Abstract:

 Introduction: Obesity and physically inactive lifestyles are associated with an increased risk for developing insulin resistance. It has been confirmed that insulin resistance is a common feature in many inflammatory diseases and can be recognized with overproduced levels of markers such as IL-6, IL-18 & CRP. The aim of this study was to determine whether obesity or inactivity are stronger factors in the develop mental insulin resistance, considering insulin resistance markers such as IL-6, IL-18 and CRP. Materials and Methods: Thirty-two healthy, male students participated in the present study, age 24. 8±2. 52 years, height 175. 47±6. 7, and weight 81. 64±20. 14). Weight and body fat were measured with the body composition set and levels of exercise was determined with the PA-Rscore questionnaire. All subjects based on body fat and levels of exercise were divided into 4 groups: Active obese(n=8), active, non-obese (n=8), inactive, obese (n=8) and inactive, non-obese (n=8). To determine fasting values of IL-6, IL-18, CRP, glucose and insulin blood samples were obtained at 8 a. m. Results: Obese subjects had higher resting levels of IL-6, IL18, CRP and insulin than lean subjects, with no significant difference between active lean and inactive lean subjects at resting levels of inflammatory markers. However there was a significant difference in the resting levels of IL-18 between active and inactive obese subjects (t=-2. 51 P=0. 031), and also a significant difference in resting levels of IL-6, IL-18,CRP, insulin and HOMA between inactive obese with active and inactive lean subjects, IL-18 having the strongest relationship with HOMA (r=0. 54 p=0. 001). Conclusion: Results indicated that obesity is a stronger factor than inactivity for development of insulin resistance. On the other hand, activity has anti-inflammatory effects, and hence can decrease the effects of obesity, in the development of insulin resistance.