Department of Physiology and Pharmacology, Fluminense Federal University, Niterói, Brazil.
Department of Physical Therapy, Universidade Federal de Ciências da Saúde de Porto Alegre, Brazil.
Exp Gerontol. 2021 Jul 15;150:111357. doi: 10.1016/j.exger.2021.111357. Epub 2021 Apr 14.
Inspiratory muscle training improved maximal inspiratory pressure (MIP) and vagal-mediated heart rate variability (HRV) in older women. However, it is unknown what occurs if the training is discontinued (detraining protocol). The aim of this study was to investigate the IMT and detraining effects on resting HRV in older women. Twelve healthy older women (60-72 yrs) enrolled in home-based IMT at 50% MIP (IMT-group) or placebo at 5% MIP (Sham-group) protocol for 4 weeks using a mechanical pressure threshold loading device. The participants were not engaged in any other exercise protocol at that time. During IMT and Sham interventions, the inspiratory load was adjusted weekly by the actual MIP and resting heart rate variability (HRV) evaluated. After training cessation (4 weeks of detraining), participants returned to the lab for HRV and MIP recordings. Adherence to IMT was superior to 95%. IMT increased MIP (23 ± 8 cmHO) and vagal-mediated HRV (normalized HF; 37 ± 8%), following by the reduction of sympatho-vagal balance (LF/HF), from the second week to the end of the protocol compared to sham-group. After detraining, IMT-group reduced MIP (-23 ± 8 cmHO) and vagal-mediated HRV (normalized HF; -38 ± 14%) returning to baseline values. In conclusion, MIP and vagal-HRV improvements induced by IMT were reversed by four weeks of detraining.
吸气肌训练可提高老年女性的最大吸气压力（MIP）和迷走神经介导的心率变异性（HRV）。然而，如果停止训练（脱训方案）会发生什么尚不清楚。本研究旨在探讨吸气肌训练和脱训对老年女性静息心率变异性的影响。12 名健康的老年女性（60-72 岁）参与了一项基于家庭的吸气肌训练，吸气肌训练组在 50%MIP 时使用机械压力阈值加载设备进行 5%MIP（假训练组）的吸气肌训练，为期 4 周。当时，参与者没有参与任何其他运动方案。在吸气肌训练和假训练干预期间，每周根据实际 MIP 和静息心率变异性（HRV）评估调整吸气负荷。在训练停止（脱训 4 周）后，参与者返回实验室进行 HRV 和 MIP 记录。吸气肌训练的依从性优于 95%。与假训练组相比，吸气肌训练增加了 MIP（23±8cmHO）和迷走神经介导的 HRV（归一化 HF；37±8%），并降低了交感神经-迷走神经平衡（LF/HF），从第 2 周持续到方案结束。脱训后，吸气肌训练组的 MIP（-23±8cmHO）和迷走神经介导的 HRV（归一化 HF；-38±14%）下降至基线值。总之，吸气肌训练引起的 MIP 和迷走神经介导的 HRV 改善在四周的脱训后被逆转。
