Branched-Chain Amino Acids Are the Primary Limiting Amino Acids in the Diets of Endurance-Trained Men after a Bout of Prolonged Exercise

Madsen, Klavs, Dave A. MacLean, Bente Kiens, and Dirk Christensen. Effects of glucose, glucose plus branched-chain amino acids, or placebo on bike performance over 100 km. J. Appl. Physiol. 81(6): 2644–2650, 1996.—This study was undertaken to determine the effects of ingesting either glucose ( trial G) or glucose plus branched-chain amino acids (BCAA; trial B), compared with placebo ( trial P), during prolonged exercise. Nine well-trained cyclists with a maximal oxygen uptake of 63.1 ± 1.5 ml O2 ⋅ min−1 ⋅ kg−1performed three laboratory trials consisting of 100 km of cycling separated by 7 days between each trial. During these trials, the subjects were encouraged to complete the 100 km as fast as possible on their own bicycles connected to a magnetic brake. No differences in performance times were observed between the three trials (160.1 ± 4.1, 157.2 ± 4.5, and 159.8 ± 3.7 min, respectively). In trial B, plasma BCAA levels increased from 339 ± 28 μM at rest to 1,026 ± 62 μM after exercise ( P < 0.01). Plasma ammonia concentrations increased during the entire exercise period for all three trials and were significantly higher in trial B compared with trials G and P ( P< 0.05). The respiratory exchange ratio was similar in the three trials during the first 90 min of exercise; thereafter, it tended to drop more in trial P than in trials G and B. These data suggest that neither glucose nor glucose plus BCAA ingestion during 100 km of cycling enhance performance in well-trained cyclists.

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Carbohydrates, Branched-Chain Amino Acids, and Endurances: The Central Fatigue Hypothesis

International Journal of Sport Nutrition ◽

10.1123/ijsn.5.s1.s29 ◽

1995 ◽

Vol 5 (s1) ◽

pp. S29-S38 ◽

Cited By ~ 44

Author(s):

J. Mark Davis

Keyword(s):

Amino Acids ◽

Exercise Performance ◽

Prolonged Exercise ◽

Central Fatigue ◽

Branched Chain Amino Acids ◽

Convincing Evidence ◽

Free Tryptophan ◽

Branched Chain ◽

Sport And Exercise ◽

Exercise Induced

The mechanisms of central fatigue are largely unexplored, but the central fatigue hypothesis suggests that increased brain serotonin (5-HT) can cause a deterioration in sport and exercise performance. There is now convincing evidence that exercise-induced increases in the plasma free tryptophan (f-TRP)/branched-chain amino acids (BCCA) ratio are associated with increased brain 5-HT and the onset of fatigue during prolonged exercise. Furthermore, when drugs are administered to alter brain 5-HT, they have the predicted effects on exercise performance. The influence of nutritional manipulations of f-TRP/BCCA on performance is less well established. The effects of BCCA supplementation on exercise performance are mixed, and the published studies often suffer from methodological flaws. Alternatively, dramatic reductions in f-TRP/BCCA and enhanced performance accompany carbohydrate feedings during prolonged exercise. However, it is difficult to distinguish between the effects of carbohydrate feedings on mechanisms that reside in the brain versus the muscles themselves.

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Supplementation with Branched-Chain Amino Acids (BCAA) and Tryptophan has no Effect on Performance during Prolonged Exercise

Clinical Science ◽

10.1042/cs087s052 ◽

1994 ◽

Vol 87 (s1) ◽

pp. 52-52

Author(s):

G van Hall ◽

JSH Raaymakers ◽

WHM Saris ◽

AJM Wagenmakers

Keyword(s):

Amino Acids ◽

Prolonged Exercise ◽

Branched Chain Amino Acids ◽

Branched Chain

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Plasma amino acid and ammonia responses to altered dietary intakes prior to prolonged exercise in humans

Canadian Journal of Physiology and Pharmacology ◽

10.1139/y92-053 ◽

1992 ◽

Vol 70 (4) ◽

pp. 420-427 ◽

Cited By ~ 10

Author(s):

D. A. MacLean ◽

L. L. Spriet ◽

T. E. Graham

Keyword(s):

Amino Acids ◽

Amino Acid ◽

Prolonged Exercise ◽

Plasma Concentrations ◽

Latin Square ◽

Branched Chain Amino Acids ◽

Dietary Intakes ◽

Rate Of Increase ◽

Branched Chain ◽

Exercise In Humans

This study examined the effects of altered dietary intakes on amino acid and ammonia (NH3) responses prior to and during prolonged exercise in humans. Six male recreational cyclists rode to exhaustion at 75% of [Formula: see text] following 3 days on a low carbohydrate (LC), mixed (M), or high carbohydrate (HC) diet in a latin square design. There were differences (p < 0.05) in exercise times among all treatments (58.8 ± 3.7, 112.1 ± 7.3, and 152.9 ± 10.3 min for the LC, M, and HC treatments, respectively). The rate of increase in plasma NH3 during exercise was greater (p < 0.05) during the LC trial. The LC trial was also characterized by higher (p < 0.05) resting plasma concentrations of branched chain amino acids (BCAA) and a greater decrease in these amino acids during exercise (p < 0.05), as compared with the other two treatments. Both plasma BCAA and NH3 were susceptible to dietary manipulations. These findings suggest that limited carbohydrate availability in association with increased BCAA availability results in enhanced BCAA metabolism during exercise. This is reflected in a greater rate of increase in plasma NH3 and is consistent with the hypothesis that a significant fraction of the NH3 released during a prolonged, submaximal exercise bout is from amino acid catabolism.Key words: AMP deaminase, branched chain amino acids, branched chain keto acid dehydrogenase, glycogen, purine nucleotide cycle.

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Only L-valine among branched-chain amino acids is effective in promoting the growth of the small intestinal mucosa

Gastroenterology ◽

10.1016/s0016-5085(01)83364-3 ◽

2001 ◽

Vol 120 (5) ◽

pp. A676-A676

Author(s):

T TAKAHASHI ◽

H DOI ◽

H KOMATSU ◽

K SATO ◽

O UEDA ◽

...

Keyword(s):

Amino Acids ◽

Intestinal Mucosa ◽

Branched Chain Amino Acids ◽

Small Intestinal Mucosa ◽

Small Intestinal ◽

Branched Chain

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The Weight Loss Effects of Branched Chain Amino Acids and Vitamin B6: A Randomized Controlled Trial on Obese and Overweight Women

International Journal for Vitamin and Nutrition Research ◽

10.1024/0300-9831/a000511 ◽

2018 ◽

Vol 88 (1-2) ◽

pp. 80-89 ◽

Cited By ~ 3

Author(s):

Zahra Shakibay Novin ◽

Saeed Ghavamzadeh ◽

Alireza Mehdizadeh

Keyword(s):

Amino Acids ◽

Weight Loss ◽

Body Composition ◽

Vitamin B6 ◽

Controlled Trial ◽

Density Lipoprotein ◽

Branched Chain Amino Acids ◽

Model Assessment ◽

Waist To Hip Ratio ◽

Branched Chain

Abstract. Branched chain amino acids (BCAA), with vitamin B6 have been reported to improve fat metabolism and muscle synthesis. We hypothesized that supplementation with BCAA and vitamin B6 would result in more weight loss and improve body composition and blood markers related to cardiovascular diseases. Our aim was to determine whether the mentioned supplementation would affect weight loss, body composition, and cardiovascular risk factors during weight loss intervention. To this end, we performed a placebo-controlled randomized clinical trial in 42 overweight and obese women (BMI = 25–34.9 kg/m2). Taking a four-week moderate deficit calorie diet (–500 kcal/day), participants were randomized to receive BCAA (6 g/day) with vitamin B6 (40 mg/day) or placebo. Body composition variables measured with the use of bioelectrical impedance analysis, homeostatic model assessment, and plasma insulin, Low density lipoprotein, High density lipoprotein, Total Cholesterol, Triglyceride, and fasting blood sugar were measured. The result indicated that, weight loss was not significantly affected by BCAA and vitamin B6 supplementation (–2.43 ± 1.02 kg) or placebo (–1.64 ± 1.48 kg). However, significant time × treatment interactions in waist to hip ratio (P = 0.005), left leg lean (P = 0.004) and right leg lean (P = 0.023) were observed. Overall, supplementation with BCAA and vitamin B6 could preserve legs lean and also attenuated waist to hip ratio.

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