Abstract:The beneficial effects of physical exercise on general health are well known; however, as exercise imposes great physical stress that challenges homeostasis, it can be detrimental to certain organs/systems of the body when it is exhaustively performed. Decreased seminal parameters and sex hormone levels have been reported in male athletes and, therefore, a possible impairment of male fertility has been linked to exercise in a volume, intensity, and modality dependent-manner. Also, inherent characteristics of sportsmen (e.g. training level, adaptive capacity) may modify the response. This article aims to review the relevant literature regarding exercise and male factor infertility, while at the same time explores the possible underlying mechanisms that might be involved in this observable fact.