Department of Nutrition and Movement Sciences, School of Nutrition and Translational Research in Metabolism (NUTRIM), Faculty of Health, Medicine and Life Sciences, Maastricht University, Universiteitssingel 50, 6229 ER, Maastricht, The Netherlands.
Department of Surgery, School of Nutrition and Translational Research in Metabolism (NUTRIM), Faculty of Health, Medicine and Life Sciences, Maastricht University, Maastricht, The Netherlands.
Appl Psychophysiol Biofeedback. 2023 Dec;48(4):453-460. doi: 10.1007/s10484-023-09599-x. Epub 2023 Jul 29.
The short-term scaling exponent of detrended fluctuation analysis (DFA-a1) of heart rate variability may be a helpful tool to assess autonomic balance as a prelude to daily, individualized training. For this concept to be useful, between-session reliability should be acceptable. The aim of this study was to explore the reliability of DFA-a1 during a low-intensity exercise session in both a non-fatigued and a fatigued condition in healthy males and females. Ten participants completed two sessions with each containing an exhaustive treadmill ramp protocol. Before and after the fatiguing ramp, a standardized submaximal low-intensity exercise bout was performed during which DFA-a1, heart rate, and oxygen consumption (VO) were measured. We compared between-session reliability of all metrics prior to the ramps (i.e., non-fatigued status) and after the first ramp (i.e., fatigued status). Intraclass correlation coefficients (ICC) with 95% confidence intervals (CI), the standard error of measurement, and the smallest worthwhile change (SWC) were determined. The ICC and SWC pre fatiguing ramp were 0.85 (95% CI 0.39-0.96) and 5.5% for DFA-a1, 0.85 (0.38-0.96) and 2.2% for heart rate, and 0.84 (0.31-0.96) and 3.1% for VO. Post fatiguing ramp, the ICC and SWC were 0.55 (0.00-0.89) and 7.9% for DFA-a1, 0.91 (0.62-0.98) and 1.6% for heart rate, and 0.80 (0.17-0.95) and 3.0% for VO. DFA-a1 shows generally acceptable to good between-session reliability with a SWC of 0.06 and 0.07 (5.5-7.9%) during non-fatigued and fatigued conditions. This suggests that this metric may be useful to inform on training readiness.
心率变异性去趋势波动分析（DFA-a1）的短期标度指数可能是评估自主平衡的有用工具，可以作为日常个体化训练的前奏。为了使这一概念具有实用性，其组间信度应该是可以接受的。本研究的目的是在健康男性和女性中，探索非疲劳和疲劳状态下，低强度运动过程中 DFA-a1 的组间可靠性。10 名参与者完成了两次试验，每次试验都包含一个耗竭式跑步机斜坡方案。在疲劳斜坡前后，进行了标准化的亚最大强度低强度运动试验，在此期间测量了 DFA-a1、心率和耗氧量（VO）。我们比较了斜坡前（即非疲劳状态）和第一次斜坡后（即疲劳状态）所有指标的组间可靠性。使用 95%置信区间（CI）、测量标准误差和最小有意义变化（SWC）确定了组内相关系数（ICC）。DFA-a1、心率和 VO 的疲劳前 ICC 和 SWC 分别为 0.85（95%CI 0.39-0.96）和 5.5%、0.85（0.38-0.96）和 2.2%以及 0.84（0.31-0.96）和 3.1%。疲劳后，DFA-a1、心率和 VO 的 ICC 和 SWC 分别为 0.55（0.00-0.89）和 7.9%、0.91（0.62-0.98）和 1.6%以及 0.80（0.17-0.95）和 3.0%。DFA-a1 显示出在非疲劳和疲劳状态下具有良好到一般的组间可靠性，SWC 分别为 0.06 和 0.07（5.5-7.9%）。这表明该指标可能有助于告知训练准备情况。
