Jiménez-Martínez Pablo, Sánchez-Valdepeñas Juan, Cornejo-Daza Pedro J, Cano-Castillo Clara, Asín-Izquierdo Iván, Alix-Fages Carlos, Pareja-Blanco Fernando, Colado Juan C
Research Group in Prevention and Health in Exercise and Sport (PHES), University of Valencia, Valencia, Spain.
Life Pro Nutrition Research Center, INDIEX, Madrid, Spain.
Front Physiol. 2023 Aug 2;14:1215644. doi: 10.3389/fphys.2023.1215644. eCollection 2023.
This study aimed to examine the effects of phenylcapsaicin (PC) supplementation on strength performance and neuromuscular activity in young trained male subjects. A total of 25 trained subjects [full-squat (SQ) one repetition maximum (1RM) = 125.6 ± 21.0 kg] were enrolled in this randomized, triple-blinded, crossover, placebo-controlled trial. The subjects performed a first session and a post-24 h session for each condition. In the first session, the subjects ingested a high dose of PC (HD, 2.5 mg), a low dose (LD, 0.625 mg), or a placebo (PLA). Their performance in SQ was assessed under a 3% × 8 × 70% 1RM protocol in the first session. Their performances in countermovement jump (CMJ), SQ with 60% 1RM, and isometric squat were measured before and after the SQ protocol in both sessions. The neural activity of the vastus lateralis (VL) and vastus medialis (VM) was recorded via surface electromyography (EMG) and averaged in both sessions. Significant differences between the conditions were reported for lifting velocity, velocity loss, and the 60% load in dynamic SQ ( range = 0.02-0.04). Electrical changes were not identified for any outcome, although neural activity changed across time ( range ≤0.001-0.006). A significant condition × time effect was observed in CMJ compared to PLA ( ≤0.001) and LD ( ≤0.001). Intra-set analyses revealed higher velocities in HD compared to those in LD ( = 0.01) and PLA ( range = 0.004-0.008). Therefore, PC may improve the strength performance and attenuate the mechanical fatigue induced by resistance training in SQ and CMJ exercises.
本研究旨在探讨补充苯基辣椒素（PC）对年轻男性训练者力量表现和神经肌肉活动的影响。本随机、三盲、交叉、安慰剂对照试验共纳入25名训练者[全蹲（SQ）一次重复最大值（1RM）=125.6±21.0千克]。受试者针对每种情况进行了第一节和24小时后的第二节测试。在第一节中，受试者摄入高剂量PC（HD，2.5毫克）、低剂量（LD，0.625毫克）或安慰剂（PLA）。在第一节中，按照3%×8×70% 1RM方案评估他们的深蹲表现。在两节测试中，均在深蹲方案前后测量他们的纵跳（CMJ）、60% 1RM深蹲和等长深蹲表现。通过表面肌电图（EMG）记录股外侧肌（VL）和股内侧肌（VM）的神经活动，并在两节测试中进行平均。报告了不同条件下在起升速度、速度损失和动态深蹲60%负荷方面的显著差异（范围=0.02 - 0.04）。尽管神经活动随时间变化（范围≤0.001 - 0.006），但未发现任何结果有电学变化。与PLA（≤0.001）和LD（≤0.001）相比，在CMJ中观察到显著的条件×时间效应。组内分析显示，与LD（P = 0.01）和PLA（范围=0.004 - 0.008）相比，HD的速度更高。因此，PC可能改善力量表现，并减轻深蹲和纵跳练习中抗阻训练引起的机械疲劳。
