Ainsworth D M, Smith C A, Eicker S W, Ducharme N G, Henderson K S, Snedden K, Dempsey J A
Department of Clinical Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY 14850, USA.
Respir Physiol. 1997 Nov;110(2-3):287-94. doi: 10.1016/s0034-5687(97)00094-7.
In exercising quadrupeds, limb movement is often coupled with breathing frequency. This finding has lead some investigators to conclude that locomotory forces, associated with foot plant, abdominal visceral displacements or lumbo-sacral flexion, are the primary determinants of airflow generation. Analysis of respiratory muscle electrical activation (EMG) and contraction profiles in chronically instrumented dogs and horses, along with measurements of esophageal pressure (Pes) changes and limb movements, provide evidence that each breath during the exercise hyperpnea is determined by respiratory neuromuscular events. Specifically: (1) Phasic diaphragmatic EMG and tidal shortening are always synchronous with decreases in Pes; (2) decrements in Pes are always associated with inspiratory flow generation; and (3) strict phase coupling between breathing and stride frequency is not obligatory. Thus, although locomotory-associated forces may minimally assist with flow generation, they are not the primary determinants of breathing during exercise.
在运动的四足动物中，肢体运动常常与呼吸频率相关联。这一发现使得一些研究人员得出结论，认为与足部着地、腹部内脏移位或腰骶部屈曲相关的运动力是气流产生的主要决定因素。对长期植入仪器的狗和马的呼吸肌电活动（EMG）和收缩情况进行分析，同时测量食管压力（Pes）变化和肢体运动，结果表明运动性深呼吸期间的每一次呼吸都是由呼吸神经肌肉事件决定的。具体而言：（1）膈肌的阶段性EMG和潮气量缩短总是与Pes的降低同步；（2）Pes的降低总是与吸气气流的产生相关；（3）呼吸与步频之间严格的相位耦合并非必需。因此，尽管与运动相关的力可能对气流产生有极小的辅助作用，但它们并非运动期间呼吸的主要决定因素。
