Journal of Applied Physiology, Vol 79, Issue 4 1100-1105, Copyright © 1995 by American Physiological Society

ARTICLES

Pancreatic islet insulin secretion is increased after resistance exercise in rats

J. D. Fluckey, W. J. Kraemer and P. A. Farrell
Noll Physiological Research Center, Pennsylvania State University, University Park 16802, USA.

The purpose of this study was to determine whether 4 days of resistance exercise facilitated insulin secretory adaptations at the level of the pancreatic islets. Eighteen male 400-g Sprague-Dawley rats were randomly assigned to two groups. All animals were operantly conditioned to engage in a resistance exercise protocol that required full extension of the hindlimbs. Resistance was applied to the animals via a leather-and-Velcro vest to which weighted pouches were attached. The acute (Acute, n = 9) group engaged in four exercise sessions (50 reps each) with increased resistance for each session (70-->120-->120-->190 g). Sessions were separated by 48 h of rest. The nonexercised (Nonex, n = 9) group engaged in the same protocol without resistance. Islets were dispersed 16 h postexercise, incubated for 48 h, and perifused (17-20 islets/rat) with a medium containing 10 mM L-arginine or 16 mM glucose as the insulin secretagogue. Basal insulin secretion from the islets before the introduction of L-arginine or 16 mM glucose was the same for the Acute and Nonex groups (P > 0.05). The total insulin response to 10 mM arginine was significantly higher for the Acute than for the Nonex group (1.16 +/- 0.30 and 0.31 +/- 0.10 ng insulin.islet-1.25 min-1, respectively, P < 0.05). There were no differences between groups for the overall insulin response to glucose (P > 0.05). However, the late-phase insulin response to glucose was higher for the Acute group (P < 0.05). These data suggest that insulin secretory adaptations occur at the level of the pancreatic islets after 4 days of resistance exercise.

This article has been cited by other articles:

				W. J. Evans Protein Nutrition, Exercise and Aging J. Am. Coll. Nutr., December 1, 2004; 23(suppl_6): 601S - 609S. [Abstract] [Full Text] [PDF]

				O. Wirth, E. W. Gregory, R. G. Cutlip, and G. R. Miller Control and quantitation of voluntary weight-lifting performance of rats J Appl Physiol, July 1, 2003; 95(1): 402 - 412. [Abstract] [Full Text] [PDF]

				J. C. Kostyak, S. R. Kimball, L. S. Jefferson, and P. A. Farrell Severe diabetes inhibits resistance exercise-induced increase in eukaryotic initiation factor 2B activity J Appl Physiol, July 1, 2001; 91(1): 79 - 84. [Abstract] [Full Text] [PDF]

				M. J. Fedele, C. H. Lang, and P. A. Farrell Immunization against IGF-I prevents increases in protein synthesis in diabetic rats after resistance exercise Am J Physiol Endocrinol Metab, June 1, 2001; 280(6): E877 - E885. [Abstract] [Full Text] [PDF]

				E. T. Poehlman, A. Turturro, N. Bodkin, W. Cefalu, S. Heymsfield, J. Holloszy, and J. Kemnitz Caloric Restriction Mimetics: Physical Activity and Body Composition Changes J. Gerontol. A Biol. Sci. Med. Sci., March 1, 2001; 56(90001): 45 - 54. [Abstract] [Full Text] [PDF]

				P. A. Farrell, J. M. Hernandez, M. J. Fedele, T. C. Vary, S. R. Kimball, and L. S. Jefferson Eukaryotic initiation factors and protein synthesis after resistance exercise in rats J Appl Physiol, March 1, 2000; 88(3): 1036 - 1042. [Abstract] [Full Text] [PDF]

				J. M. Hernandez, M. J. Fedele, and P. A. Farrell Time course evaluation of protein synthesis and glucose uptake after acute resistance exercise in rats J Appl Physiol, March 1, 2000; 88(3): 1142 - 1149. [Abstract] [Full Text] [PDF]

				M. J. Fedele, J. M. Hernandez, C. H. Lang, T. C. Vary, S. R. Kimball, L. S. Jefferson, and P. A. Farrell Severe diabetes prohibits elevations in muscle protein synthesis after acute resistance exercise in rats J Appl Physiol, January 1, 2000; 88(1): 102 - 108. [Abstract] [Full Text] [PDF]

				P. A. Farrell, M. J. Fedele, J. Hernandez, J. D. Fluckey, J. L. Miller III, C. H. Lang, T. C. Vary, S. R. Kimball, and L. S. Jefferson Hypertrophy of skeletal muscle in diabetic rats in response to chronic resistance exercise J Appl Physiol, September 1, 1999; 87(3): 1075 - 1082. [Abstract] [Full Text] [PDF]

				P. A. Farrell, M. J. Fedele, T. C. Vary, S. R. Kimball, C. H. Lang, and L. S. Jefferson Regulation of protein synthesis after acute resistance exercise in diabetic rats Am J Physiol Endocrinol Metab, April 1, 1999; 276(4): E721 - E727. [Abstract] [Full Text] [PDF]

				P. A. Farrell, M. J. Fedele, T. C. Vary, S. R. Kimball, and L. S. Jefferson Effects of intensity of acute-resistance exercise on rates of protein synthesis in moderately diabetic rats J Appl Physiol, December 1, 1998; 85(6): 2291 - 2297. [Abstract] [Full Text] [PDF]