RESUMO
<b>Background and Objective:</b> Cardiomyocyte adaptation to exercise might require ROS as a central regulator. There is a limited study regarding the importance of ROS for inducing exercise-induced adaptation and its correlations with changes in histological scoring of cardiac muscles. The study aimed to explore the importance of physiological ROS induced by exercise and its correlation with Cardiomyocyte' histological appearance that is altered by <i>Moringa oleifera</i> leaves extract in Wistar rats. <b>Materials and Methods:</b> This was an animal experimental study, which use 4 groups of 24 Wistar rats divided into Control (Co), <i>Moringa</i> leaves extract (Mo), Exercise (Ex) and a combination of <i>Moringa </i>leaves extract and Exercise (MoEx). The <i>Moringa</i> leaves extract were given orally, 5 days a week, for 4 consecutive weeks. The exercise was given in moderate intensity, 5 days a week, also for 4 consecutive weeks. <b>Results:</b> This study found significant differences in heart weight and heart weight/body weight ratio in Ex group compared to the control. As for histology scoring, found that MoEx group has 16.7% cardiac hypertrophy and myofiber disarray compared to 83.3% mild hypertrophy and 50% mild disarray in Ex group. <b>Conclusion:</b> In summary, the study showed that the potential central role of exercise-induced physiological ROS for cardiac hypertrophy adaptation is altered by <i>Moringa oleifera </i>leaves extract treatment.