TY - JOUR
T1 - Glucoregulatory responses to intense exercise performed in the postprandial state
AU - Kreisman, Stuart H.
AU - Manzon, Anthony
AU - Nessim, Sharon J.
AU - Morais, José A.
AU - Gougeon, Réjeanne
AU - Fisher, Simon J.
AU - Vranic, Mladen
AU - Marliss, Errol B.
PY - 2000/5
Y1 - 2000/5
N2 - A seven- to eightfold increment in hepatic glucose production (endogenous R(a)) occurs in postabsorptive (PA) intense exercise (IE). A similar response is likely present in the postprandial (PP) state, when most such exercise is performed, because 1) little evidence for increased intestinal absorption of glucose during exercise exists, and 2) intravenous glucose does not prevent it. We investigated IE in 10 PA and 8 PP fit, lean, young males who had exercised for 15 min at >84% maximum O2 uptake, starting 3 h after a 412-kcal mixed meal. The meal induced a small rise in glycemia with sustained insulin and glucagon increases. Preexercise glucose total R(a) and utilization (R(a)) were equal and ~130% of the PA level. Exercise hyperglycemia in PP was delayed and diminished and, in early recovery, was of shorter duration and lesser magnitude (P = 0.042). Peak catecholamine (12- to 16-fold increase) and R(a) (PP: 11.5 ± 1.4, PA: 13.8 ± 1.4 mg·kg- 1·min-1) responses did not differ, and their responses during exercise were significantly correlated. Exercise glucagon, insulin, and glucagon-to- insulin responses were small or not significant. R(d) reached the same peak (PP: 8.0 ± 0.6, PA: 9.3 ± 0.8 mg·kg-1·min-1) but was greater at 20- 120 min of recovery in PP (P = 0.001). Therefore, the total R(a) response to IE is preserved despite the possibility of prior PP suppression of endogenous R(a) and is consistent with catecholamine mediation. Post-IE hyperglycemia is reduced in the postprandial state.
AB - A seven- to eightfold increment in hepatic glucose production (endogenous R(a)) occurs in postabsorptive (PA) intense exercise (IE). A similar response is likely present in the postprandial (PP) state, when most such exercise is performed, because 1) little evidence for increased intestinal absorption of glucose during exercise exists, and 2) intravenous glucose does not prevent it. We investigated IE in 10 PA and 8 PP fit, lean, young males who had exercised for 15 min at >84% maximum O2 uptake, starting 3 h after a 412-kcal mixed meal. The meal induced a small rise in glycemia with sustained insulin and glucagon increases. Preexercise glucose total R(a) and utilization (R(a)) were equal and ~130% of the PA level. Exercise hyperglycemia in PP was delayed and diminished and, in early recovery, was of shorter duration and lesser magnitude (P = 0.042). Peak catecholamine (12- to 16-fold increase) and R(a) (PP: 11.5 ± 1.4, PA: 13.8 ± 1.4 mg·kg- 1·min-1) responses did not differ, and their responses during exercise were significantly correlated. Exercise glucagon, insulin, and glucagon-to- insulin responses were small or not significant. R(d) reached the same peak (PP: 8.0 ± 0.6, PA: 9.3 ± 0.8 mg·kg-1·min-1) but was greater at 20- 120 min of recovery in PP (P = 0.001). Therefore, the total R(a) response to IE is preserved despite the possibility of prior PP suppression of endogenous R(a) and is consistent with catecholamine mediation. Post-IE hyperglycemia is reduced in the postprandial state.
KW - Catecholamines
KW - Glucagon
KW - Glucose turnover
KW - Insulin
KW - Postprandial exercise
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U2 - 10.1152/ajpendo.2000.278.5.e786
DO - 10.1152/ajpendo.2000.278.5.e786
M3 - Article
C2 - 10780933
AN - SCOPUS:0342804534
SN - 0193-1849
VL - 278
SP - E786-E793
JO - American Journal of Physiology - Endocrinology and Metabolism
JF - American Journal of Physiology - Endocrinology and Metabolism
IS - 5 41-5
ER -