Although the muscular processes of the voice are complex and carry out different functions, the muscles of the voice make up one interconnected system. In fact, a weakness in one set of muscles often results in muscular problems in other areas of the vocal muscular system. Weak vocal fold muscles, for instance, always lead to some degree of pharyngeal closing and inflexibility. The opposite is true also. When all your voice muscles are strong and well coordinated, the natural muscle tension that is created by singing is properly dispensed among the muscle groups of the larynx, pharynx, soft palate, and oral cavity. The result is typically a strong, resonant, and flexible voice, with good quality, control, range, and articulation.
The breakdown of any part of the voice’s muscular system creates other imbalances and results in an overall loss of muscular strength and coordination action between all the actions of phonation. This situation typically leads to the engagement of extraneous muscles during singing. Muscles of the neck and chest, for example, could come into play to try to compensate for the failure of the larynx and pharynx to carry out their workload in a balanced and efficient way. Unfortunately, these fallback maneuvers don't work and contribute to the further weakening of laryngeal, pharyngeal, and soft palate musculature. Vocal disorders like hoarseness, resonance and range reduction, and vocal nodules could also develop as a result.
Vocal nodules are a singer’s greatest fear because they seriously undermine a singer’s power, resonance, and range. They form when there is consistently abrasive contact at particular locations on the outer lips of the vocal folds. Eventually, calluses (nodules) could form at these locations. Nodules inhibit the proper closure of the vocal folds, which reduces resonance production and power. They also undercut the capacity of the vocal folds to stretch to different lengths for pitch and dynamic changes. Although vocal problems, like vocal nodules, often produce no physical sensations, under certain conditions, singing could be physically uncomfortable. In some cases, the muscular constriction could become so advanced that a singer feels strangling-like sensations in the throat during singing—especially when he is struggling to produce high notes. With the extreme participation of extraneous muscles, singing could even become physically exhausting.