Montalvo-Alonso Juan Jesús, Del Val-Manzano Marta, Ferragut Carmen, Valadés David, López-Samanes Álvaro, Domínguez Raúl, Pérez-López Alberto
Departamento de Ciencias Biomédicas, Área de Educación Física y Deportiva, Facultad de Medicina y Ciencias de La Salud, Universidad de Alcalá, Ctra. Madrid-Barcelona Km 33,600, Alcalá de Henares, 28871, Madrid, Spain.
GICAF Research Group, Research Methods and Evaluation Department, Faculty of Human and Social Sciences, Universidad Pontificia Comillas, Madrid, Spain.
Sci Rep. 2025 May 14;15(1):16781. doi: 10.1038/s41598-025-02021-y.
To examine the single and combined effect of acute beetroot juice and caffeine supplementation in muscular strength, power, and endurance performance. Thirteen resistance-trained males participated in a triple-blind, cross-over, randomized controlled-trial with four conditions: (a) caffeine (CAF); (b) beetroot juice (BJ); (c) caffeine and beetroot juice (CAF + BJ); (d) placebo (PLA). Participants ingested 70 mL of beetroot juice, concentrated NO-rich beverage (BJ, 6.4 mmol NO) or PLA (~ 0.04 mmol NO) 180 min and caffeine or placebo (3 mg/kg) 60 min before the trial. Muscular strength/power was evaluated at 25%, 50%, 75%, 90% and 100%1RM and muscular endurance at 65%1RM, in bench press (BP) and back squat (BS). In all tests, mean (V and W) and peak (V and W) velocity and power output were measured. In BS, muscular strength/power showed a supplement-by-load effect in V and W (P < 0.05, η = 0.167-0.173), with caffeine increased compared to placebo at 75%, 90% and 100%1RM (9-25%, P < 0.005, g = 0.51-1.47); while in muscular endurance, significant differences were found in number of repetitions, V and W (P < 0.05, η > 0.277), in all experimental groups (CAF, BJ and CAF + BJ) compared to placebo (6-17%, P < 0.05, g = 0.46-94). No differences in muscular strength/power or endurance were found in BP. Single and combined acute beetroot juice and caffeine intake increased muscular endurance performance at 65%1RM in back squat but not in bench press exercise.
为研究急性摄入甜菜根汁和咖啡因单独及联合补充对肌肉力量、功率和耐力表现的影响。13名经过抗阻训练的男性参与了一项三盲、交叉、随机对照试验，试验包含四种条件：(a) 咖啡因 (CAF)；(b) 甜菜根汁 (BJ)；(c) 咖啡因和甜菜根汁 (CAF + BJ)；(d) 安慰剂 (PLA)。参与者在试验前180分钟摄入70毫升甜菜根汁、富含一氧化氮的浓缩饮料 (BJ，6.4毫摩尔一氧化氮) 或安慰剂 (约0.04毫摩尔一氧化氮)，并在试验前60分钟摄入咖啡因或安慰剂 (3毫克/千克)。在卧推 (BP) 和后深蹲 (BS) 中，分别于25%、50%、75%、90% 和100% 1RM评估肌肉力量/功率，于65% 1RM评估肌肉耐力。在所有测试中，测量平均 (V和W) 以及峰值 (V和W) 速度和功率输出。在后深蹲中，肌肉力量/功率在V和W方面呈现补充剂与负荷的交互作用 (P < 0.05，η = 0.167 - 0.173)，与安慰剂相比，咖啡因在75%、90% 和100% 1RM时有所增加 (9 - 25%，P < 0.005，g = 0.51 - 1.47)；而在肌肉耐力方面，与安慰剂相比，所有实验组 (CAF、BJ和CAF + BJ) 在重复次数、V和W方面均存在显著差异 (6 - 17%，P < 0.05，g = 0.46 - 0.94)。卧推中未发现肌肉力量/功率或耐力的差异。急性单独及联合摄入甜菜根汁和咖啡因可提高后深蹲65% 1RM时的肌肉耐力表现，但对卧推运动无此效果。
