Perry Sean, Khovanova Natasha, Khovanov Igor
Annu Int Conf IEEE Eng Med Biol Soc. 2020 Jul;2020:461-464. doi: 10.1109/EMBC44109.2020.9175778.
During running, interactions were considered between three physiological oscillators - the heart, breaths, and steps. During intense exercise, the oscillations of all three systems are close to regular, producing good conditions to observe and characterise synchronization. The origin, as well as any physiological significance, of synchronization between these systems during running is not fully accepted or understood. Furthermore, the impact on synchronization of controlling both breathing and step rate has not been previously reported in detail. This study aims to measure cardiolocomotor, cardiorespiratory and respiratory- locomotor synchronization during different running protocols. Breathing was controlled by taking a fixed number of steps per breath (ratios of 5:1 and 3:1). Step rate was then guided at rates close to active heart rate, to instigate 1:1 phase-locking. Instantaneous phase difference quantified synchronization episodes. We have successfully observed all three forms of synchronization during all running protocols. Furthermore, coupling between heartbeats and steps was more pronounced when step rate was guided, and both cardiorespiratory and respiratory-locomotor coupling were extended when breathing rate was fixed to steps. These are exciting initial results from a novel experimental design, highlighting the complex interconnection that exists between these three systems during running, and the conditions to best observe the phenomena.
在跑步过程中，研究了心脏、呼吸和步伐这三个生理振荡器之间的相互作用。在剧烈运动期间，这三个系统的振荡都接近规则状态，为观察和描述同步性创造了良好条件。跑步过程中这些系统之间同步的起源以及任何生理意义尚未得到充分认可或理解。此外，之前尚未详细报道过控制呼吸频率和步频对同步性的影响。本研究旨在测量不同跑步方案中的心肺运动同步、心肺同步和呼吸运动同步。通过控制每呼吸固定步数（5:1和3:1的比例）来控制呼吸。然后将步频引导至接近主动心率的水平，以促成1:1锁相。瞬时相位差量化了同步事件。我们在所有跑步方案中均成功观察到了这三种同步形式。此外，当步频受到引导时，心跳与步伐之间的耦合更为明显，而当呼吸频率与步伐固定时，心肺耦合和呼吸运动耦合均得到增强。这些是来自新颖实验设计的令人兴奋的初步结果，突出了跑步过程中这三个系统之间存在的复杂相互联系，以及最佳观察该现象的条件。
