Laboratory of Respiration Physiology, Pavlov Institute of Physiology, Russian Academy of Science, Saint-Petersburg, Russia.
J Physiol Pharmacol. 2009 Nov;60 Suppl 5:111-5.
The aim of the present study was to determine the development of the inspiratory muscle fatigue in healthy human during incremental cycling to exhaustion under mild and heavy resistive loaded breathing in air and oxygen. Minute ventilation, tidal volume, respiratory rate, inspiratory mouth pressure, and parasternal EMG activities were recorded during an incremental cycling test under mild (12 cmH(2)O x l(-1) x s(-1)) and heavy (40 cmH(2)O x l(-1) x s(-1)) resistive loading in air and oxygen in 8 men. The degree of inspiratory muscle fatigue was evaluated by analysis of the dynamics of inspiratory mouth pressure, 'tension-time' index, and the fall of the high-to-low (H/L) ratio of the parasternal EMG. It was found that oxygen breathing slowed the development of inspiratory muscles fatigue evoked by incremental cycling only during mild resistive loading, whereas hyperoxia had not influence on inspiratory muscle endurance during heavy resistive loading.
本研究旨在确定在空气和氧气中进行递增性踏车至力竭运动时，健康人在轻度和重度呼吸阻力负荷下吸气肌疲劳的发展情况。8 名男性在空气和氧气中进行轻度（12cmH(2)O x l(-1) x s(-1)）和重度（40cmH(2)O x l(-1) x s(-1)）呼吸阻力负荷递增性踏车试验时，记录分钟通气量、潮气量、呼吸频率、口腔吸气压力和胸锁乳突肌肌电图活动。通过分析口腔吸气压力的动力学、张力时间指数和胸锁乳突肌肌电图高到低（H/L）比值的下降来评估吸气肌疲劳的程度。结果发现，氧气呼吸仅在轻度呼吸阻力负荷下减缓了递增性踏车引起的吸气肌疲劳的发展，而高氧对重度呼吸阻力负荷下的吸气肌耐力没有影响。
