Journal of Clinical Endocrinology & Metabolism, Vol 81, 3986-3992, Copyright © 1996 by Endocrine Society

ARTICLES

Physical fitness, endurance training, and the growth hormone-insulin- like growth factor I system in adolescent females

A Eliakim, JA Brasel, S Mohan, TJ Barstow, N Berman and DM Cooper
Department of Pediatrics, Harbor- University of California-Los Angeles Medical Center, Torrance 90509, USA.

We examined the relationship between physical fitness and circulating components of the GH-insulin-like growth factor I (IGF-I) system [i.e. GH, GH-binding protein (GHBP), IGF-I, and IGF-binding proteins 1-5 (IGFBP-1 through-5)] in adolescent females (age range, 15-17 yr). The study consisted of 1) a cross-sectional protocol (n = 23) in which GH- IGF-I components were correlated with fitness, as estimated by thigh muscle volume and maximal O2 uptake; and 2) a prospective study in which fitness, GH-IGF-I system components, and osteocalcin were examined before and after a 5-week period of endurance-type training (control, n = 6; trained, n = 10). The cross-sectional analysis revealed significant (P < 0.05) positive correlations between fitness and 1) mean 12-h overnight GH levels, 2) GHBP, and 3) IGF-I. Muscle volume was negatively correlated with both IGFBP-2 and -4. The prospective training study was associated with 1) increases in circulating osteocalcin (39 +/- 14%; P < 0.007), and 2) decreases in IGF-I (-14 +/- 5%; P < 0.05) and IGFBP-5 (-10 +/- 4%; P < 0.04). Unexpectedly, IGFBP-3 fell in both control (-8 +/- 2%; P < 0.01) and trained subjects (-5 +/- 3%; P < 0.05), and GHBP was reduced only among control subjects (-10 +/- 7%; P < 0.04). In summary, fitter adolescent girls tended to have increased mean serum GH, GHBP, and IGF-I. In contrast, brief endurance training led to increases in muscle mass and serum osteocalcin that were not accompanied by increases in GH or IGF- I. In fact, training may, in the short term, have led to a catabolic state hormonally expressed by reductions in IGF-I and IGFBP-5.

This article has been cited by other articles:

				K. R. Rarick, M. A. Pikosky, A. Grediagin, T. J. Smith, E. L. Glickman, J. A. Alemany, J. S. Staab, A. J. Young, and B. C. Nindl Energy flux, more so than energy balance, protein intake, or fitness level, influences insulin-like growth factor-I system responses during 7 days of increased physical activity J Appl Physiol, November 1, 2007; 103(5): 1613 - 1621. [Abstract] [Full Text] [PDF]

				J. Gibney, M.-L. Healy, and P. H. Sonksen The Growth Hormone/Insulin-Like Growth Factor-I Axis in Exercise and Sport Endocr. Rev., October 1, 2007; 28(6): 603 - 624. [Abstract] [Full Text] [PDF]

				J. Z. Kasa-Vubu, W. Ye, K. T. Borer, A. Rosenthal, and T. Meckmongkol Twenty-Four Hour Growth Hormone and Leptin Secretion in Active Postpubertal Adolescent Girls: Impact of Fitness, Fatness, and Age at Menarche J. Clin. Endocrinol. Metab., October 1, 2006; 91(10): 3935 - 3940. [Abstract] [Full Text] [PDF]

				T. L. Ballard, J. A Clapper, B. L Specker, T. L Binkley, and M. D Vukovich Effect of protein supplementation during a 6-mo strength and conditioning program on insulin-like growth factor I and markers of bone turnover in young adults Am. J. Clinical Nutrition, June 1, 2005; 81(6): 1442 - 1448. [Abstract] [Full Text] [PDF]

				A. Berggren, C. Ehrnborg, T. Rosen, L. Ellegard, B.-A. Bengtsson, and K. Caidahl Short-Term Administration of Supraphysiological Recombinant Human Growth Hormone (GH) Does Not Increase Maximum Endurance Exercise Capacity in Healthy, Active Young Men and Women with Normal GH-Insulin-Like Growth Factor I Axes J. Clin. Endocrinol. Metab., June 1, 2005; 90(6): 3268 - 3273. [Abstract] [Full Text] [PDF]

				J. D. Veldhuis, J. N. Roemmich, E. J. Richmond, A. D. Rogol, J. C. Lovejoy, M. Sheffield-Moore, N. Mauras, and C. Y. Bowers Endocrine Control of Body Composition in Infancy, Childhood, and Puberty Endocr. Rev., February 1, 2005; 26(1): 114 - 146. [Abstract] [Full Text] [PDF]

				L. Rosendal, H. Langberg, A. Flyvbjerg, J. Frystyk, H. Orskov, and M. Kjar Physical capacity influences the response of insulin-like growth factor and its binding proteins to training J Appl Physiol, November 1, 2002; 93(5): 1669 - 1675. [Abstract] [Full Text] [PDF]

				J. Manetta, J. F. Brun, L. Maimoun, A. Callis, C. Prefaut, and J. Mercier Effect of training on the GH/IGF-I axis during exercise in middle-aged men: relationship to glucose homeostasis Am J Physiol Endocrinol Metab, November 1, 2002; 283(5): E929 - E936. [Abstract] [Full Text] [PDF]

				D. Nemet, Y. Oh, H.-S. Kim, M. Hill, and D. M. Cooper Effect of Intense Exercise on Inflammatory Cytokines and Growth Mediators in Adolescent Boys Pediatrics, October 1, 2002; 110(4): 681 - 689. [Abstract] [Full Text] [PDF]

				N. A. Georgopoulos, K. B. Markou, A. Theodoropoulou, G. A. Vagenakis, D. Benardot, M. Leglise, J. C. A. Dimopoulos, and A. G. Vagenakis Height Velocity and Skeletal Maturation in Elite Female Rhythmic Gymnasts J. Clin. Endocrinol. Metab., November 1, 2001; 86(11): 5159 - 5164. [Abstract] [Full Text] [PDF]

				P. TIRAKITSOONTORN, E. NUSSBAUM, C. MOSER, M. HILL, and D. M. COOPER Fitness, Acute Exercise, and Anabolic and Catabolic Mediators in Cystic Fibrosis Am. J. Respir. Crit. Care Med., October 15, 2001; 164(8): 1432 - 1437. [Abstract] [Full Text] [PDF]

				J L Chicharro, A Lopez-Calderon, J Hoyos, A I Martin-Velasco, G Villa, M A Villanua, and A Lucia Effects of an endurance cycling competition on resting serum insulin-like growth factor I (IGF-I) and its binding proteins IGFBP-1 and IGFBP-3 Br. J. Sports Med., October 1, 2001; 35(5): 303 - 307. [Abstract] [Full Text] [PDF]

				D. R. Bolster, M. A. Pikosky, L. M. McCarthy, and N. R. Rodriguez Exercise Affects Protein Utilization in Healthy Children J. Nutr., October 1, 2001; 131(10): 2659 - 2663. [Abstract] [Full Text] [PDF]

				A. Eliakim, T. P. Scheett, R. Newcomb, S. Mohan, and D. M. Cooper Fitness, Training, and the Growth Hormone{->}Insulin-Like Growth Factor I Axis in Prepubertal Girls J. Clin. Endocrinol. Metab., June 1, 2001; 86(6): 2797 - 2802. [Abstract] [Full Text] [PDF]

				R. Dall, K. H. W. Lange, M. Kjær, J. O. L. Jørgensen, J. S. Christiansen, H. Ørskov, and A. Flyvbjerg No Evidence of Insulin-Like Growth Factor-Binding Protein 3 Proteolysis during a Maximal Exercise Test in Elite Athletes J. Clin. Endocrinol. Metab., February 1, 2001; 86(2): 669 - 674. [Abstract] [Full Text]

				M. Lehtonen-Veromaa, T. Möttönen, K. Irjala, I. Nuotio, A. Leino, and J. Viikari A 1-Year Prospective Study on the Relationship between Physical Activity, Markers of Bone Metabolism, and Bone Acquisition in Peripubertal Girls J. Clin. Endocrinol. Metab., October 1, 2000; 85(10): 3726 - 3732. [Abstract] [Full Text]

				H. Yu and T. Rohan Role of the Insulin-Like Growth Factor Family in Cancer Development and Progression J Natl Cancer Inst, September 20, 2000; 92(18): 1472 - 1489. [Abstract] [Full Text] [PDF]

				Growth and Pubertal Development in Elite Female Rhythmic Gymnasts J. Clin. Endocrinol. Metab., December 1, 1999; 84(12): 4525 - 4530. [Abstract] [Full Text]

				A. Eliakim, J. A. Brasel, S. Mohan, W. L. T. Wong, and D. M. Cooper Increased physical activity and the growth hormone-IGF-I axis in adolescent males Am J Physiol Regulatory Integrative Comp Physiol, July 1, 1998; 275(1): R308 - R314. [Abstract] [Full Text] [PDF]

				A. Eliakim, M. Moromisato, D. Moromisato, J. A. Brasel, C. Roberts Jr., and D. M. Cooper Increase in muscle IGF-I protein but not IGF-I mRNA after 5 days of endurance training in young rats Am J Physiol Regulatory Integrative Comp Physiol, October 1, 1997; 273(4): R1557 - R1561. [Abstract] [Full Text] [PDF]