HRVFIT2 study database

The aim of this study was to verify the superiority of high-intensity interval training (HIIT) to enhance parasympathetic activity, cardiorespiratory fitness and cardiac function when compared to moderate intensity continuous training (MICT) in a short and intense cardiac rehabilitation program (RP).
Methods: This is a prospective, monocentric, evaluator-blinded, randomized (1 :1) study with a two arm parallel group design. 31 voluntary chronic heart failure (CHF) patients (LVEF < 45 %) were included either to MICT (n=15) or HIIT group (n=16) for a short RP (27 ± 4 days). They underwent, at entry and at the end of the study, a 24-hour ECG recording, an echocardiography and a cardiopulmonary exercise test. Results: The High-Frequency power (HFnu, %) measured with HRV increased in HIIT group (from 21.2 to 26.4 %, p<0.001) but remained unchanged in MICT group (from 23.1 to 21.9 %, p=0.444) with significant inter-group difference: p=0.003. Resting heart rate (24-h Holter ECG) decreased significantly in both groups (from 68.2 to 64.6 bpm and from 66.0 to 63.5 bpm for MICT and HIIT respectively, without inter-group difference: p=0.578). No difference in premature ventricular contractions was observed between groups. V̇O2peak improvement was greater after HIIT when compared to MICT (+21 % vs +5% respectively, p=0.009). LVEF only improved in HIIT group (from 36.2 to 39.5 %, p=0.034).

本研究旨在验证，在短期高强度心脏康复计划（Rehabilitation Program, RP）中，高强度间歇训练（High-Intensity Interval Training, HIIT）相较于中等强度持续训练（Moderate Intensity Continuous Training, MICT），在提升副交感神经活性、心肺适能与心脏功能方面的优越性。
方法：本研究为前瞻性、单中心、评估者设盲、1:1随机分组的双臂平行对照试验。共纳入31例慢性心力衰竭（Chronic Heart Failure, CHF）患者（左心室射血分数<45%），按1:1比例随机分配至MICT组（n=15）与HIIT组（n=16），接受为期27±4天的短期心脏康复干预。所有受试者均于入组时及研究结束时，接受24小时心电图记录、超声心动图检查及心肺运动试验。
结果：经心率变异性（Heart Rate Variability, HRV）检测得到的高频归一化功率（HFnu, %）在HIIT组中显著升高（从21.2%升至26.4%，p<0.001），而MICT组无明显变化（从23.1%降至21.9%，p=0.444），组间差异具有统计学意义（p=0.003）。两组受试者的静息心率（基于24小时动态心电图Holter ECG）均显著降低：MICT组从68.2次/分钟降至64.6次/分钟，HIIT组从66.0次/分钟降至63.5次/分钟，组间无显著差异（p=0.578）。两组间室性早搏数量无统计学差异。与MICT组相比，HIIT组的峰值摄氧量（Peak Oxygen Uptake, V̇O2peak）提升幅度更为显著（分别提升21%与5%，p=0.009）。左心室射血分数（Left Ventricular Ejection Fraction, LVEF）仅在HIIT组中得到改善（从36.2%升至39.5%，p=0.034）。