[The supplementation of L-carnitine does not promote alterations in the resting metabolic rate and in the use of energetic substrates in physically active individuals].
OBJECTIVE
To investigate the effects of L-carnitine supplementation, over thirty days, on the resting metabolic rate (RMR) and oxidation of free fatty acids (FFA) under rested or exercised conditions.


METHODS
Twenty-one overweight active volunteers (40 to 58 years old) were randomized into two groups: supplemented (GS; N = 11; 1,8 g/day of L-carnitine) or placebo (GP; N = 10; maltodextrin). Caloric intake, anthropometry, RMR, VO(2max), respiratory exchange ratio and plasma FFA were measured.


RESULTS
No significant changes were found in the caloric intake (-244,66 vs. -126,00 kcal/day), body composition (-0.07 vs. -0.17 kg/m(2)), RMR (0.06 vs. -0.02 kcal/day), respiratory exchange ratio at rest (3.69 vs. -1.01) and exercise (0.01 vs. -0.01) or VO(2max) (0.50 vs. 1.25 mL/kg/min) between GS and GP. Plasma FFA levels were increased under resting conditions only in the GP group (0.27), but no significant changes were observed before or after physical activity in any of the groups.


CONCLUSIONS
Supplementation with L-carnitine caused no changes in the variables analyzed in this study.
Faria Coelho
Christianne de
Cd
Programa de Pós-graduação em Nutrição Humana Aplicada, Universidade de São Paulo, Brasil. christianne.coelho@hotmail.com
Mota
João Felipe
JF
Paula Ravagnani
Fabrício César de
FC
Burini
Roberto Carlos
RC
D000328:Adult; D000704:Analysis of Variance; D001481:Basal Metabolism / Q000187:drug effects* / Q000502:physiology; D002331:Carnitine / Q000008:administration & dosage*; D015444:Exercise / Q000502:physiology*; D005227:Fatty Acids / Q000378:metabolism*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000188:drug therapy*; D012146:Rest / Q000502:physiology*; D018709:Statistics, Nonparametric
D005227:Fatty Acids; D002331:Carnitine