Branched-chain Amino Acids Supplementation Enhances Exercise Capacity And Lipid Oxidation During Endurance Exercise After Muscle Glycogen Depletion

Effect Increase
Trial Design Double blind
Trial Length 24 hours
Number of Subjects 7
Gender Male
Age Range 18-29
Body Types Average
Notes for this study:
An increase in fat oxidation (with no changes in plasma fatty acids or blood lactate) was noted and thought to be indicative of glycogen preservation in otherwise healthy males subject to prolonged exercise aimed to deplete glycogen. There was also an enhancement of physical performance by 17.2% (time to exhaustion).

Administration Of Branched-chain Amino Acids During Sustained Exercise--effects On Performance And On Plasma Concentration Of Some Amino Acids

Effect Increase
Trial Design Double blind
Trial Length 24 hours
Number of Subjects 218
Gender Both Genders
Body Types Trained, Average
Notes for this study:
Two independent trials (30km cross country run with n=25 and 42.2km marathon with n=193) where BCAA supplementation (50% valine and 30-35% leucine) with some carbohydrates (placebo group also given carbohydrates) at 7.5g (cross country) or 16g (marathon) was able to attenuate post-race fatigue as assessed by the Stroop test. Performance was increased in the slow runners in the marathon, but not in the fast runners.

Administration Of Branched-chain Amino Acids During Sustained Exercise--effects On Performance And On Plasma Concentration Of Some Amino Acids

Effect None
Trial Design Double blind
Trial Length 24 hours
Number of Subjects 218
Gender Both Genders
Body Types Trained, Average
Notes for this study:
Two independent trials (30km cross country run with n=25 and 42.2km marathon with n=193) where BCAA supplementation (50% valine and 30-35% leucine) with some carbohydrates (placebo group also given carbohydrates) at 7.5g (cross country) or 16g (marathon) was able to attenuate post-race fatigue as assessed by the Stroop test. Performance was increased in the slow runners in the marathon, but not in the fast runners.

Ingestion Of Branched-chain Amino Acids And Tryptophan During Sustained Exercise In Man: Failure To Affect Performance

Effect None
Trial Design Double blind
Trial Length 24 hours
Number of Subjects 10
Gender Male
Age Range 18-29
Body Types Trained, Average
Notes for this study:
A cycling exercise at 70-75% VO2 max in trained endurance athletes given 6 or 18g BCAA prior to exercise failed to modify time to exhaustion relative to placebo. Interestingly, 3g tryptophan (thought to reduce performance) also failed in this study.