Department of Kinesiology, School of Public Health-Bloomington, Indiana University, Bloomington, Indiana, United States.
Indiana University Melvin and Bren Simon Comprehensive Cancer Center, Indianapolis, Indiana, United States.
Am J Physiol Regul Integr Comp Physiol. 2024 Dec 1;327(6):R534-R542. doi: 10.1152/ajpregu.00150.2024. Epub 2024 Sep 9.
To inform end points for future work, we explored the utility of preworkout (i.e., an acute dose before training) beetroot juice (BRJ) combined with exercise (BRJ + EX) to augment indices of physical function in postmenopausal women compared with exercise only (EX). A two-arm pilot study was used to compare 24 postmenopausal women following an 8-wk, circuit-based exercise intervention. Participants were randomized to BRJ + EX ( = 12) or EX ( = 12). BRJ + EX participants consumed 140 mL of BRJ 120-180 min (only) before training for 7 wk, then discontinued during the final week to mitigate carryover effects. Physical function indices were 6-min walk test (6MWT), estimated V̇o, heart rate recovery (HRR), and maximal knee extensor power (P). A treadmill task was used to measure V̇o on-kinetics wherein mean response time (MRT) coincided with the duration to reach 63% of steady-state V̇o. Results showed greater changes (Δ) among BRJ + EX participants for 6MWT distance (40 ± 23 m vs. 8 ± 25 m; = 0.003, = 1.35), ΔV̇o (1.5 ± 0.9 mL·kg·min vs. 0.3 ± 1.0 mL·kg·min; = 0.008, = 1.20), and ΔHRR (-10 ± 6 beats/min vs. -1 ± 9 beats/min; = 0.017, = 1.05). Large and medium effect sizes favoring BRJ + EX were detected for ΔP ( = 0.07, = 0.83) and ΔMRT ( = 0.257, = 0.50), respectively. In postmenopausal women, BRJ + EX appears to magnify some adaptive benefits to physical function including aerobic capacity and recovery beyond that of training without BRJ. Investigation into contributing mechanisms is needed. Though exercise training represents the principal strategy to combat age-related decline, the attendant effects of menopause weaken aspects of exercise adaptation compared with premenopausal women and age-matched men. Here we provide important initial evidence that preworkout (i.e., an acute dose before training) beetroot juice coupled with an 8-wk, circuit-based exercise training intervention may uniquely benefit late postmenopausal women by enhancing indices of physical function including aerobic capacity and recovery.
为了为未来的工作提供信息终点，我们探讨了在绝经后妇女中，与仅运动（EX）相比，运动前（即在训练前摄入一次急性剂量）甜菜根汁（BRJ）与运动相结合（BRJ + EX）对身体功能指数的影响。采用双臂先导研究比较了 8 周基于电路的运动干预后的 24 名绝经后妇女。参与者被随机分配到 BRJ + EX（ = 12）或 EX（ = 12）组。BRJ + EX 组在训练前 120-180 分钟内仅摄入 140 毫升 BRJ，持续 7 周，然后在最后一周停止摄入，以减轻延续效应。身体功能指数为 6 分钟步行测试（6MWT）、估计的 V̇o、心率恢复（HRR）和最大膝关节伸肌力量（P）。跑步机任务用于测量 V̇o 的动力学，其中平均响应时间（MRT）与达到 63%稳态 V̇o 的持续时间一致。结果显示，BRJ + EX 组的 6MWT 距离变化更大（Δ）（40 ± 23 m 与 8 ± 25 m； = 0.003， = 1.35），ΔV̇o（1.5 ± 0.9 mL·kg·min 与 0.3 ± 1.0 mL·kg·min； = 0.008， = 1.20），和 ΔHRR（-10 ± 6 次/分钟与-1 ± 9 次/分钟； = 0.017， = 1.05）。BRJ + EX 对 ΔP（ = 0.07， = 0.83）和 ΔMRT（ = 0.257， = 0.50）的影响较大，有利于 BRJ + EX。在绝经后妇女中，BRJ + EX 似乎可以放大对身体功能的一些适应性益处，包括有氧能力和恢复，而不仅仅是没有 BRJ 的训练。需要进一步研究其作用机制。虽然运动训练是对抗与年龄相关的衰退的主要策略，但与绝经前妇女和年龄匹配的男性相比，绝经的伴随效应会削弱运动适应的某些方面。在这里，我们提供了重要的初步证据，即运动前（即在训练前摄入一次急性剂量）甜菜根汁与 8 周基于电路的运动训练干预相结合，可能通过增强有氧能力和恢复等身体功能指数，为晚期绝经后妇女带来独特的益处。
