TY - JOUR
T1 - Effects of liquid carbohydrate/essential amino acid ingestion on acute hormonal response during a single bout of resistance exercise in untrained men
AU - Bird, Stephen
AU - Tarpenning, Kyle
AU - Marino, Francesco
N1 - Imported on 10 Apr 2017 - DigiTool details were: Journal title (773t) = Nutrition. ISSNs: 0899-9007;
PY - 2006
Y1 - 2006
N2 - Objective The primary objective of this study was to investigate the influence of nutritive interventions on acute hormonal responses to a single bout of resistance exercise in untrained young men. Specifically, the aim was to determine whether the acute hormonal milieu conducive to enhancing skeletal muscle hypertrophic adaptation to resistance training could be created. The potential role of cortisol in inhibiting training-induced muscle growth is of particular interest, as is whether exercise-induced cortisol release can be attenuated by nutritive interventions. Methods After a 4-h fast, 32 subjects performed a single bout of resistance exercise (not, vert, similar60 min), during which they consumed a 6% carbohydrate (CHO) solution, a 6-g essential amino acid (EAA) mixture, a combined CHO+EAA supplement, or a placebo beverage. Blood samples were collected every 15 min throughout the exercise bout, immediately after exercise, and 15 and 30 min after exercise for analysis of total testosterone, cortisol, growth hormone, insulin, and glucose. Results No significant change in glucose or insulin was observed for placebo. CHO and CHO+EAA ingestion resulted in significantly (P < 0.001) increased glucose and insulin concentrations above baseline, whereas EAA resulted in significant postexercise increases (P < 0.05) in insulin only. Placebo exhibited a significant increase in cortisol within 30 min (P < 0.01), with a peak increase of 105% (P < 0.001) immediately after exercise, and cortisol remained 54% above baseline at 30 min after exercise (P < 0.05). Conversely, the treatment groups displayed no significant change in cortisol during the exercise bout, with CHO and CHO+EAA finishing 27% (P < 0.01) and 23% (P < 0.05), respectively, below baseline at 30 min after exercise. No between-group differences in exercise-induced growth hormone or testosterone concentrations after nutritive intervention were present. Conclusion These data indicate that CHO and/or EAAingestion during a single bout of resistance exercise suppresses the exercise-induced cortisol response, in addition to stimulating insulin release. We conclude that the exercise-induced hormonal profile can be influenced by nutritive interventions toward a profile more favorable for anabolism.
AB - Objective The primary objective of this study was to investigate the influence of nutritive interventions on acute hormonal responses to a single bout of resistance exercise in untrained young men. Specifically, the aim was to determine whether the acute hormonal milieu conducive to enhancing skeletal muscle hypertrophic adaptation to resistance training could be created. The potential role of cortisol in inhibiting training-induced muscle growth is of particular interest, as is whether exercise-induced cortisol release can be attenuated by nutritive interventions. Methods After a 4-h fast, 32 subjects performed a single bout of resistance exercise (not, vert, similar60 min), during which they consumed a 6% carbohydrate (CHO) solution, a 6-g essential amino acid (EAA) mixture, a combined CHO+EAA supplement, or a placebo beverage. Blood samples were collected every 15 min throughout the exercise bout, immediately after exercise, and 15 and 30 min after exercise for analysis of total testosterone, cortisol, growth hormone, insulin, and glucose. Results No significant change in glucose or insulin was observed for placebo. CHO and CHO+EAA ingestion resulted in significantly (P < 0.001) increased glucose and insulin concentrations above baseline, whereas EAA resulted in significant postexercise increases (P < 0.05) in insulin only. Placebo exhibited a significant increase in cortisol within 30 min (P < 0.01), with a peak increase of 105% (P < 0.001) immediately after exercise, and cortisol remained 54% above baseline at 30 min after exercise (P < 0.05). Conversely, the treatment groups displayed no significant change in cortisol during the exercise bout, with CHO and CHO+EAA finishing 27% (P < 0.01) and 23% (P < 0.05), respectively, below baseline at 30 min after exercise. No between-group differences in exercise-induced growth hormone or testosterone concentrations after nutritive intervention were present. Conclusion These data indicate that CHO and/or EAAingestion during a single bout of resistance exercise suppresses the exercise-induced cortisol response, in addition to stimulating insulin release. We conclude that the exercise-induced hormonal profile can be influenced by nutritive interventions toward a profile more favorable for anabolism.
U2 - 10.1016/j.nut.2005.11.005
DO - 10.1016/j.nut.2005.11.005
M3 - Article
SN - 0899-9007
VL - 22
SP - 367
EP - 375
JO - Nutrition
JF - Nutrition
IS - 4
ER -