通氣肌疲勞的其一自主變化是呼吸次數增多而深度減少。對於隨意的呼吸運動造成的疲勞呼吸棋式，仍缺乏理解。本研究目的是探求隨意高通氣運動下吸呼棋式的變化。受試者是14名(8男6女)自願的大學生。測量包括肺功 能，最大攝氧量(使用Douglas袋法)，和66%最大意願通氣量的持續高通氣耐力。受試者需要增加呼吸程度，以保持注入目標通氣量的肺量計維持在界定水平下。潮終C02量保持在正常範圍內。過氣量從呼氣一端由壓差氣流器和自設電腦系統測量，並作即時迴饋。持續高通氣耐力時間是55.6±40.0分鐘(平均數士標準差)0 9名受試者( 5男4女)的最後2分鐘呼吸丰多於前(開 始5分鐘達隱定狀況後的2分鐘)呼吸率(46.0±7.8比55.5+6.1次﹒分-1 ，p<.OOl) ，而潮氣量和潮氣量/用力肺活量比例)則減少(分別是2.21+.41比1.80±.27公升， p<.OOl ; 56±7比46±5% ' p<.OOl )。其他5人星相反的變化，分別是58.0±6.2比52.6±7.3次﹒分-1，p<.Ol ; 1.74±.41比1.92+ .51 公升，p<.05 ;以及45±4比49+ 3% ' p<.05。兩模式差別只發生在前數值，而其他測量方面，兩模式沒有顯著差異(p>.05) ，推測與追隨目標而緊張有關。總體而言，力竭的隨意持續高通氣運動，使呼吸變為較快和淺，是通氣肌疲勞的一種適應收縮模式。

One of the autonomic mediated respiratory changes during ventilatory muscles fatigue is a rapid and shallow breathing pattern. The changes of breathing pattern during exhaustive voluntary sustained hyperpneic mancuver is not known. The purpose of this study was to examine such kind of changes. Subjects were 14 (8 males and 6 females) volunteer university students. Measurements included pulmonary functions， maximum oxygen uptake (using Douglas bag technique)， and sustained hyperpnea endurance at 66 % of individual's maximum voluntary ventilation. Subjects were required to increase respiratory effort to maintain the spirometer volume below a defined level. The spirometer was continuously supplied with humidified air at a rate of the target flow. End-tidal CO2 level was maintained within normal range. Ventilation was measured on-line from the expired side using pneumotachograph technique and a custommade computer-assisted system providing an immediate feedback. Sustained hyperpnea time was 55.6±40.0 (Mean±SD). Nine subjects (5 males and 4 females) had higher final respiratory frequency (46.0±7.8 vs. 55.5 ± 6.1 cycle.min-I， p<.OOl)， lower final tidal volume (2.21±.41 vs. 1.80± .27 L， p<.OOl)， and lower final tidal volume/forced vital capacity ratio (56±7 vs. 46 ± 5%， p<.OOl)， The other 5 subjects showed an opposite breathing pattern， respectively， 58.0±6.2 vs. 52.6±7.3 cycle.min-I， p<.Ol; 1.74± .41vs. 1.92±.51L， p<.05;and 45±4 vs.49±3%， p<.05. The difference in breathing pattern between the two groups occurred only in the beginning of hyperpnea， while no difference (p>.05) was found in all other measurements. It was speculated that differ in initial breathing pattern was associated with increased anxiety induced by chasing a moving target. In conclusion， an adaptative response of ventilatory muscle to exhaustive sustained hyperpnea exercise was a faster and less deep breathing pattern.