---

Background & objectives: ABCA1 plays an important role in HDL biosynthesis and cellular cholesterol homeostasis and is effective in preventing the formation of atherosclerotic plaques. This study aimed to investigate the effect of combined and rehabilitation training on ABCA1 gene expression in blood lymphocytes and lipid profile in middle-aged men with coronary bypass graft.
Methods: In this quasi-experimental study, 45 middle-aged men (mean age: 55.58±4.7 years) were selected by convenience sampling method and randomly divided into three groups of combined training (15 people), rehabilitation (n=15), and control (n=15). The combined training group included resistance and aerobic exercises and rehabilitation training group included aerobic exercises for 8 weeks (3 sessions per week). Blood samples were taken from all subjects at weeks 0 and 8 to measure the expression levels of ABCA1, HDL, and LDL genes. Kruskal-Wallis, one-way ANOVA, and Tukey post hoc tests were used for statistical analysis using SPSS software, and significance level was p≤0.05 .
Results: The results showed that eight weeks of combined training and rehabilitation training increased the expression level of the ABCA1 (p=0.001 and p=0.001, respectively) gene and plasma HDL (p=0.001 and p=0.012, respectively) level and decreased plasma LDL (p=0.001 and p=0.01, respectively) level. There was also a significant difference between the three groups in ABCA1 and HDL values in favor of the combined training group. 
Conclusion: It seems that combined training can be more effective than rehabilitation training to further increase ABCA1 gene expression and plasma HDL levels and decrease LDL level in middle-aged men with coronary bypass graft.