Physical exercise at high altitude is associated with a testicular dysfunction leading to reduced sperm concentration but healthy sperm quality

ObjectiveTo explore the effect of physical exercise at high altitudes (HA) on male reproductive system.DesignProspective study.SettingAndrology Clinic, University of L'Aquila, Italy.Patient(s)Seven male mountaineers involved in an expedition at 5,900 m.Intervention(s)Semen analysis, sperm DNA fragmentation with flow cytometry, and reproductive hormone levels.Main Outcome Measure(s)Hormone levels were evaluated at sea level (SL) at baseline (SL-pre), after 22 days of exercise at HA (intermediate), and after 10 days upon reaching SL (SL-post). Sperm parameters, percentage of sperm with fragmented DNA, and body composition measures were evaluated at SL-pre and at SL-post.Result(s)A reduction of sperm concentration, of body mass index (BMI), of waist circumference, and of percentage of body fat was observed at SL-post compared with SL-pre values. Increased levels of FSH and PRL were observed at the intermediate point, and normalized at SL-post, whereas T was higher at SL-post compared with SL-pre levels.Conclusion(s)Physical exercise at HA is associated with a testicular dysfunction leading to a reduced sperm concentration probably through an altered spermiation. The improved body composition after physical exercise might explain the higher T levels observed after the expedition.