Journal of Applied Physiology, Vol 61, Issue 5 1693-1700, Copyright © 1986 by American Physiological Society

ARTICLES

Increased epinephrine response and inaccurate glucoregulation in exercising athletes

M. Kjaer, P. A. Farrell, N. J. Christensen and H. Galbo

Epinephrine responses to insulin-induced hypoglycemia have indicated that athletes have a higher adrenal medullary secretory capacity than untrained subjects. This view was tested by an exercise protocol aiming at identical stimulation of the adrenal medulla in the two groups. Eight athletes (T) and eight controls (C) ran 7 min at 60% maximal O2 consumption (VO2max), 3 min at 100% VO2max, and 2 min at 110% VO2max. Plasma epinephrine both at rest and at identical relative work loads [110% VO2max: 8.73 +/- 1.51 (T) vs. 3.60 +/- 1.09 mmol X l-1 (C)] was higher [P less than 0.05) in T than in C. Norepinephrine, as well as heart rate, increased identically in the two groups, indicating identical sympathetic nervous activity. Lactate and glycerol were higher in T than in C after running. Glucose production peaked immediately after exercise and was higher in T than in C. Glucose disappearance increased less than glucose production and was identical in T and C. Accordingly plasma glucose increased, more in T than in C (P less than 0.01). In T glucose levels approached the renal threshold greater than 20 min postexercise. Glucose clearance increased less in T than in C during exercise and decreased postexercise to or below (T, P less than 0.05) basal levels, despite increased insulin levels. Long-term endurance training increases responsiveness of the adrenal medulla to exercise, indicating increased secretory capacity. During maximal exercise this may contribute to higher glucose production, lower clearance, more inaccurate glucoregulation, and higher lypolysis in T compared with C.

This article has been cited by other articles:

				F. N. Daussin, J. Zoll, E. Ponsot, S. P. Dufour, S. Doutreleau, E. Lonsdorfer, R. Ventura-Clapier, B. Mettauer, F. Piquard, B. Geny, et al. Training at high exercise intensity promotes qualitative adaptations of mitochondrial function in human skeletal muscle J Appl Physiol, May 1, 2008; 104(5): 1436 - 1441. [Abstract] [Full Text] [PDF]

				D. R. Broom, D. J. Stensel, N. C. Bishop, S. F. Burns, and M. Miyashita Exercise-induced suppression of acylated ghrelin in humans J Appl Physiol, June 1, 2007; 102(6): 2165 - 2171. [Abstract] [Full Text] [PDF]

				C. C. Dunbar, J. T. Kassotis, E. K. Heyda, B. I. Saul, A. Khan, and J. Gelles Repetitive Monomorphic Ventricular Tachycardia Associated with Exercise: A Case Report Angiology, September 1, 2005; 56(5): 631 - 635. [Abstract] [PDF]

				M. E. Wall, J. E. Faber, X. Yang, M. Tsuzaki, and A. J. Banes Norepinephrine-induced calcium signaling and expression of adrenoceptors in avian tendon cells Am J Physiol Cell Physiol, October 1, 2004; 287(4): C912 - C918. [Abstract] [Full Text] [PDF]

				S. H. Kreisman, J. B. Halter, M. Vranic, and E. B. Marliss Combined Infusion of Epinephrine and Norepinephrine During Moderate Exercise Reproduces the Glucoregulatory Response of Intense Exercise Diabetes, June 1, 2003; 52(6): 1347 - 1354. [Abstract] [Full Text] [PDF]

				S.-H. Suh, G. A. Casazza, M. A. Horning, B. F. Miller, and G. A. Brooks Effects of oral contraceptives on glucose flux and substrate oxidation rates during rest and exercise J Appl Physiol, January 1, 2003; 94(1): 285 - 294. [Abstract] [Full Text] [PDF]

				R. R. Kraemer, H. Chu, and V. D. Castracane Leptin and Exercise Experimental Biology and Medicine, October 1, 2002; 227(9): 701 - 708. [Abstract] [Full Text] [PDF]

				S.-H. Suh, G. A. Casazza, M. A. Horning, B. F. Miller, and G. A. Brooks Luteal and follicular glucose fluxes during rest and exercise in 3-h postabsorptive women J Appl Physiol, July 1, 2002; 93(1): 42 - 50. [Abstract] [Full Text] [PDF]

				J. F. P. Wojtaszewski, J. N. Nielsen, and E. A. Richter Exercise Effects on Muscle Insulin Signaling and Action: Invited Review: Effect of acute exercise on insulin signaling and action in humans J Appl Physiol, July 1, 2002; 93(1): 384 - 392. [Abstract] [Full Text] [PDF]

				E. B. Marliss and M. Vranic Intense Exercise Has Unique Effects on Both Insulin Release and Its Roles in Glucoregulation: Implications for Diabetes Diabetes, February 1, 2002; 51(90001): S271 - 283. [Abstract] [Full Text] [PDF]

				R. H. Coker, L. Simonsen, J. Bulow, D. H. Wasserman, and M. Kjar Stimulation of splanchnic glucose production during exercise in humans contains a glucagon-independent component Am J Physiol Endocrinol Metab, June 1, 2001; 280(6): E918 - E927. [Abstract] [Full Text] [PDF]

				S. H. Kreisman, N. Ah Mew, J. B. Halter, M. Vranic, and E. B. Marliss Norepinephrine Infusion during Moderate-Intensity Exercise Increases Glucose Production and Uptake J. Clin. Endocrinol. Metab., May 1, 2001; 86(5): 2118 - 2124. [Abstract] [Full Text]

				S. H. Kreisman, A. Manzon, S. J. Nessim, J. A. Morais, R. Gougeon, S. J. Fisher, M. Vranic, and E. B. Marliss Glucoregulatory responses to intense exercise performed in the postprandial state Am J Physiol Endocrinol Metab, May 1, 2000; 278(5): E786 - E793. [Abstract] [Full Text] [PDF]

				S. H. Kreisman, N. A. Mew, M. Arsenault, S. J. Nessim, J. B. Halter, M. Vranic, and E. B. Marliss Epinephrine infusion during moderate intensity exercise increases glucose production and uptake Am J Physiol Endocrinol Metab, May 1, 2000; 278(5): E949 - E957. [Abstract] [Full Text] [PDF]

				E. B. Marliss, S. H. Kreisman, A. Manzon, J. B. Halter, M. Vranic, and S. J. Nessim Gender differences in glucoregulatory responses to intense exercise J Appl Physiol, February 1, 2000; 88(2): 457 - 466. [Abstract] [Full Text] [PDF]

				R. J. Sigal, S. J. Fisher, J. B. Halter, M. Vranic, and E. B. Marliss Glucoregulation during and after Intense Exercise: Effects of {beta}-Adrenergic Blockade in Subjects with Type 1 Diabetes Mellitus J. Clin. Endocrinol. Metab., November 1, 1999; 84(11): 3961 - 3971. [Abstract] [Full Text]

				C. J. Pritzlaff, L. Wideman, J. Y. Weltman, R. D. Abbott, M. E. Gutgesell, M. L. Hartman, J. D. Veldhuis, and A. Weltman Impact of acute exercise intensity on pulsatile growth hormone release in men J Appl Physiol, August 1, 1999; 87(2): 498 - 504. [Abstract] [Full Text] [PDF]

				M. Kjar, B. Hanel, L. Worm, G. Perko, S. F. Lewis, K. Sahlin, H. Galbo, and N. H. Secher Cardiovascular and neuroendocrine responses to exercise in hypoxia during impaired neural feedback from muscle Am J Physiol Regulatory Integrative Comp Physiol, July 1, 1999; 277(1): R76 - R85. [Abstract] [Full Text] [PDF]

				A. L. Friedlander, G. A. Casazza, M. A. Horning, M. J. Huie, M. F. Piacentini, J. K. Trimmer, and G. A. Brooks Training-induced alterations of carbohydrate metabolism in women: women respond differently from men J Appl Physiol, September 1, 1998; 85(3): 1175 - 1186. [Abstract] [Full Text] [PDF]

				A. Manzon, S. J. Fisher, J. A. Morais, L. Lipscombe, M.-C. Guimond, S. J. Nessim, R. J. Sigal, J. B. Halter, M. Vranic, and E. B. Marliss Glucose infusion partially attenuates glucose production and increases uptake during intense exercise J Appl Physiol, August 1, 1998; 85(2): 511 - 524. [Abstract] [Full Text] [PDF]

				P. Del Corral, E. T. Howley, M. Hartsell, M. Ashraf, and M. S. Younger Metabolic effects of low cortisol during exercise in humans J Appl Physiol, March 1, 1998; 84(3): 939 - 947. [Abstract] [Full Text] [PDF]

				A. L. Friedlander, G. A. Casazza, M. A. Horning, M. J. Huie, and G. A. Brooks Training-induced alterations of glucose flux in men J Appl Physiol, April 1, 1997; 82(4): 1360 - 1369. [Abstract] [Full Text] [PDF]

				D. Gozal, P. Thiriet, J. M. Cottet-Emard, D. Wouassi, E. Bitanga, A. Geyssant, J. M. Pequignot, and M. Sagnol Glucose administration before exercise modulates catecholaminergic responses in glycogen-depleted subjects J Appl Physiol, January 1, 1997; 82(1): 248 - 256. [Abstract] [Full Text] [PDF]