title: Gonadal hormones and semen quality in male runners. A volume threshold effect of endurance training.
abstract: Eleven high mileage runners (HR) (108.0 +/- 4.5 km.wk-1), 9 moderate mileage runners (MR) (54.2 +/- 3.7 km.wk-1) and 10 sedentary controls (SC) of similar age (28.3 +/- 1.5 yr) were studied to evaluate the effects of volume of endurance training on reproductive function in male runners. Levels of reproductive, adrenal and thyroid hormones were measured during a 1-hr period of serial blood sampling (q20 min) and urinary excretion of 24-hr luteinizing hormone (uLH) was determined on two separate days. Semen exams and sperm penetration of standard cervical mucus (Penetrak) were performed 2-5 times. Levels of total testosterone (TT) and free testosterone (FT) were significantly lower in HR (15.3 +/- 1.3 nmol.l-1 and 60.2 +/- 5.1 pmol.l-1) compared to MR (21.4 +/- 1.6 nmol.l-1 and 86.0 +/- 6.1 pmol.l-1) and SC (19.5 +/- 0.9 nmol.l-1 and 75.9 +/- 3.6 pmol.l-1). No differences (p > 0.05) were found in uLH, serum LH, follicle-stimulating hormone (FSH), and prolactin (PRL) among the three groups. No other hormonal differences (p > 0.05) were observed among the groups. Total motile sperm count and density were lower (p < 0.05) in HR than SC. Decreased (p < 0.0006) sperm motility and an increased (p < 0.004) population of immature sperm and round cells were observed in HR compared to MR and SC. Sperm penetration of bovine cervical mucus was also decreased (p < 0.024) in HR compared to SC. Volume of training, defined by km.wk-1 run, was significantly correlated to sperm motility, density and number of round cells.(ABSTRACT TRUNCATED AT 250 WORDS)
authors.affiliation: Department of Obstetrics and Gynecology, University of Connecticut Health Center, Farmington 06030.
authors.forename: M J
authors.initials: MJ
authors.lastname: De Souza
authors.forename: J C
authors.initials: JC
authors.lastname: Arce
authors.forename: L S
authors.initials: LS
authors.lastname: Pescatello
authors.forename: H S
authors.initials: HS
authors.lastname: Scherzer
authors.forename: A A
authors.initials: AA
authors.lastname: Luciano
mesh_terms: D000293:Adolescent; D000305:Adrenal Cortex Hormones / Q000097:blood; D000328:Adult; D000818:Animals; D001823:Body Composition; D002417:Cattle; D002582:Cervix Mucus / Q000502:physiology; D015331:Cohort Studies; D002149:Energy Intake; D005080:Exercise Test; D005640:Follicle Stimulating Hormone / Q000097:blood; D012739:Gonadal Steroid Hormones / Q000097:blood*; D006801:Humans; D007986:Luteinizing Hormone / Q000097:blood / Q000652:urine; D008297:Male; D010807:Physical Endurance / Q000502:physiology*; D011388:Prolactin / Q000097:blood; D012420:Running / Q000502:physiology*; D012661:Semen / Q000502:physiology*; D013076:Sperm Count; D013081:Sperm Motility / Q000502:physiology; D013094:Spermatozoa / Q000502:physiology; D013312:Stress, Physiological / Q000097:blood; D013963:Thyroid Hormones / Q000097:blood
chemical_list: D000305:Adrenal Cortex Hormones; D012739:Gonadal Steroid Hormones; D013963:Thyroid Hormones; D011388:Prolactin; D007986:Luteinizing Hormone; D005640:Follicle Stimulating Hormone