The voice and air travel

Nowadays, singers/professional vocalists travel all over the world to perform and promote their vocal gifts. I often notice or hear of a deteriorating, tired, tone of voice after a long flight, or road trip. Many singers struggle with maintaining the condition of their voice after long trip, or concert tour.
This issue is most commonly related to swelling.
The swelling occurs when water/moisture is stored or collected in the soft tissues under the skin. This moisture/water build up is caused by a depressed circulatory function. Which is from sitting in the same position for a prolong period of time combined with decreased pressure during air travel.
You generally only notice the swelling of the hands or feet, but actually it swells the vocal cords too. Vocal cord swelling is defined as increased mass and thickness to the vocal cords. As a result,the oscillation rate will get worse and the voice will suffer and become more low-pitched.
The mucosa of the vocal cords is receiving a higher moisture content than the vocal cord muscles. As the mucosa of the vocal cords thickens, it will become more and more difficult to sing high notes.
Even if the person is a highly-skilled professional singer, they will encounter this issue at some point in traveling. If you notice your voice sounds shattered or gravelly, this is because the glottis opens and causes breathing breaks and air leaks. You would need enormous power to overcome this issue, like that of an opera singer!The swelling of the vocal cords is never a good thing for singers to encounter. I have personally labeled this, for reference, ”The Aerial Voice Cord Effect”.
How to prevent from Aerial voice cord swelling during a flight.
First, periodically stretch your body, legs and arms during the flight. This will improve blood flow and is a good way to recover from vocal cord swelling as well. The superior laryngeal artery and vein predominantly affect the vocal cords, and these control the stress and swelling of the thyrohyoid membranes (which is between the hyoid bone and thyroid cartilage) of the larynx.
Those of you who have LDP(larynx Deep Position) will be more prone to suffer from poor blood circulation. The Superior laryngeal artery and veins are being pressed/strained by the narrow space between the hyoid bone and thyroid cartilage. The veins especially have a low inner pressure and will continue to swell due to the reduced circulation of the blood. I advise comforting or stretching the area between the upper thyroid cartilage and hyoid bone using stretching techniques or supportive pads/foam padding: first and middle(Please see the following figure). Practicing this will increase blood circulation, and prevent the issue altogether! Be mindful each individual’s results will vary due to length of flight, altitude and physical conditions.