Introduction: The present research aimed to review the effect of a 15-day cinnamon supplementation on hematocrit and mean arterial blood pressure in response to one session aerobic exercise.

Materials & Methods: In this semi experimental study, 24 male voluntary staff of Fars Islamic Azad university, science research branch by getting testimonial and university ethics committee selected as subject purposively and base on their aerobic power divided in three groups (1 g cinnamon, 1.5 g cinnamon and control). Blood sampling gathered before and after training protocol (30min running by intensity of 55-65% maximum heart rate). For analysis of data used dependent test, one way ANOVA and LSD post hoc test (α=0.05).

Result: Results showed 15 days 1.5 g cinnamon supplementation increases the mean arterial blood pressure (from 91.61±6.78 to 100.70±6.24) (p=0.02) in response to one session aerobic exercise nevertheless 1 and 1.5 g cinnamon supplementation have no significant effect on fasting hematocrit (p= 0.15) and mean arterial blood pressure (p= 0.90) and hematocrit (p= 0.55) following one session aerobic exercise.

Conclusion: Consumption of 1 and 1.5 g cinnamon supplementation have no significant effect on the changes of hematocrit following one session aerobic exercise; nevertheless, 1.5 g cinnamon supplementation increases mean arterial blood pressure following one aerobic exercise.