Journal of Exercise Physiology in Special Populations
Effects of Acute L-carnitine Supplementation with Incremental Training on Fat and Carbohydrate Metabolism in Overweight/Obese and Normal-Weight Young Men
Document Type : Original Article
Authors
1 Secretary of the Sports Nutrition board in the IFMARC (Iran Football Medical Assessment and Rehabilitation Center), Tehran, Iran
2 Department of Physical Education, Shahid Rajaee Teacher Training University, Tehran, Iran
3 Department of Exercise Physiology, Faculty of Sport Sciences, Razi University, Kermanshah, Iran
Abstract
Background: In obesity, individuals experience a decrease in fat oxidation relative to carbohydrates during exercise. The purpose of this study was to evaluate the effects of acute L-carnitine supplementation with incremental treadmill tests on fat and carbohydrate metabolism in overweight and normal-weight young men.
Methods: 24 young men were randomly allocated to two groups: obese (n=12) and normal (n=12). The training protocol and evaluations were performed in two sessions in a double-blind design. Participants ingested 3 grams of L-carnitine or a placebo for 90 minutes before the exercise protocol. For this purpose, the modified Bruce test was used. After 10 days (washout period), the same procedures were repeated, so that the subjects of the supplement group were substituted with the placebo in a cross-over manner. The analysis of fat and carbohydrate metabolism was performed by measuring respiratory gases. An independent t-test was used to compare group differences (p ≤ 0.05).
Results: Acute L-carnitine supplementation with progressive training caused significant improvements in RER (p = 0.005), MFO (p = 0.044), and Carbohydrate Oxidation indices (p = 0.03) in the obese group compared to the normal group. But in Fat max and MFO time indices, despite a slight increase in both groups after supplementation, the two groups were not significantly different from each other.
Conclusion: Acute L-carnitine supplementation at a dose of 3 g 90 minutes before training probably increases fat oxidation more than carbohydrate oxidation in obese young men than normal young men.
Keywords
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