The Response of Sexual and Stress Hormones of Male Pro-Cyclists During Continuous Intense Competition

Abstract

The aim of this study was to compare hormonal changes in plasma total testosterone (T), cortisol (C), luteinizing hormone (LH), follicle-stimulating hormone (FSH) and prolactin (P) in two world-class teams, both consisting of 9 top male pro-cyclists, during a real sports situation (the 1998 “Vuelta a España”, a 3-week multi-stage international cycling competition). Venous blood samples were taken the day before the race (S0), after 1 week (S1), after 2 weeks (S2) and at the end of the race (S3). The S0 T level was significantly lower in the team with more racing days in the previous month. There was a significant basal T decrease (p < 0.05) during the race in comparison with the initial value, in spite of the difference in S0 T level between teams. However, there was no difference between teams in the mean decrease in T level. C decreased significantly between S0 and S1 and between S1 and S2, but not between S2 and S3. There were no differences in P concentration between teams or throughout the study, except for a significant increase between S2 and S3. There were no initial differences in LH nor FSH concentration between the teams, nor at any of the study follow-up times. We conclude that in professional top-level athletes S0 T values depend on the number of competition days of the previous month. We observed a similar decrease in the T levels in both teams, independent of the absolute S0 values. In both teams C decreased during long-lasting cycling competition.

Key words

Cycling - endurance exercise - long-term exercise - testosterone - cortisol - prolactin - LH - FSH

References

• 1 Aakvaag A, Sand T, Opstad P K, Fonnum F. Hormonal changes in serum in young men during prolonged physical strain.  Eur J Appl Physiol. 1978;  39 283-291
• 2 Barron GL, Noakes TD, Levy W, Smith C, Millar R P. Hypothalamic dysfunction in overtrained athletes.  J Clin Endocrinol Metab. 1985;  60 803-806
• 3 Bonifaci M, Bela E, Carli G, Lodi L, Martelli G, Zhu B, Lupo C. Influence of training on the response of androgen plasma concentrations to exercise in swimmers.  Eur J Appl Physiol. 1995;  70 109-114
• 4 Cumming D C, Quigley M E, Yen S SC. Acute suppresion of circulating testosterone levels by cortisol in men.  J Clin Endocrinol Metab. 1983;  57 671-673
• 5 de Meirleir K L, Baeyens L, L'Hermite-Baleriaux M, L'Hermite M, Hollmann W. Exercise-induced prolactin release is related to anaerobiosis.  J Clin Endocrinol Metab. 1985;  60 1250-1252
• 6 Dessypris A, Kuoppasalmi K, Adlercreutz H. Plasma cortisol, testosterone, androstenedione and luteinizing hormone (LH) in a non-competitive marathon run.  J Steroid Biochem. 1976;  7 33-37
• 7 Dill D B, Costill D L. Calculation of percentage changes in volume of blood plasma and red cells in dehydration.  J Appl Physiol. 1974;  37 247-248
• 8 Dressendorfer R H, Wade C E. Effects of a 15-d race on plasma steroid levels and leg muscle fitness in runners.  Med Sci Sports Exerc. 1991;  23 954-958
• 9 Duclos M, Corcuff J B, Rashedi M, Fougere V, Manier G. Does functional alteration of the gonadotropic axis occur in endurance trained athletes during and after exercise - A preliminary study.  Eur J Appl Physiol. 1996;  73 427-433
• 10 Fahrner C L, Hackney A C. Effects of endurance exercise on free testosterone concentration and the binding affinity of sex hormone binding globulin (SHBG).  Int J Sports Med. 1998;  19 12-15
• 11 Fernández-García B, Terrados N, Pérez-Landaluce J, Rodríguez M. Intensity of exercise during road pro-cycling competition.  Med Sci Sports Exerc. 2000;  32 1002-1006
• 12 García-Rovés P M, Terrados N, Fernández S F, Patterson A M. Macronutrients intake of top level cyclists during continuous competition-change in the feeding pattern.  Int J Sports Med. 1998;  19 61-67
• 13 Gulledge T P, Hackney A C. Reproducibility of low resting testosterone concentrations in endurance trained men.  Eur J Appl Physiol. 1996;  73 582-583
• 14 Hackney A C, Sinning W E, Bruot B C. Reproductive hormonal profiles of endurance-trained and untrained males.  Med Sci Sports Exerc. 1988;  20 60-65
• 15 Hackney A C, Sinning W E, Bruot B C. Hypothalamic-pituitary-testicular axis function in endurance-trained males.  Int J Sports Med. 1990;  11 298-303
• 16 Hackney A C, Premo M C, Mcmurray R G. Influence of aerobic versus anaerobic exercise on the relationship between reproductive hormones in men.  J Sports Sci. 1995;  13 305-311
• 17 Häkkinen K, Pakarinen A, Alén M, Kauhanen H, Komi P V. Neuromuscular and hormonal adaptations in athletes to strength training in two years.  J Appl Physiol. 1988;  65 2406-2412
• 18 Hoogeveen A R, Zonderland M L. Relationship between testosterone, cortisol and performance in professional cyclists.  Int J Sports Med. 1996;  17 423-428
• 19 Inder W J, Hellemans J, Ellis M J, Evans M J, Livesey J H, Donald R A. Elevated basal adrenocorticotropin and evidence for increased central opioid tone in highly trained athletes.  J Clin Endocrinol Metab. 1995;  80 244-248
• 20 Inder W J, Livesey J H, Ellis M J, Evans M J, Donald R A. The effect of B-endorphin on basal and insulin-hypoglycaemia stimulated levels of hypothalamic-pituitary-adrenal axis hormones in normal human subjects.  Clin Endocrinol. 1996;  44 7-13
• 21 Kraemer W J, Fleck S J, Callister R, Shealy M, Dudley G A, Maresh C M, Marchitelli L, Cruthirds C, Murray T, Falkel J E. Training responses of plasma beta-endorphin, adrenocorticotropin and cortisol.  Med Sci Sports Exerc. 1989;  21 146-153
• 22 Kujala U K, Alen M, Huhtaniemi T. Gonadotrophin-releasing hormone and human chorionic gonadotrophin test reveal that both hypothalamic and testicular endocrine functions are suppressed during acute prolonged physical exercise.  Clin Endocrinol. 1990;  33 219-225
• 23 Lehmann M, Gastmann U, Petersen K G, Khalaf A N, Kinizia K, Fisher S, Kerp L, Keul J. Influence of 6-weeks, 6 days per week training on pituitary function in recreational athletes.  Br J Sports Med. 1993;  27 186-192
• 24 Lucia A, Chicharro J L, Pérez M, Serratosa L, Bandrés F, Legido J C. Reproductive function in male endurance athletes: sperm analysis and hormonal profile.  J Appl Physiol. 1996;  81 2627-2636
• 25 Lucia A, Hoyos J, Carvajal A, Chicharro J L. Heart rate response to professional road cycling: the tour the France.  Int J Sports Med. 1999;  20 167-172
• 26 Luger A, Deuster P A, Kyle S B, Gallucci W T, Montgomery L C, Gold P W, Loriaux D L, Chrousos G P. Acute hypothalamic-pituitary-adrenal responses to the stress of treadmill exercise. Physiologic adaptations to physical training.  N Engl J Med. 1987;  316 1309-1315
• 27 McColl E M, Wheeler G D, Gomes P, Bhambhani Y, Cumming C D. The effects of acute exercise on pulsatile LH release in high-mileage male runners.  Clin Endocrinol. 1989;  31 617-621
• 28 McConnie S E, Barkan A, Lampman R M, Schork M A, Beitins I Z. Decrease hypothalamic gonadotropin-releasing hormone secretion in male marathon runners.  N Engl J Med. 1986;  315 411-417
• 29 Opstad P K, Aakvaag A. Decreased serum levels of oestradiol, testosterone and prolactin during prolonged physical strain and sleep deprivation, and the influence of a high calorie diet.  Eur J Appl Physiol Occup Physiol. 1982;  49 343-348
• 30 Quigley M E, Sheehan K C, Caspers R F, Yen S SC. Evidence for increased opioid inhibition of LH secretion in hyperprolactinemic women with pituitary microadenomas.  J Clin Endocrinol Metab. 1980;  50 427-430
• 31 Seidman D S, Lolev E, Deuster P A, Burstein R, Arnon R, Epstein Y. Androgenic response to long term physical training in male subjects.  Int J Sports Med. 1990;  11 421-424
• 32 Smallridge R C, Whorton N E, Burman K D, Ferguson E W. Effects of exercise and physical fitness on the pituitary-thyroid axis and on prolactin secretion in male runners.  Metabolism. 1985;  34 949-954
• 33 Snyder A C, Kuipers H, Cheng B, Servais R, Fransen E. Overtraining following intensified training with normal muscle glycogen.  Med Sci Sports Exerc. 1995;  27 1063-1070
• 34 Strauss R H, Lanese R R, Malarkey W. Weight loss in amateur wrestlers and its effect on serum testosterone levels.  JAMA. 1985;  254 3337-3338
• 35 Wheeler G D, Wall S R, Belcastro A N, Cumming D C. Reduced serum testosterone and prolactin levels in male distance runners.  JAMA. 1984;  252 514-516
• 36 Wheeler G D, Sing M, Pierce W D, Epling F, Cumming D C. Endurance training decreases serum testosterone levels in men without change in luteinizing hormone pulsatile release.  J Clin Endocrinol Metab. 1991;  72 422-425
• 37 Wittert G A, Livesey J H, Espiner E A, Donald R A. Adaptation of the hypothalamopituitary adrenal axis to chronic exercise stress in humans.  Med Sci Sports Exerc. 1996;  28 1015-1019