In the medical field, many professionals say, “Whispering strains the muscles of the throat and affects vocalization.”
The production of whispering is when the glottis closes (the vocal cord does not vibrate) and a low volume sound is expelled, by means of leaking air through the space between the vocal process and the arytenoid cartilage.
I’ve researched and performed several tests, which determined two informative facts surrounding the mechanics of whispering.
They are as follows: A whispering voice used excessively or improperly can lead to muscle “hypertonia” or “hyposthenia”. Which are medical terms defined as: Too much muscle tone and weakened condition/lack of strength.
Usually whispering needs closing of the vocal cord to occur, ceasing any vibrating, then opens the part closest to the arytenoid cartilage. This action causes strain to the muscles involved.
Furthermore, I’ve found out that the thyroid cartilage is pressed back in many cases.
This is my hypothesis: When the back of the thyroid cartilage moves to the cervical spine, it opens the back of the vocal cord, thus supporting the process of creating a whispering voice.
For instance, when you vocalize with your original voice, if you push your thyroid cartilage to the back, your voice is loosing sound output.
Most people are not aware when they whisper too much or too strained it can cause hypertonic muscles or voice hypertonia.
When measuring muscle mass, I observed hardness. Comparing a standard speaking voice to a whispering voice, the whispering voice’s muscle mass hardened more during vocalizing than the standard speaking voice.
However, a few people had varying results. I noticed the voice quality was different when I listened to their voices carefully. Some pushed their expelled breath out with more force than others, when producing a whisper.
The reason why was because they were making a whispering voice orally, but not through the primary use of the larynx or pharynx.
They controlled the soft tissues very well, which are more elevated than the vocal cords.
I can confidently classify two types of whispering. The first being the one that changed the figure of the back of the tongue and the epipharynx. The second being the one that used the space of the front of the oral cavity, which utilized the tongue, teeth and lips.
I advocate below from those observations.
(1) I think that it does not matter which process is used, in consideration to vocal nodules and polyps, because the purpose is to discourage the movement of the vocal cord when creating a whisper.
However, if you whisper by changing the figure of the back of the tongue and the epipharynx, to consistently vocalize then you are at a higher risk of potentially suffering from hypertonic vocalization – permanently.
(2) I would like to recommend you focus to use the space in the front of your oral cavity for whispering. Which is the tongue, teeth and lips. Especially in cases of aphonia. With aphonia, whispering is used more often. Mainly due to the severely lacking ability, of producing vocalization at standard to high volumes.
A whispering voice when produced improperly or excessively can lead to hypertonic muscles or hypostenic vocalization. In conclusion it is possible to avoid these issues and whisper without causing any strain to the muscles or voice.