The Impact of Physical Exercise on Male Fertility Through Its Association with Various Processes and Aspects of Human Biology

Background/Objective: Infertility affects approx. 10-15% couples in industrialized countries. It has numerous causes, including genetic and environmental factors, lifestyle choices, and physiological disorders. Its increasing prevalence underlines the importance of research on interventions to improve reproductive health, with a strong focus on physical activity. Infertility research was traditionally mainly directed toward female health. Although the male factor is being increasingly accepted as being equally important, this area remains under-researched. The current review aims to focus mainly on the effects of physical activity on male fertility, through its effects connected with the immune function, cardiovascular system, hormones, metabolism, and physical interaction with the male reproductive system. Materials and Methods: A comprehensive literature review of studies addressing the effects of physical activity on male fertility was conducted via PubMed/Medline, Scopus, and Web of Science. Mostly recent studies were included, with a small number of older ones used in cases when their content remains relevant. The review focused on articles studying the processes involved and associations between physical activity and male fertility through immune and cardiovascular effects, endocrine modulation, the influence on obesity and insulin metabolism, and the physical impact on the body. Results: The findings revealed the existence of a fairly strong consensus that moderate physical activity enhances semen quality, hormonal balance, and metabolic health, positively influencing male fertility. Physical activity reduces inflammation and oxidative stress, enhances cardiovascular functioning, and contributes to oxygen and nutrient supply to the reproductive organs. On the contrary, strenuous training can adversely affect fertility, mostly through hormonal disruption and oxidative stress, but can also have all sorts of indirect effects on fertility by sports-related behavior and incidents, such as tight clothing or overheating. Conclusion: Physical activity can affect male fertility in numerous ways, positively influencing reproductive health when performed at moderate intensity. Understanding the balance between beneficial and excessive exercise as well as the impact of incidental factors related to performing sports regularly are extremely important in optimizing lifestyle-oriented interventions aimed at male fertility improvement.