Previous studies that examined the effects of endurance-type and anaerobic-type exercise on GH suggested that the exercise input should be sufficient to cause a sizeable metabolic effect (e.g., above the lactic anaerobic threshold) to stimulate GH secretion (8). Interestingly, we found that even a moderate volleyball training (mean end-exercise lactate level 5.4 mmol·L−1) led to a significant increase in GH levels. Moreover, previous studies indicated that the exercise-induced GH peak occurs 25 to 35 minutes after the start of exercise irrespective of the exercise duration and occurs a few minutes earlier in women (6,27,30,33). Therefore, because blood samples were collected in the present study only before and at the end of exercise (1 hour), and not 25 to 30 minutes after the beginning of exercise, it is possible that the exercise-related GH peak might have been even higher if these blood samples were drawn earlier.
Baseline and postexercise testosterone levels were significantly higher in men compared with women. However, training was associated with an increase in testosterone levels in both genders, and the response to training was not significantly different between genders. The testosterone increase may indicate an exercise-associated anabolic adaptation. Although the effects of different types of exercise on testosterone levels in men are very well studied, few previous studies examined the effect of resistance and endurance exercise on testosterone level in women (e.g., (3,31)). Circulating levels of testosterone have been shown to increase in response to acute bout of endurance exercise in women across a wide age range (from young adult to premenopausal (2-4)). In contrast, the effect of resistance training on circulating testosterone levels was less consistent. Several studies demonstrated an increase of 16 to 25% in testosterone levels after resistance exercise in women (5,23,32). Other studies have failed to demonstrate an increase in testosterone levels in women at different stages of the menstrual cycle (15,17). Very few studies examined the effect of team sports training on testosterone levels in female athletes. In contrast to our findings, there were no significant changes in circulating testosterone and salivary testosterone levels in elite female players after an intense water polo practice and handball match, respectively (9,12).
In contrast to male athletes, the source of the exercise-induced testosterone production in female athletes is the adrenal gland and obviously not the testicles. Accordingly, postexercise increases in testosterone levels in female athletes were usually accompanied by a parallel increase in cortisol, dehydroepiandrostenedione, and/or androstenedione levels (3,5,12). Interestingly, in the present study, the volleyball practice did not lead to a significant increase in cortisol levels. However, there was a significant correlation between the exercise-induced changes in testosterone and cortisol (r = 0.53, p < 0.01) in the adolescent female volleyball players. Finally, despite the significantly lower testosterone levels in the female players (baseline and post exercise), there was no significant difference in the response to exercise between genders. The results suggest, therefore, that increase in testosterone levels may play an important role in the anabolic response to exercise in female athletes as well. In addition, the parallel exercise-related increase in GH and testosterone suggests a possible mechanistic link for the exercise-associated stimulation, secretion, or release of these hormones.
The present study examined the hormonal and inflammatory responses to a single typical volleyball practice. Changes in the GH and testosterone suggested mainly exercise-related anabolic adaptations, and increases of IL-6 may indicate its important role in muscle tissue repair after volleyball training. There were no significant gender-related differences in the hormonal and inflammatory responses to the volleyball practice, suggesting that even testosterone, despite the low basal and postexercise levels in female athletes, can be used as an exercise-associated anabolic marker. The results indicate that changes in the anabolic-catabolic hormonal balance and in circulating inflammatory cytokines can be used by the athlete and/or his coach to gauge the training intensity also in team sports such as volleyball. It is clear that these responses cannot be used as a marker for every practice, unless future techniques provide immediate results (like the current ability to assess lactate levels). However, the response of these hormones can be used occasionally in different types of team sports, important training sessions, or training camps or before main competitions or tournaments as an objective quantitative tool to monitor training load and to better plan training cycles throughout the competitive season.
This work was supported by grants MO1-RR00827 and HD 23969 from the National Institutes of Health.
1. Adams, GR. Autocrine/paracrine IGF-I
and skeletal muscle adaptation. J Appl Physiol
93: 1159-1167, 2002.
2. Consitt, LA, Copeland, JL, and Tremblay, MS. Hormone responses to resistance versus endurance exercise in pre-menopausal females. Can J Appl Physiol
26: 574-587, 2001.
3. Consitt, LA, Copeland, JL, and Tremblay, MS. Endogenic anabolic hormone responses to endurance versus resistance exercise and training
in women. Sports Med
32: 1-22, 2002.
4. Copeland, JL, Consitt, LA, and Tremblay, MS. Hormonal responses to endurance and resistance exercise in female aged 19-69 years. J Gerontol A Biol Sci Med Sci
57: 58-65, 2002.
5. Cumming, DC, Wall, SR, Galbraith, MA, and Delcastro, AN. Reproductive hormone responses to resistance exercise. Med Sci Sports Exerc
19: 234-238, 1987.
6. Eliakim, A, Brasel, JA, and Cooper, DM. GH
response to exercise: Assessment of the pituitary refractory period, and relationship with circulating components of the GH
axis in adolescent females. J Pediatr Endocrinol Metab
12: 47-55, 1999.
7. Eliakim, A, Nemet, D, and Cooper, DM. Exercise, training
and the GH
axis. In: The Endocrine System in Sports and Exercise
. Kraemer, WJ, and Rogol, AD, eds. Oxford, UK: Blackwell publishing, 2005. pp. 165-179.
8. Felsing, NE, Brasel, JA, and Cooper, DM. Effect of low- and high-intensity exercise on circulating growth hormone in men. J Clin Endocrinol Metab
75: 157-162, 1992.
9. Filaire, E and Lac, G. Dehydroepiandrostenedione rather than testosterone shows saliva androgen responses to exercise in female handball players. Int J Sports Med
21: 17-20, 2000.
10. Green, JM, Mclester, JR, Crews, TR, Wickwire, PJ, Pritchett, RC, and Lomax, RG. RPE association with lactate and heart rate during high-intensity interval cycling. Med Sci Sports Exerc
38: 167-172, 2006.
11. Haddad, F, Zaldivar, F, Cooper, DM, and Adams, GR. IL-6 induced skeletal muscle atrophy. J Appl Physiol
98: 911-917, 2005.
12. Hale, RW, Kosasa, T, Krieger, J, and Pepper, S. A marathon: The immediate effect on female runners' luteinizing hormone, follicle-stimulating hormone, prolactin, testosterone and cortisol levels. Am J Obstet Gynecol
146: 550-556, 1983.
13. Ho, KY, Evans, WS, Blizzard, RM, Veldhuis, JD, Merriam, GR, Samojlik, E, Furlanetto, R, Rogol, AD, Kaiser, DL, and Thomer, MO. Effects of sex and age on the 24-hour profile of growth hormone secretion in man: Importance of endogenous estradiol concentrations. J Clin Endocrinol Metab
64: 51-58, 1987.
14. Jaffe, CA, Ocampo-Lim, B, Gue, W, Krueger, K, Sugahara, I, Demott-Friberg, R, Bermann, M, and Barkan, AL. Regulatory mechanisms of growth hormone secretion are sexually dismorphic. J Clin Invest
102: 153-164, 1998.
15. Kraemer, WJ, Fleck, SJ, Dziados, JE, Harman, EA, Marchitelli, AJ, Gordon, SE, Mello, R, Frykman, PN, Koziris, LP, and Triplett, NT. Changes in hormone concentration after different heavy resistance exercise protocols in women. J Appl Physiol
75: 594-604, 1993.
16. Kraemer, WJ, Harman, FS, Vos, NH, Gordon, SE, Nindl, BC, Marx, JO, Gomez, AL, Volek, JS, Ratamess, NA, Mazzetti, SA, Bush, JA, Dohi, K, Newton, RU, and Häkkinen, K. Effects of exercise and alkalosis on serum insulin-like growth factor I and IGF-binding protein-3. Can J Appl Physiol
25: 127-138, 2000.
17. Kraemer, WJ, Patton, JF, Gordon, SE, Harman, EA, Deschenes, MR, Reynolds, K, Newton, RU, Triplett, NT, and Dziados, JE. Compatibility of high-intensity strength and endurance training
on hormonal and skeletal muscle adaptations. J Appl Physiol
78: 976-989, 1995.
18. Lohman, TG, Pollock, ML, Slaughter, MH, Brandon, LJ, and Boileau, RA. Methodological factors and the prediction of body fat in female athletes. Med Sci Sports Exerc
16: 92-96, 1984.
19. Meckel, Y, Eliakim, A, Seraev, M, Zaldivar, F, Cooper, DM, Sagiv, M, and Nemet, D. The effect of a brief sprint interval exercise on growth factors and inflammatory mediators. J Strength Cond Res
23: 225-230, 2009.
20. Nemet, D, Oh, Y, Kim, HS, Hill, MA, and Cooper, DM. The effect of intense exercise on inflammatory cytokines
and growth mediators in adolescent boys. Pediatrics
110: 681-689, 2002.
21. Nemet, D, Rose-Gottron, CM, Mills, PJ, and Cooper, DM. Effect of water polo practice on cytokines
, growth mediators and leukocytes in girls. Med Sci Sports Exerc
35: 356-363, 2003.
22. Nieman, DC, Henson, DA, Smith, LL, Utter, AC, Vinci, DM, Davis, JM, Kaminsky, DE, and Shute, M. Cytokine changes after a marathon race. J Appl Physiol
91: 109-114, 2001.
23. Nindl, BC, Kraemer, WJ, Gotschalk, LA, Marx, JO, Volek, JS, Bush, FA, Häkkinen, K, Newton, RU, and Fleck, SJ. Testosterone response after resistance exercise in women: Influence of regional fat distribution. Int J Sports Med
11: 451-465, 2001.
24. Ostrowski, K, Rohde, T, Asp, S, Schjerling, P, and Pedersen, BK. Pro- and anti-inflammatory cytokine balance in strenuous exercise in humans. J Physiol
515: 287-291, 1999.
25. Pedersen, BK, Steensberg, A, Fischer, C, Keller, C, Keller, P, Plomgaard, P, Wolsk-Petersen, E, and Febbraio, MA. The metabolic role of IL-6 produced during exercise: Is IL-6 an exercise factor? Proc Nutr Soc
63: 263-267, 2004.
26. Pincus, SM, Gevers, EF, Robinson, IC, Van Den Berg, G, Roelfsema, F, Hartman, ML, and Veldhuis, JD. Females secrete growth hormone with more process irregularity than males in both humans and rats. Am J Physiol
270: E107-E115, 1996.
27. Schwarz, AJ, Brasel, JA, Hintz, RL, Mohan, S, and Cooper, DM. Acute effect of brief low- and high-intensity exercise on circulating IGF-I
, II, and IGF binding protein-3 and its proteolysis in young healthy men. J Clin Endocrinol Metab
81: 3492-3497, 1996.
28. Steensberg, A, Keller, C, Starkie, RL, Osada, T, Febbraio, MA, and Pedersen, BK. IL-6 and TNF-alpha expression in, and release from, contracting human skeletal muscle. Am J Physiol Endocrinol Metab
283: E1272-E1278, 2002.
29. Stokes, K. Growth hormone responses to sub-maximal and sprint exercise. Growth Horm IGF Res
13: 225-238, 2003.
30. Stokes, K, Nevill, M, Frystyk, J, Lakomy, H, and Hall, G. Human growth hormone response to repeated bouts of sprint exercise with different recovery periods between bouts. J Appl Physiol
99: 254-1261, 2005.
31. Viru, A and Viru, M. Resistance exercise and testosterone. In: The Endocrine System in Sports and Exercise
. W.J. Kraemer and A.D. Rogol, eds. Oxford, UK: Blackwell Publishing, 2005. pp. 319-338.
32. Weiss, LW, Kureton, KJ, and Thomson, FN. Comparison of serum testosterone and androstenedione responses to weight lifting in men and women. Eur J Appl Physiol
50: 413-419, 1983.
33. Wideman, L, Weltman, JY, Shah, N, Story, S, Veldhuis, JD, and Weltman, A. Effects of gender
on exercise-induced growth hormone release. J Appl Physiol
87: 1154-1162, 1999.