Does exercise training affect reproductive hormones in women?

Area of Science:

• Reproductive endocrinology
• Sports medicine
• Exercise physiology

Background:

• Increasing participation of women in strenuous athletic activities has led to a rise in reproductive disorders.
• Clinical issues such as infertility and decreased bone density are reported in female athletes.
• The potential impact of exercise on female reproductive health requires careful scientific evaluation.

Purpose of the Study:

• To critically review the evidence linking exercise training to reproductive disorders in female athletes.
• To assess the strength of the causal chain between exercise and hormonal changes affecting reproduction.
• To identify methodological limitations in existing research on this topic.

Main Methods:

• Review focused on studies comparing trained versus untrained women (cross-sectional or longitudinal).
• Evaluated the methodological rigor, including precautions, techniques, and protocols used in the studies.
• Assessed the consistency and potential biases of reported findings.

Main Results:

• Most published studies have significant methodological flaws, limiting their value.
• Fewer, more rigorous studies suggest suppression of gonadotropin and ovarian steroids in trained women.
• Even these findings may be confounded, and the causal link between exercise and reproductive suppression is not definitively proven.

Conclusions:

• The direct causal relationship between exercise training and reproductive disorders in female athletes is not yet proven.
• If exercise does cause hormonal suppression, it may depend on training intensity or the rate of intensity increase.
• Further high-quality research is needed to confirm the link and explore influencing factors like training parameters, gynecologic age, body composition, diet, and psychologic status.