Kim Mijin, Isoda Hiroko, Okura Tomohiro
R&D Center for Tailor-Made QOL, University of Tsukuba, Tsukuba 305-8550, Japan.
Alliance for Research on the Mediterranean and North Africa, University of Tsukuba, Tsukuba 305-8572, Japan.
Foods. 2021 Dec 15;10(12):3117. doi: 10.3390/foods10123117.
The combined intake of citrulline (CIT) and leucine (LEU) can stimulate protein synthesis. Therefore, this study aimed to investigate the effect of combined intake of CIT and LEU accompanied by exercise for 20 weeks on body composition, physical activity (PA), and amino acid concentrations in older Japanese women with low body mass index (BMI) (16 to 21 kg/m) using a randomized, double-blind, placebo-controlled design. The supplement was administered twice a day for 20 weeks (Ex (exercise) + CIT·LEU group, = 10: mainly 0.8 g CIT and 1.6 g LEU; Ex + Placebo group, = 13: mainly 3.5 g carbohydrate). Additionally, both groups exercised (weight-bearing exercise, square stepping exercise) once a week for 75 min. Body composition, PA, and amino acid concentrations in the plasma were measured. Body weight, BMI, body mass, household PA, total PA, and phenylalanine significantly increased in the Ex + CIT·LEU group ( < 0.05) post intervention. This study suggests that the combined intake of CIT and LEU accompanied by exercise can improve body weight, BMI, body mass, and PA in older women with low BMI, which may prevent sarcopenia and frailty.
瓜氨酸（CIT）和亮氨酸（LEU）联合摄入可刺激蛋白质合成。因此，本研究旨在采用随机、双盲、安慰剂对照设计，调查20周内联合摄入CIT和LEU并进行运动对低体重指数（BMI，16至21kg/m²）的日本老年女性身体成分、身体活动（PA）和氨基酸浓度的影响。补充剂每天服用两次，持续20周（运动+CIT·LEU组，n = 10：主要为0.8g CIT和1.6g LEU；运动+安慰剂组，n = 13：主要为3.5g碳水化合物）。此外，两组每周进行一次运动（负重运动、方形踏步运动），持续75分钟。测量身体成分、PA和血浆中的氨基酸浓度。干预后，运动+CIT·LEU组的体重、BMI、体重、家庭PA、总PA和苯丙氨酸显著增加（P<0.05）。本研究表明，联合摄入CIT和LEU并进行运动可改善低BMI老年女性的体重、BMI、体重和PA，这可能预防肌肉减少症和虚弱。
