Sempere-Ruiz Noemí, Sarabia José Manuel, Baladzhaeva Sabina, Moya-Ramón Manuel
Department of Sport Sciences, Sport Research Centre, Miguel Hernandez University, Elche, Spain.
Alicante Institute for Health and Biomedical Research (ISABIAL), Alicante, Spain.
Front Physiol. 2024 Feb 5;15:1329360. doi: 10.3389/fphys.2024.1329360. eCollection 2024.
Exercise intensity distribution is crucial for exercise individualization, prescription, and monitoring. As traditional methods to determine intensity thresholds present limitations, heart rate variability (HRV) using DFA a1 has been proposed as a biomarker for exercise intensity distribution. This index has been associated with ventilatory and lactate thresholds in previous literature. This study aims to assess DFA a1's reliability and validity in determining intensity thresholds during an incremental cycling test in untrained healthy adults. Sixteen volunteers (13 males and 3 females) performed two identical incremental cycling stage tests at least 1 week apart. First and second ventilatory thresholds, lactate thresholds, and HRV thresholds (DFA a1 values of 0.75 and 0.5 for HRVT1 and HRVT2, respectively) were determined in heart rate (HR), relative oxygen uptake (VOrel), and power output (PO) values for both tests. We used intraclass correlation coefficient (ICC), change in mean, and typical error for the reliability analysis, and paired t-tests, correlation coefficients, ICC, and Bland-Altman analysis to assess the agreement between methods. Regarding reliability, HRV thresholds showed the best ICCs when measured in PO (HRVT1: ICC = .87; HRVT2: ICC = .97), comparable to ventilatory and lactate methods. HRVT1 showed the strongest agreement with LA 2.5 in PO ( = 0.09, = .93, ICC = .93, bias = 9.9 ± 21.1), while HRVT2 reported it with VT2 in PO ( = 0.367, = .92, ICC = .92, bias = 5.3 ± 21.9). DFA a1 method using 0.75 and 0.5 values is reliable and valid to determine HRV thresholds in this population, especially in PO values.
运动强度分布对于运动个体化、处方制定和监测至关重要。由于传统的确定强度阈值的方法存在局限性，使用去趋势波动分析（DFA）的α1心率变异性（HRV）已被提议作为运动强度分布的生物标志物。该指标在先前的文献中已与通气阈值和乳酸阈值相关联。本研究旨在评估DFAα1在未经训练的健康成年人进行递增式自行车测试期间确定强度阈值的可靠性和有效性。16名志愿者（13名男性和3名女性）至少间隔1周进行了两次相同的递增式自行车阶段测试。在两次测试的心率（HR）、相对摄氧量（VOrel）和功率输出（PO）值中确定第一和第二通气阈值、乳酸阈值以及HRV阈值（HRVT1和HRVT2的DFAα1值分别为0.75和0.5）。我们使用组内相关系数（ICC）、均值变化和典型误差进行可靠性分析，并使用配对t检验、相关系数、ICC和布兰德-奥特曼分析来评估方法之间的一致性。关于可靠性，当在PO中测量时，HRV阈值显示出最佳的ICC（HRVT1：ICC = 0.87；HRVT2：ICC = 0.97），与通气和乳酸方法相当。HRVT1在PO中与LA 2.5显示出最强的一致性（P = 0.09，r = 0.93，ICC = 0.93，偏差 = 9.9±21.1），而HRVT2在PO中与VT2显示出一致性（P = 0.367，r = 0.92，ICC = 0.92，偏差 =5.3±21.9）。使用0.75和0.5值的DFAα1方法在该人群中确定HRV阈值是可靠且有效的，尤其是在PO值方面。
