Journal of Clinical Biochemistry and Nutrition
Online ISSN : 1880-5086
Print ISSN : 0912-0009
ISSN-L : 0912-0009
Original Articles
Effects of Citric Acid and L-Carnitine on Physical Fatigue
Tomohiro SuginoSayaka AoyagiTomoko ShiraiYoshitaka KajimotoOsami Kajimoto
ジャーナル フリー

2007 年 41 巻 3 号 p. 224-230


We examined the effects of citric acid and L-carnitine administration on physical fatigue. In a double-blind, placebo-controlled, 3-way crossover study, 18 healthy volunteers were randomized to oral citric acid (2,700 mg/day), L-carnitine (1,000 mg/day), or placebo for 8 days. The fatigue-inducing physical task consisted of workload trials on a cycle ergometer at fixed workloads for 2 h on 2 occasions. Before the physical load, salivary chromogranin A, measured as a physiological stress marker, was lower in the group given citric acid than in the group given placebo. Also, after the physical load, the subjective feeling of fatigue assessed with a visual analogue scale was lower in the citric acid group than in the placebo group. In contrast, L-carnitine had no effect on chromogranin A or subjective fatigue. These results suggest that citric acid reduces physiological stress and attenuates physical fatigue, whereas L-carnitine does not.

© 2007 by The Editorial Secretariat of JCBN