructs will help practitioners for intervention and to improve the physical activity among university students.