Hark William T, Thompson William M, McLaughlin Timothy E, Wheatley Lisa M, Platts-Mills Thomas A E
Asthma and Allergic Diseases Center, University of Virginia, Charlottesville, Virginia 22908, USA.
Ann Allergy Asthma Immunol. 2005 Feb;94(2):247-50. doi: 10.1016/S1081-1206(10)61303-8.
Spontaneous sighs are thought to play an important role in preventing atelectasis and in regulating airway tone. Recent studies have provided a mechanism by which expansion of the lungs could cause relaxation of smooth muscle.
To investigate breathing patterns during 2 forms of sedentary behavior: reading and watching television.
Breathing patterns were monitored for 1 to 2 hours to document respiratory rates and sigh rates. Each participant was monitored while reading and while watching a movie on videotape. During the first experiment (17 controls), metabolic rates were also measured. In the second experiment (18 controls and 9 patients with mild-to-moderate asthma), only breathing patterns were monitored.
There were no significant differences in respiratory or metabolic rates between the 2 activities. In contrast, in the first experiment, 13 of 17 controls had lower sigh rates while watching a videotape than while reading (P < .01). In the second experiment, the sigh rate was significantly lower overall while watching a videotape (mean, 13.7 sighs per hour; range, 1.8-26.0 sighs per hour) than while reading (mean, 19.3 sighs per hour; range, 7.7-30.0 sighs per hour) (P < .001). A similar decrease was observed in patients with asthma (P < .01).
Given that many children and adults watch television for 5 or more hours per day, breathing patterns during this time may be relevant to lung function. Our results demonstrate that prolonged periods of watching a videotape are associated with lower sigh rates than while reading. Further research is needed to determine whether these changes are relevant to increased bronchial reactivity.
自主叹息被认为在预防肺不张和调节气道张力方面发挥着重要作用。最近的研究提供了一种机制，通过该机制肺的扩张可导致平滑肌松弛。
研究两种久坐行为（阅读和看电视）期间的呼吸模式。
监测呼吸模式1至2小时，以记录呼吸频率和叹息频率。每位参与者在阅读和观看录像带电影时都受到监测。在第一个实验（17名对照者）中，还测量了代谢率。在第二个实验（18名对照者和9名轻度至中度哮喘患者）中，仅监测呼吸模式。
这两种活动之间的呼吸或代谢率没有显著差异。相比之下，在第一个实验中，17名对照者中有13名在观看录像带时的叹息频率低于阅读时（P <.01）。在第二个实验中，总体而言，观看录像带时的叹息频率（平均每小时13.7次叹息；范围为每小时1.8 - 26.0次叹息）显著低于阅读时（平均每小时19.3次叹息；范围为每小时7.7 - 30.0次叹息）（P <.001）。哮喘患者也观察到类似的下降（P <.01）。
鉴于许多儿童和成人每天看电视5小时或更长时间，这段时间的呼吸模式可能与肺功能相关。我们的结果表明，长时间观看录像带与比阅读时更低的叹息频率相关。需要进一步研究以确定这些变化是否与支气管反应性增加有关。
