Abstract: There has been increasing awareness on the health benefits of physical activities or exercise and this led to community-based initiatives aimed at improving health and general well being. The duration of exercise, genetic factors, the physiologic characteristics and lifestyle of individuals are closely related to acute and chronic differences in hematologic parameters. Aim: The intent of this study was to investigate some haematological changes (PCV, TWBC and platelet counts) in male athletes pre- and post-exercise. Methods: A cross-sectional, longitudinal study was carried out on a total of 50 athletes who engaged in community-based regular fitness exercise for more than six months. The candidates were sampled before and immediately after strenuous exercise and PCV, TWBC and platelet counts assessed using standard methods. The TWBC and platelets count differed significantly (p>0.05) between pre- and post-exercise. No significant difference was observed in the PCV among the groups. Conclusion: In summary, our findings show that exercise improved significantly the cellular level of total white blood cells and platelet count. This consequently is of great importance to the immune defense and haemostatic function. There is need for future large scale evidence-based research aimed at advocacy, awareness creation and prioritizations in primary/preventive health policy formulation.