Subclinical alterations in hormone and semen profile in athletes.
OBJECTIVE
To investigate the effects of two forms of exercise, endurance training (running) and resistance training (weight lifting), on reproductive function in male athletes.


METHODS
Cross-sectional study.


METHODS
Reproductive Endocrinology and Exercise Laboratory.


METHODS
Twenty-eight healthy male volunteers, 18 to 35 years of age, including 10 endurance-trained runners, 8 resistance-trained weight-lifters, and 10 sedentary controls.


METHODS
Hormonal evaluation included determination of plasma levels of total testosterone (T), serum levels of free T, luteinizing hormone (LH), follicle-stimulating hormone, prolactin, and estradiol, and urinary excretion of LH. Semen analyses included an evaluation of sperm characteristics in terms of density, count, motility, and morphology, and a determination of in vitro sperm penetration of standard bovine cervical mucus.


RESULTS
Compared with sedentary controls, endurance-trained and resistance-trained athletes presented with significantly lower levels of total and free T. There were no significant differences in the serum levels of all other circulating and urinary hormone measurements among the three groups. Sperm density, motility, and morphology were significantly altered only in the endurance-trained runners. In vitro sperm penetration of standard cervical mucus was significantly reduced in the endurance-trained runners.


CONCLUSIONS
Both endurance and resistance training modify the male reproductive hormone profile in a similar manner; however, only endurance training, in the form of running, is associated with subclinical modifications in semen characteristics.
Arce
J C
JC
Department of Obstetrics and Gynecology, University of Connecticut Health Center, Farmington 06030-1230.
De Souza
M J
MJ
Pescatello
L S
LS
Luciano
A A
AA
D000293:Adolescent; D000328:Adult; D005260:Female; D012739:Gonadal Steroid Hormones / Q000097:blood* / Q000652:urine*; D006801:Humans; D008297:Male; D010806:Physical Education and Training; D010807:Physical Endurance; D012661:Semen / Q000502:physiology*; D013076:Sperm Count; D013081:Sperm Motility; D013084:Sperm-Ovum Interactions; D013177:Sports
D012739:Gonadal Steroid Hormones