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Medical AI Inquiry: You was designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.  Labels: OBJECTIVE, METHODS, RESULTS. Meshes: Adult, Analysis of Variance, Basal Metabolism, Carnitine, Exercise, Fatty Acids, Female, Humans, Male, Middle Aged, Obesity, Rest, Statistics, Nonparametric.
user
Does [ The supplementation of L-carnitine promote alterations in the resting metabolic rate and in the use of energetic substrates in physically active individuals ]? Context: 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. 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. 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.
assistant
Supplementation with L-carnitine caused no changes in the variables analyzed in this study. Final Decision: no