The lateral nasal wall is the movable part of the so-called "nasal valve", the function of which is much discussed, which is subject to many operative steps, but which has never been defined in a physically correct way. It was therefore necessary to study its mobility as a function of the flux and pressure of the respiratory flow. Due to the expected low deflection in low flow areas, a suitable measuring method had to be found for this purpose, which would allow reliable measurements under real conditions. In addition to the comparatively expensive laser distance measurement (micro-epsilon) and optical methods (ToF measurements), the measurement with strain gauges proved to be very accurate, which allowed the creation of elastography as a measurement method in vivo. Unexpectedly, the simultaneous measurement of pressure, flux and deflection on both sides has shown that even in calm breathing, a clear deflection of the nostrils can be measured regularly to varying degrees. As expected, the respiratory mobility of the nostrils depends on the geometric shape of the nostrils as well as on their mechanical condition. A measuring instrument was therefore constructed with which the compressibility of the lateral nasal wall can be measured. First results are demonstrated.