Russell Matthew E B, Scott April B, Boggero Ian A, Carlson Charles R
Psychology Department, University of Kentucky, Lexington, Kentucky, USA.
College of Dentistry, Division of Orofacial Pain, University of Kentucky, Lexington, Kentucky, USA.
Psychophysiology. 2017 Mar;54(3):358-365. doi: 10.1111/psyp.12791. Epub 2016 Dec 7.
Heart rate variability (HRV) is associated with positive physiological and psychological effects. HRV is affected by breathing parameters, yet debate remains regarding the best breathing interventions for strengthening HRV. The objective of the current study was to test whether the inclusion of a postexhalation rest period was effective at increasing HRV, while controlling for breathing rate. A within-subject crossover design was used with 40 participants who were assigned randomly to a breathing pattern including a postexhalation rest period or a breathing pattern that omitted the postexhalation rest period. Participants completed training on each breathing pattern, practiced for 6 min, and sat quietly during a 5-min washout period between practices. Participants were given instructions for diaphragmatic breathing at a pace of six breaths/minute with or without a postexhalation rest period. Recordings of heart rate, breathing rate, HF-HRV, RMSSD, LF-HRV, and SDNN were collected before and during each of the breathing trials. HRV indices were derived from Lead 1 ECG recordings. Pairwise contrasts showed that inclusion of a postexhalation rest period significantly decreased heart rate (p < .001) and increased HF-HRV (p < .05). No differences were found for breathing rates (p > .05), RMSSD (p > .05), and SDNN (p > .05). Results indicated that omission of the postexhalation rest period resulted in higher LF-HRV (p < .05). A postexhalation rest period improves HF-HRV, commonly associated with self-regulatory control, yet the importance of a postexhalation rest period requires further exploration.
心率变异性（HRV）与积极的生理和心理效应相关。HRV受呼吸参数影响，但关于增强HRV的最佳呼吸干预措施仍存在争议。本研究的目的是测试在控制呼吸频率的同时，呼气后休息期的纳入是否能有效增加HRV。采用受试者内交叉设计，40名参与者被随机分配到包含呼气后休息期的呼吸模式或省略呼气后休息期的呼吸模式。参与者完成了每种呼吸模式的训练，练习6分钟，并在两次练习之间的5分钟洗脱期安静坐着。指导参与者以每分钟6次呼吸的频率进行膈肌呼吸，有或没有呼气后休息期。在每次呼吸试验之前和期间收集心率、呼吸频率、高频心率变异性（HF-HRV）、连续差值均方根（RMSSD）、低频心率变异性（LF-HRV）和全部窦性心搏间期标准差（SDNN）的记录。HRV指标来自I导联心电图记录。成对对比显示，纳入呼气后休息期显著降低了心率（p < 0.001）并增加了HF-HRV（p < 0.05）。呼吸频率（p > 0.05）、RMSSD（p > 0.05）和SDNN（p > 0.05）未发现差异。结果表明，省略呼气后休息期导致更高的LF-HRV（p < 0.05）。呼气后休息期改善了通常与自我调节控制相关的HF-HRV，但呼气后休息期的重要性需要进一步探索。
