Abstract | PURPOSE: Few studies have focused on the metabolic changes induced by creatine supplementation. This study investigated the effects of creatine supplementation on plasma and urinary metabolite changes of athletes after endurance and sprint running. METHODS: Twelve male athletes (20.3 ± 1.4 y) performed two identical (65-70 % maximum heart rate reserved) 60 min running exercises (endurance trial) before and after creatine supplementation (12 g creatine monohydrate/day for 15 days), followed by a 5-day washout period. Subsequently, they performed two identical 100 m sprint running exercises (power trial) before and after 15 days of creatine supplementation in accordance with the supplementary protocol of the endurance trial. Body composition measurements were performed during the entire study. Plasma samples were examined for the concentrations of glucose, lactate, branched-chain amino acids (BCAAs), free- tryptophan (f-TRP), glutamine, alanine, hypoxanthine, and uric acid. Urinary samples were examined for the concentrations of hydroxyproline, 3-methylhistidine, urea nitrogen, and creatinine. RESULTS: CONCLUSIONS: The findings suggest that creatine supplementation tended to decrease muscle glycogen and protein degradation, especially after endurance exercise. However, creatine supplementation might induce collagen proteolysis in athletes after sprint running.
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Authors | Fu-Chun Tang, Chun-Chen Chan, Po-Ling Kuo |
Journal | European journal of nutrition
(Eur J Nutr)
Vol. 53
Issue 1
Pg. 61-71
(Feb 2014)
ISSN: 1436-6215 [Electronic] Germany |
PMID | 23392621
(Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
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Chemical References |
- Amino Acids, Branched-Chain
- Blood Glucose
- Methylhistidines
- Lactic Acid
- Creatinine
- 3-methylhistidine
- Creatine
- Nitrogen
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Topics |
- Adolescent
- Amino Acids, Branched-Chain
(blood)
- Athletes
- Blood Glucose
(metabolism)
- Body Height
- Body Weight
- Creatine
(administration & dosage)
- Creatinine
(urine)
- Dietary Supplements
- Homeostasis
- Humans
- Lactic Acid
(metabolism)
- Male
- Methylhistidines
(urine)
- Nitrogen
(urine)
- Physical Endurance
(drug effects, physiology)
- Running
(physiology)
- Sports Nutritional Physiological Phenomena
- Young Adult
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