Tsuchiya Yosuke, Ueda Hisashi, Shimizu Takashi, Yokoi Kaori, Yanagimoto Kenichi, Ochi Eisuke
Center for Liberal Arts, Laboratory of Health and Sports Sciences, Meiji Gakuin University, Kanagawa, Japan.
Faculty of Health Care and Medical Sports, Teikyo Heisei University, Chiba, Japan.
J Am Nutr Assoc. 2025 Mar-Apr;44(3):190-197. doi: 10.1080/27697061.2024.2413363. Epub 2024 Oct 14.
Structured lipids containing medium-chain fatty acids, eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA) from fish oil (EPA/MCT) and it improve overall endurance. However, their effects on local muscle endurance remain unclear. This study aimed to investigate the effects of EPA/MCT intake on muscle endurance during leg extension exercises and subsequent muscle fatigue.
This 8-week, placebo-controlled, randomized, double-blind parallel-group trial involved 20 healthy young men. Subjects were randomly assigned to an EPA/MCT group (10 subjects) and a placebo group (PL group, 10 subjects). They consumed 4560 mg of the test food daily for 8 wk before an exercise intervention. The EPA/MCT supplement contained 600 mg of EPA, 260 mg of DHA, and 1890 mg of MCT (1110 mg of octanoic acid and 780 mg of decanoic acid). After the 8-week intervention, the subjects performed four sets of leg extension exercises at 40% of their body weight until exhaustion. The number of repetitions per set and the total repetitions across the four sets served as indicators of muscle endurance. Isometric maximum voluntary contraction (MVC), range of motion, circumference, muscle thickness, echo intensity, and muscle stiffness were measured before and after exercise to assess muscle fatigue.
There was no difference between the groups in the number of repetitions for sets 1-4 or in the total number of repetitions during the leg extension exercise. In the EPA/MCT group, a significant negative correlation was observed between the increase in the blood EPA/AA ratio and the rate of decrease in the number of repetitions. Additionally, the decrease in MVC after exercise was significantly smaller in the EPA/MCT group than in the PL group.
Our study results suggest that an 8-week intake of EPA/MCT can increase the blood EPA/AA ratio and improve muscle endurance performance. Additionally, EPA/MCT intake reduces muscle fatigue after exercise.
含有中链脂肪酸、二十碳五烯酸（EPA）和鱼油中二十二碳六烯酸（DHA）的结构化脂质（EPA/MCT）可提高整体耐力。然而，它们对局部肌肉耐力的影响尚不清楚。本研究旨在探讨摄入EPA/MCT对腿部伸展运动期间肌肉耐力及随后肌肉疲劳的影响。
这项为期8周的安慰剂对照、随机、双盲平行组试验纳入了20名健康年轻男性。受试者被随机分为EPA/MCT组（10名受试者）和安慰剂组（PL组，10名受试者）。在进行运动干预前，他们每天食用4560毫克的测试食物，持续8周。EPA/MCT补充剂含有600毫克EPA、260毫克DHA和1890毫克MCT（1110毫克辛酸和780毫克癸酸）。8周干预后，受试者以其体重的40%进行四组腿部伸展运动，直至力竭。每组的重复次数和四组的总重复次数作为肌肉耐力指标。在运动前后测量等长最大自主收缩（MVC）、活动范围、周长、肌肉厚度、回声强度和肌肉僵硬度，以评估肌肉疲劳。
两组在第1 - 4组的重复次数或腿部伸展运动期间的总重复次数上没有差异。在EPA/MCT组中，血液中EPA/AA比值的增加与重复次数减少率之间存在显著负相关。此外，EPA/MCT组运动后MVC的下降明显小于PL组。
我们的研究结果表明，摄入8周的EPA/MCT可提高血液中EPA/AA比值并改善肌肉耐力表现。此外，摄入EPA/MCT可减轻运动后的肌肉疲劳。
