Montalvo-Alonso Juan Jesús, Del Val-Manzano Marta, Cerezo-Telléz Ester, Ferragut Carmen, Valadés David, Rodríguez-Falces Javier, 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, 28871, Alcalá de Henares, Madrid, Spain.
Neuromusculoskeletal Physical Therapy in Stages of Life Research Group (FINEMEV), Department of Nursing and Physical Therapy, Faculty of Medicine and Health Sciences, Universidad de Alcalá, Autovía A2, km 33.200, 28805, Alcalá de Henares, Madrid, Spain.
Eur J Appl Physiol. 2025 Jun 6. doi: 10.1007/s00421-025-05820-3.
This study examined the effects of acute caffeine intake on muscular electrical activity during strength, power, and endurance performance tests at different times of day in bench press and back squat exercises.
Thirteen resistance-trained men participated in a triple-blind, cross-over, randomized controlled trial with four conditions: (a) morning with caffeine, (b) morning with placebo, (c) evening with caffeine, and (d) evening with placebo. Trials were conducted at 9:00 AM and 6:00 PM, with participants consuming caffeine or placebo (3 mg/kg) 60 min prior. Muscular strength/power was tested at 25%, 50%, 75%, and 90% one-repetition maximum (1RM) for bench press and back squat, while muscular endurance was assessed at 65% 1RM through a set-to-failure. Surface electromyography (EMG) measured muscle electrical activity.
In muscular strength/power tests, caffeine increased mean velocity (V) and power output (W) in the back squat at 75% (P = 0.012-0.001, g = 3.84-2.71) and 90%1RM (P = 0.043-0.009, g = 2.77-2.46) in both morning and evening trials. At 25%1RM, caffeine counteracts morning performance decline in bench press (10-11%, P = 0.001, g = 2.62-1.68) and back squat (8-11%, P = 0.010-0.003, g = 2.22-1.64). In muscular endurance tests, caffeine increased V and W in bench press in the morning (11-12%, P = 0.003-0.005, g = 2.55-1.89) and back squat in both morning and evening trials (6-9%, P = 0.001-0.027, g = 2.79-1.73). EMG activity remained unchanged in all conditions.
Acute caffeine intake enhances muscular strength/power at moderate-to-high loads (75%- 90%1RM) and endurance performance (65%1RM) in the back squat while counteracting morning declines at light-load (25%1RM) for both exercises without altering muscle electrical activity.
本研究考察了在一天中的不同时间进行卧推和深蹲练习的力量、功率及耐力性能测试期间，急性摄入咖啡因对肌肉电活动的影响。
13名有阻力训练经验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）上午摄入咖啡因，（b）上午摄入安慰剂，（c）晚上摄入咖啡因，（d）晚上摄入安慰剂。试验分别在上午9:00和下午6:00进行，参与者在试验前60分钟摄入咖啡因或安慰剂（3毫克/千克）。卧推和深蹲的肌肉力量/功率测试在1次重复最大值（1RM）的25%、50%、75%和90%负荷下进行，而肌肉耐力则通过在65% 1RM负荷下进行一组至力竭来评估。表面肌电图（EMG）用于测量肌肉电活动。
在肌肉力量/功率测试中，咖啡因在上午和晚上的试验中均使深蹲在75%（P = 0.012 - 0.001，g = 3.84 - 2.71）和90% 1RM（P = 0.043 - 0.009，g = 2.77 - 2.46）负荷下的平均速度（V）和功率输出（W）增加。在25% 1RM负荷下，咖啡因可抵消上午卧推（10 - 11%，P = 0.001，g = 2.62 - 1.68）和深蹲（8 - 11%，P = 0.010 - 0.003，g = 2.22 - 1.64）性能的下降。在肌肉耐力测试中，咖啡因使上午卧推的V和W增加（11 - 12%，P = 0.003 - 0.005，g = 2.55 - 1.89），并使上午和晚上试验中的深蹲V和W增加（6 - 9%，P = 0.001 - 0.027，g = 2.79 - 1.73）。在所有条件下，EMG活动均保持不变。
急性摄入咖啡因可增强深蹲在中高负荷（75% - 90% 1RM）下的肌肉力量/功率以及耐力性能（65% 1RM），同时抵消两种练习在轻负荷（25% 1RM）下上午的性能下降，且不改变肌肉电活动。
