The current diagnostic procedures for assessing physiological response to exercise comprise blood lactates measurements, ergospirometry, and electrocardiography. The first is not continuous, the second requires specialized equipment distorting natural breathing, and the last is indirect. Therefore, we decided to perform the feasibility study with impedance pneumography as an alternative technique. We attempted to determine points in respiratory-related signals, acquired during stress test conditions, that suggest a transition similar to the gas exchange threshold. In addition, we analyzed whether or not respiratory activity reaches steady states during graded exercise. Forty-four students (35 females), practicing sports on different levels, performed a graded exercise test until exhaustion on cycloergometer. Eventually, the results from 34 of them were used. The data were acquired with Pneumonitor 2. The signals demonstrated that the steady state phenomenon is not as evident as for heart rate. The results indicated respiratory rate approaches show the transition point at the earliest (more than 6 min before the end of the exercise test on average), and the tidal volume ones at the latest (less than 5 min). A combination gave intermediate findings. The results showed the impedance pneumography appears reasonable for the transition point estimation, but this should be further studied with the reference.

中文翻译：

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利用阻抗呼吸描记法估计过渡点的可行性研究

当前用于评估对运动的生理反应的诊断程序包括血乳酸测量、人体肺活量测定法和心电图。第一个不是连续的，第二个需要扭曲自然呼吸的特殊设备，最后一个是间接的。因此，我们决定使用阻抗呼吸描记术作为替代技术进行可行性研究。我们试图确定在压力测试条件下获得的呼吸相关信号中的点，这些点表明类似于气体交换阈值的转变。此外，我们分析了分级运动期间呼吸活动是否达到稳定状态。44 名学生（35 名女性）进行了不同级别的运动，在循环测力计上进行了分级运动测试，直到筋疲力尽。最终，使用了其中 34 个的结果。数据是用 Pneumonitor 2 采集的。信号表明稳态现象不像心率那样明显。结果表明，呼吸频率法最早显示过渡点（平均在运动试验结束前6分钟以上），最晚（小于5分钟）显示潮气量。组合给出了中间结果。结果表明，阻抗呼吸描记法对于转变点的估计似乎是合理的，但这应该与参考资料进一步研究。结果表明，呼吸频率法最早显示过渡点（平均在运动试验结束前6分钟以上），最晚（小于5分钟）显示潮气量。组合给出了中间结果。结果表明，阻抗呼吸描记法对于转变点的估计似乎是合理的，但这应该与参考资料进一步研究。结果表明，呼吸频率法最早显示过渡点（平均在运动试验结束前6分钟以上），最晚（小于5分钟）显示潮气量。组合给出了中间结果。结果表明，阻抗呼吸描记法对于转变点的估计似乎是合理的，但这应该与参考资料进一步研究。