PMID- 20386134
OWN - NLM
STAT- MEDLINE
DCOM- 20110506
LR  - 20161018
IS  - 1533-4287 (Electronic)
IS  - 1064-8011 (Linking)
VI  - 25
IP  - 2
DP  - 2011 Feb
TI  - Branched-chain amino acid supplementation lowers perceived exertion but does not 
      affect performance in untrained males.
PG  - 539-44
LID - 10.1519/JSC.0b013e3181bf443a [doi]
AB  - The purpose of this study was to determine whether branched-chain amino acid 
      (BCAA) supplementation affects aerobic performance, ratings of perceived exertion 
      (RPE), or substrate utilization as compared with an isocaloric, carbohydrate 
      (CHO) beverage or a noncaloric placebo (PLAC) beverage. Nine untrained males 
      performed three 90-minute cycling bouts at 55% VO(2) peak followed by 15-minute 
      time trials. Subjects, who were blinded to beverage selection, ingested a total 
      of 200 kcal via the CHO or BCAA beverage before and at 60 minutes of exercise or 
      the PLAC beverage on the same time course. RPE and metabolic measurements were 
      taken every 15 minutes during steady-state exercise, and each of the trials was 
      separated by 8 weeks. Plasma glucose and BCAA concentrations were measured pre- 
      and post-exercise. A greater distance (4.6 +/- 0.6 km) was traveled in the 
      time-trial during the CHO trial than the PLAC trial (3.9 +/- 0.4 km) (p < 0.05). 
      There was no difference between the BCAA (4.4 +/- 0.5 km) and PLAC trials. RPE was 
      reduced at the 75-minute and 90-minute mark during the BCAA trial as compared 
      with the PLAC trial. There were no significant differences found for the trial 
      vs. time interaction in regard to respiratory exchange ratio. Thus, CHO 
      supplementation improves performance in a loaded time-trial as compared with a 
      PLAC beverage. BCAA supplementation, although effective at increasing blood 
      concentrations of BCAA, did not influence aerobic performance but did attenuate 
      RPE as compared with a PLAC beverage.
FAU - Greer, Beau Kjerulf
AU  - Greer BK
AD  - Department of Physical Therapy and Human Movement Sciences, Sacred Heart 
      University, Fairfield, CT, USA. greerb@sacredheart.edu
FAU - White, Jim P
AU  - White JP
FAU - Arguello, Eric M
AU  - Arguello EM
FAU - Haymes, Emily M
AU  - Haymes EM
LA  - eng
PT  - Comparative Study
PT  - Journal Article
PT  - Randomized Controlled Trial
PL  - United States
TA  - J Strength Cond Res
JT  - Journal of strength and conditioning research
JID - 9415084
RN  - 0 (Amino Acids, Branched-Chain)
RN  - 0 (Carbohydrates)
SB  - IM
MH  - Amino Acids, Branched-Chain/*administration & dosage/metabolism
MH  - Anaerobic Threshold/*drug effects
MH  - Analysis of Variance
MH  - Bicycling/*physiology
MH  - Carbohydrates/*administration & dosage
MH  - Dietary Supplements
MH  - Energy Metabolism
MH  - Humans
MH  - Male
MH  - Muscle Fatigue/drug effects
MH  - Muscle, Skeletal/drug effects
MH  - Oxygen Consumption/physiology
MH  - Physical Endurance/drug effects
MH  - Physical Exertion/*drug effects
MH  - Reference Values
MH  - Single-Blind Method
MH  - Young Adult
EDAT- 2010/04/14 06:00
MHDA- 2011/05/07 06:00
CRDT- 2010/04/14 06:00
PHST- 2010/04/14 06:00 [entrez]
PHST- 2010/04/14 06:00 [pubmed]
PHST- 2011/05/07 06:00 [medline]
AID - 10.1519/JSC.0b013e3181bf443a [doi]
PST - ppublish
SO  - J Strength Cond Res. 2011 Feb;25(2):539-44. doi: 10.1519/JSC.0b013e3181bf443a.