Introduction and Objective: Obesity is known as a key factor in the development of systemic inflammation and can lead to changes in the population of macrophages in white adipose tissue. This study investigated the effect of strength training on the infiltration and polarization of macrophages in white adipose tissue of obese rats and compared the effects of two training periods of 14 and 30 days.

Methodology: This study is a quasi-experimental study with a pre-test and post-test design and included a control group. In this study, 40 obese rats were randomly divided into four groups: control group, obese group, 14-day strength training group and 30-day strength training group. The macrophage population, including total macrophages (F4/80+), type 1 and 2 macrophages, was examined using flow cytometry. Peripheral insulin sensitivity was also assessed by measuring phosphorylation. Data analysis was performed using descriptive and inferential statistical methods.

Results: The results showed that both training protocols improved peripheral insulin sensitivity through increased phosphorylation. The 14-day training regimen reduced total macrophage infiltration and macrophage type 2 levels without changing type 1 levels. In the 30-day resistance training group, significant differences were observed in total macrophage levels, type 1 macrophages, and ratio 2 compared to the obese group. Also, a decrease in the ratio 1/2 in epididymal tissue was recorded in the 14-day resistance training group.

Conclusion: This study shows that resistance training can have a positive effect on changes in macrophage polarization in white adipose tissue of obese rats. In particular,