Intermittent Fasting with Moderate-Intensity Physical Exercise Increased Melatonin but Did Not Reduce Body Mass Index in Obese Rats

Background: Intermittent Fasting (IF) is a dietarymethod studied to positively affect circadian rhythm and metabolism by increasing melatonin hormone that may promote weight loss in obese individuals. Objective: This study aimed to measure IF with moderate-intensity exercise on increasing melatonin levels and reduce Body Mass Index (BMI). Methodology: An experimental study with pre and post-test control group design was conducted on 36 obese male Wistar rats aged 4-5 months. The subjects weredivided randomly into two groups, the study and control groups, with 18 subjects in each group. The study group underwent IF for 12 hours with moderate-intensity physical exercise, while the control group was given a standard diet with moderate-intensity physical exercise. After four weeks of intervention, melatonin levels assessedusing ELISA (enzyme-linked immunosorbent assay); meanwhile, BMI was measured before and after treatment. The comparative test was conducted to compare the results between groups. Results: The results showed that the mean pretest and post-test melatonin levels in the study group increased significantly (0.353?0.01vs.0.479?0.01; p<0.001). Melatonin levels in the study group at the end of the study also showed a significant increase compared to the control group (0.194?0.03 vs. 0.479?0.01; p<0.001). However, the mean pretest and post-test BMI in the study group did not show any significant differences (0.353?0.01 vs. 0.351?0.0; p=0.965). The BMI comparison between the study and control groups also did not show any significant differences (0.351?0.01 vs. 0.354?0.01; p=0.432). Conclusion: IF with moderate-intensity exercise increased melatonin levels but did not reduce BMI in obese male Wistar rats. The duration and diet regimes of IF need to be further evaluated.