There is a continuing debate concerning “adjustments” to heart period variability [i.e., heart rate variability (HRV)] for the heart period [i.e., increases inter-beat-intervals (IBI)]. To date, such arguments have not seriously considered the impact a demographic variable, such as gender, can have on the association between HRV and the heart period. A prior meta-analysis showed women to have greater HRV compared to men despite having shorter IBI and higher heart rate (HR). Thus, it is plausible that men and women differ in the association between HRV and HR/IBI. Thus, the present study investigates the potential moderating effect of gender on the association between HRV and indices of cardiac chronotropy, including both HR and IBI. Data from 633 participants (339 women) were available for analysis. Cardiac measures were assessed during a 5-min baseline-resting period. HRV measures included the standard deviation of inter-beat-intervals, root mean square of successive differences, and autoregressive high frequency power. Moderation analyses showed gender significantly moderated the association between all HRV variables and both HR and IBI (each p < 0.05). However, results were not consistent when using recently recommended HRV variables “adjusted” for IBI. Overall, the current investigation provides data illustrating a differential association between HRV and the heart period based on gender. Substantial neurophysiological evidence support the current findings; women show greater sensitivity to acetylcholine compared to men. If women show greater sensitivity to acetylcholine, and acetylcholine increases HRV and the heart period, then the association between HRV and the heart period indeed should be stronger in women compared to men. Taken together, these data suggest that routine “adjustments” to HRV for the heart period are unjustified and problematic at best. As it relates to the application of future HRV research, it is imperative that researchers continue to consider the potential impact of gender.

关于心脏周期变异性[即心率变异性 (HRV)] 的“调整”[即增加心跳间期 (IBI)] 的争论一直存在。迄今为止，这些论点还没有认真考虑人口统计变量（例如性别）对 HRV 和心脏周期之间关联的影响。之前的一项荟萃​​分析显示，尽管 IBI 较短且心率 (HR) 较高，但女性的 HRV 高于男性。因此，男性和女性在 HRV 和 HR/IBI 之间的关联方面存在差异是合理的。因此，本研究调查了性别对 HRV 和心脏变时指数之间关联的潜在调节作用，包括 HR 和 IBI。来自 633 名参与者（339 名女性）的数据可供分析。在 5 分钟的基线休息期间评估心脏测量值。HRV 测量包括节拍间隔的标准偏差、连续差异的均方根和自回归高频功率。调节分析显示性别显着调节了所有 HRV 变量与 HR 和 IBI 之间的关联（每个 p < 0.05)。然而，当使用最近推荐的针对 IBI “调整”的 HRV 变量时，结果并不一致。总体而言，目前的调查提供的数据说明了 HRV 与基于性别的心脏周期之间的差异关联。大量的神经生理学证据支持目前的发现；与男性相比，女性对乙酰胆碱的敏感性更高。如果女性对乙酰胆碱表现出更高的敏感性，并且乙酰胆碱会增加 HRV 和心脏周期，那么与男性相比，女性的 HRV 和心脏周期之间的关联确实应该更强。总之，这些数据表明，对心脏期 HRV 的常规“调整”是不合理的，充其量是有问题的。由于它关系到未来 HRV 研究的应用，