Decrease in Respiratory Quotient During Exercise Following L-Carnitine Supplementation
- 1 February 1989
- journal article
- research article
- Published by Georg Thieme Verlag KG in International Journal of Sports Medicine
- Vol. 10 (03) , 169-174
- https://doi.org/10.1055/s-2007-1024895
Abstract
This study was undertaken to determine the effects of L-carnitine addition to the diet during submaximal exercise in endurance-trained humans. Ten subjects (V̇O2max; 62 ml·kg-1·min-1) performed a control test (C) (45 min of cycling at 66% of V̇O2max) followed by 60 min of recovery in a sitting position. Each subject repeated this trial after 28 days of placebo (P) and L-carnitine (L-C) treatment (double-blinded cross-over design). The dose of each treatment was 2 g/day. There were no differences between the C and P tests. The respiratory quotient was lower (p < 0.05) with treatment than with P or C during exercise. In addition, oxygen uptake, heart rate, blood glycerol, and resting plasma free fatty acid concentrations presented a nonsignificant trend toward higher values in L-C than in the C or P groups. These observations suggest an increased lipid utilization by muscle during exercise in the L-C-treated group. This effect has further possibilities for improving performance during submaximal exercise.Keywords
This publication has 18 references indexed in Scilit:
- Carnitine metabolism in human subjects I. Normal metabolism,The American Journal of Clinical Nutrition, 1978
- Effects of elevated plasma FFA and insulin on muscle glycogen usage during exerciseJournal of Applied Physiology, 1977
- Dietary Carnitine and Adipose Tissue Turnover Rate in Exercise Trained RatsJournal of Nutrition, 1977
- Carnitine Concentration in Relation to Enzyme Activities and Substrate Utilization in Human Skeletal MusclesScandinavian Journal of Clinical and Laboratory Investigation, 1976
- Significance of Dietary Carnitine for Growth and Carnitine Turnover in RatsJournal of Nutrition, 1974
- Diet, Muscle Glycogen and Physical PerformanceActa Physiologica Scandinavica, 1967
- Muscle Glycogen during Prolonged Severe ExerciseActa Physiologica Scandinavica, 1967
- Metabolic acidosis of exercise in healthy males.Journal of Applied Physiology, 1966
- Action of carnitine on long chain fatty acid oxidation by liverAmerican Journal of Physiology-Legacy Content, 1959
- I1. Zur Methodik der Respiratorischen Quotient‐Bestimmungen in Ruhe und bei Arbeit2Skandinavisches Archiv Für Physiologie, 1939