Metabolic Response to Provision of Mixed Protein-Carbohydrate Supplementation during Endurance Exercise

2002 ◽  
Vol 12 (4) ◽  
pp. 384-397 ◽  
Author(s):  
Sharon L. Miller ◽  
Carl M. Maresh ◽  
Lawrence E. Armstrong ◽  
Cara B. Ebbeling ◽  
Shannon Lennon ◽  
...  
Keyword(s):  
Amino Acids ◽  
Fatty Acids ◽  
Growth Hormone ◽  
Free Fatty Acids ◽  
Endurance Exercise ◽  
Metabolic Response ◽  
Essential Amino Acids ◽  
Nutritional Supplementation ◽  
Post Exercise ◽  
Branched Chain

The interaction of substrates and hormones in response to ingestion of intact proteins during endurance exercise is unknown. This study characterized substrate and hormone responses to supplementation during endurance exercise. Nine male runners participated in 3 trials in which a non-fat (MILK), carbohydrate (CHO), or placebo (PLA) drink was consumed during a 2-hour treadmill >· run at 65% V̇O2max. Circulating levels of insulin, glucagon, epinephrine, norepi-nephrine, growth hormone, testosterone, and cortisol were measured. Plasma substrates included glucose, lactate, free fatty acids, and select amino acids. Except for insulin and cortisol, hormones increased with exercise. While post-exercise insulin concentrations declined similarly in all 3 trials, the glucagon increase was greatest following MILK consumption. CHO blunted the post-exercise increase in growth hormone compared to levels in MILK. Free fatty acids and plasma amino acids also were responsive to nutritional supplementation with both CHO and MILK attenuating the rise in free fatty acids compared to the increase observed in PLA. Correspondingly, respiratory exchange ratio increased during CHO. Essential amino acids increased significantly only after MILK and were either unchanged or decreased in CHO. PLA was characterized by a decrease in branched-chain amino acid concentrations. Modest nutritional supplementation in this study altered the endocrine response as well as substrate availability and utilization following and during an endurance run, respectively.

The Metabolic Response of Glycogen and Free Fatty Acids to Endurance Exercise

2017 ◽  
Vol 5 (1) ◽  
pp. 68-75
Author(s):  
Piero Ipata ◽  
Francesco Balestri ◽  
Rossana Pesi
Keyword(s):  
Fatty Acids ◽  
Free Fatty Acids ◽  
Endurance Exercise ◽  
Metabolic Response

Influence Of Branched-chain Aminoacids (BCAA) Supplementation On Free Fatty Acids Oxidation During Endurance Exercise After Muscle Glycogen Depletion

2005 ◽  
Vol 37 (Supplement) ◽  
pp. S349
Author(s):  
Thomas B. Adolpho ◽  
Patr??cia Lopes Campos ◽  
Bruno Gualano ◽  
Josilene Carla Gomes ◽  
Fernanda Baeza Scagliusi ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Free Fatty Acids ◽  
Endurance Exercise ◽  
Muscle Glycogen ◽  
Glycogen Depletion ◽  
Branched Chain

Influence Of Branched-chain Aminoacids (BCAA) Supplementation On Free Fatty Acids Oxidation During Endurance Exercise After Muscle Glycogen Depletion

2005 ◽  
Vol 37 (Supplement) ◽  
pp. S349
Author(s):  
Thomas B. Adolpho ◽  
Patrícia Lopes Campos ◽  
Bruno Gualano ◽  
Josilene Carla Gomes ◽  
Fernanda Baeza Scagliusi ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Free Fatty Acids ◽  
Endurance Exercise ◽  
Muscle Glycogen ◽  
Glycogen Depletion ◽  
Branched Chain

scholarly journals Modulation of basal glucose metabolism and insulin sensitivity by growth hormone and free fatty acids during short-term fasting

2004 ◽  
pp. 779-787 ◽  
Author(s):  
H Norrelund ◽  
S Nielsen ◽  
JS Christiansen ◽  
JO Jorgensen ◽  
N Moller
Keyword(s):  
Fatty Acids ◽  
Growth Hormone ◽  
Glucose Metabolism ◽  
Free Fatty Acids ◽  
Metabolic Response ◽  
Normal Subjects ◽  
Glucose Turnover ◽  
Antagonistic Effects ◽  
Gh Replacement ◽  
Stimulation Of

BACKGROUND AND AIMS: The metabolic response to fasting involves an increase in circulating levels of growth hormone (GH) and free fatty acids, and resistance to insulin's actions on glucose metabolism. Stimulation of lipolysis and insulin resistance are well-described effects of GH. The present study was designed to test the degree to which the insulin antagonistic effects of GH on glucose metabolism are mediated through stimulation of lipolysis during fasting. METHODS: Seven normal subjects were examined on three occasions during a 40-h fast with infusion of somatostatin, insulin and glucagon for the final 18 h: (expt. i) with GH replacement, (expt. ii) with GH replacement and antilipolysis with acipimox, and (expt. iii) without GH and with antilipolysis. RESULTS: Basal glucose turnover was significantly reduced by addition of acipimox (rate of disappearance (Rd) glucose (mg/kg/min): 1.91+/-0.08 (expt. i), 1.69+/-0.05 (expt. ii), 1.61+/-0.08 (expt. iii); P<0.01), whereas insulin-stimulated glucose uptake was significantly increased (glucose infusion rate (M-value) (mg/kg/min): 1.66+/-0.22 (expt. i), 2.47+/-0.10 (expt. ii), 2.00+/-0.31 (expt. iii); P<0.05). Addition of GH during inhibition of lipolysis failed to affect basal and insulin-stimulated glucose metabolism significantly. CONCLUSION: Thus, the present data provide strong evidence that the insulin antagonistic effects of GH on fasting glucose metabolism are causally linked to concomitant stimulation of lipolysis.

Effect of Exercise Intensity on Free Tryptophan to Branched-Chain Amino Acids Ratio and Plasma Prolactin During Endurance Exercise

1997 ◽  
Vol 22 (3) ◽  
pp. 280-291 ◽  
Author(s):  
Heiko K. Strüder ◽  
Wildor Hollmann ◽  
Petra Platen ◽  
Ronny Wöstmann ◽  
Alexander Ferrauti ◽  
...  
Keyword(s):  
Amino Acids ◽  
Fatty Acids ◽  
Free Fatty Acids ◽  
Endurance Exercise ◽  
Exercise Duration ◽  
Cycle Ergometer ◽  
Plasma Prolactin ◽  
Free Tryptophan ◽  
Energy Bar ◽  
Intensity Of Exercise

The potential of exercise-induced changes in peripheral amino acids to alter blood prolactin levels through a seratonergic system modification was investigated in 8 male athletes. In two trials, subjects (N = 8) exercised on a cycle ergometer for 5 hr. The intensity of exercise corresponded to 55% VO2max (T55) or 75% VO2max (T75) respectively. In each trial, each subject received a 25-g energy bar (111 kcal) every 60 min, as well as 300 ml of a 6% carbohydrate solution (90 kcal) every 30 min of exercise duration. Plasma glucose and insulin declined (p ≤.05) in both trials during exercise. Ammonia was augmented (p ≤.05) above the baseline concentration after 120 min in both trials. During the last 2 hr of exercise, plasma free fatty acids were higher (p ≤.05) in T75, than in T55. During this time, the plasma free TRP/BCAA ratio was also augmented (p ≤.05) in T75 while no change was induced in T55. Plasma prolactin did not change in T55, while an increase (p ≤.05) was found in T75. The findings may further support the hypothesis that during endurance exercise changes in peripheral amino acid concentration may influence prolactin response via serotonergic system modifications. Key words: blood-brain barrier, serotonin, neuroendocrine system, free fatty acids, ammonia

The metabolism of glucose, acetate, lipids and amino acids in lactating dairy cows

1974 ◽  
Vol 82 (1) ◽  
pp. 71-85 ◽  
Author(s):  
R. Bickerstaffe ◽  
E. F. Annison ◽  
J. L. Linzell
Keyword(s):  
Amino Acids ◽  
Fatty Acids ◽  
Free Fatty Acids ◽  
Dairy Cows ◽  
Milk Protein ◽  
Essential Amino Acids ◽  
Milk Fatty Acids ◽  
Plasma Triglycerides ◽  
A Chain ◽  
Arteriovenous Difference

SUMMARYSpecialized techniques, previously used in surgically prepared goats, which simultaneously measure udder metabolism (arteriovenous difference of milk precursors x udder blood flow) and the whole body turnover of the milk precursors, have been successfully transferred to dairy cows. Methods of obtaining representative samples of arterial and mammary venous blood and of measuring udder blood flow are described.The rates of entry into the circulation, as determined by isotope dilution, of glucose, acetate and plasma free fatty acids were 3·3–4·0, 1·7–2·1 and 0·5 kg/day respectively. Acetate and glucose contributed 32–50 and 4–11% respectively of the total CO2output by the animal.Measurement of the uptake of precursors of milk constituents and their transfer into milk showed that there were substantial arteriovenous differences of glucose, acetate, triglyceride and β-hydroxybutyrate which were not significantly different between breeds or related to milk yield. Isotopic and balance data confirm that glucose is the main precursor of lactose and that the oxidation and transfer of glucose into lactose accounted for 69–98% of the glucose entry rate. As in the goat, plasma triglycerides and blood acetate accounted for 35–80% and 25–50% of the milk triglycerides respectively. Propionate was extracted from plasma but the uptake was only about 8% of the value for acetate.There was no net arteriovenous difference of phospholipids, cholesterol esters or free fatty acids, but the fall in specific radioactivity of free fatty acids across the mammary gland indicated there was an exchange of free fatty acids between plasma and mammary tissue. In agreement with previous findings, acetate contributed to all the milk fatty acids up to a chain length of C14 and part of the C16 fatty acid. Plasma triglycerides contributed to the remainder of the C16 fatty acid and all the milk fatty acids with a chain length of C18 or higher.In contrast to the lactating goat, cow plasma contained very few chylomicrons. The majority of the triglycerides taken up by the udder were derived from the lowdensity lipoprotein fraction.The essential amino acids were extracted from blood in amounts sufficient to account for the essential amino acids secreted into milk protein. Although the plasma level of methionine was low, 52–72% of the material reaching the mammary gland was taken up. The uptake of arginine was far in excess of the requirement for milk protein synthesis.

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