- 著者
- Kohei TAKEDA Masanao MACHIDA Akiko KOHARA Naomi OMI Tohru TAKEMASA
- 出版者
- Center for Academic Publications Japan
- 雑誌
- Journal of Nutritional Science and Vitaminology (ISSN:03014800)
- 巻号頁・発行日
- vol.57, no.3, pp.246-250, 2011 (Released:2011-09-09)
- 参考文献数
- 21
- 被引用文献数
- 47 78 13
During high-intensity exercise, the concentration of ammonia is augmented in skeletal muscle. Ammonia activates phosphofructokinase and prevents oxidation of pyruvate to acetyl CoA, thus leading to exhaustion. Citrulline is an amino acid component of the urea cycle in the liver, along with ornithine and arginine. The aim of this study was to examine the effect of citrulline supplementation on fatigue and performance during high-intensity exercise. We constructed a swimming exercise protocol, in which mice were subjected to exhaustive swimming with a load of 5% body weight, and measured the time until exhaustion, the blood levels of lactate and ammonia, and the glycogen content of the gastrocnemius and biceps femoris muscles. Citrulline supplementation significantly increased the swimming time until exhaustion. Exercise-induced blood ammonia elevation was repressed by citrulline supplementation, and exercise-induced blood lactate increment in the citrulline-supplemented group was significantly lower than that in the non-supplemented group. Citrulline supplementation may facilitate the detoxification of ammonia via the urea cycle and inhibit additional glycolysis. Our findings suggest that citrulline supplementation may be useful for improving the exercise performance of athletes.
- 著者
- Akiko UCHIZAWA Airi FUNAYAMA Haruka OSUMI Yasushi ENOMOTO Simeng ZHANG Kumpei TOKUYAMA Naomi OMI Hiroyuki SAGAYAMA
- 出版者
- Center for Academic Publications Japan
- 雑誌
- Journal of Nutritional Science and Vitaminology (ISSN:03014800)
- 巻号頁・発行日
- vol.68, no.1, pp.47-54, 2022-02-28 (Released:2022-02-28)
- 参考文献数
- 43
- 被引用文献数
- 3
The food quotient (FQ), which is the rate of macronutrient composition calculated from daily meals, can equal the respiratory quotient over a long term. The FQ is needed to estimate the total energy expenditure (TEE) in doubly labeled water studies. Usually, dietary records (DR) are used for dietary assessment in clinical nutritional studies; however, the DR method’s disadvantage is that it takes time to calculate the results. In comparison, the food frequency questionnaires (FFQ) method is a simple and quick way to calculate results. This study aimed to assess the FQ in Japanese runners, and to compare the two dietary assessment methods, DR and FFQ, to examine whether FFQ is useful in calculating the FQ in healthy young adults and runner. The study consisted of 27 runners and 22 healthy young adults. The participants recorded and took pictures all their meals for 1 wk and provided the FFQ for the same week. The FQ was calculated using the proportions of proteins, fats, carbohydrates, and alcohol. There were no significant differences between the FQs of the runners 0.867 (male: 0.873, female: 0.863) and the healthy young adults 0.871 (male: 0.875, female: 0.867) according to the DR methods. There were no differences in the FQs between DR and FFQ methods for all groups. A significant correlation between the FQs (r=0.502, p<0.01), estimated using the DR, and the FQs estimated using the FFQ was observed. These results suggest that use of the FFQ method can provide comparable data for runners and healthy young adults.