Do body mass index and fat volume influence vocal quality, phonatory range, and aerodynamics in females?

Abstract

PURPOSE: To analyze the impact of body weight and body fat volume on selected parameters of vocal quality, phonatory range, and aerodynamics in females. METHODS: Based on measurements of body mass index in combination with body fat volume, 29 normophonic female subjects were classified as normal weight, underweight, and obese. Voice quality was investigated via auditory-perceptual ratings of breathiness, roughness, and overall dysphonia severity, via various acoustic measures and a multiparametric index. Phonatory range performance was examined using selected measures of the voice range profile and speech range profile. Measures of vocally relevant aerodynamics included vital capacity (i.e., VC), expected VC, phonation quotient, and maximum phonation time (i.e., MPT). RESULTS: Significant differences between the three weight groups were found across several measures of intensity, VC, MPT, and shimmer. As compared to the other groups, significantly higher values of maximum and minimum intensity levels, as well as sound pressure level during habitual running speech were observed for the obese group (all p-values<0.05); whereas, the underweight group had significantly lower values for VC and ratio of expected to measured VC (p-values<0.01). Furthermore, underweight subjects differed significantly as compared to normal weight subjects with lower MPT (p=0.025) and higher lowest-F0 (p=0.035). Finally the obese group showed significantly lower shimmer values than the normal weight subjects (p<0.05). CONCLUSION: Body weight and body fat volume appear to influence select objective measures of voice quality, vocal aerodynamics, and phonatory range performance.

Neck Circumference and Vocal Parameters in Women Before and After Bariatric Surgery

“…There was a statistically significant difference in MPT values for the vowels [a], [i], and [u] before and after bariatric surgery (Table 1), which corroborates with the findings of other authors [7][8][9]15] who found a reduction in this parameter in individuals with obesity. This result can be explained by the presence of fat in the neck in obese individuals, which predisposes the increase in type II muscle fibers in the dilator muscles of the upper airways, causing lower respiratory muscle strength [17] and difficulty in mobilizing the airflow to the same degree as in non-obese individuals.…”

“…Acoustic analysis revealed higher fundamental frequency (f0) and reduced maximum phonation time (MPT). Other studies of morbidly obese women have found reduced maximum phonation time [8,9] and low fundamental frequency values by female standards [8].…”

“…Several studies have explained the relationship between body weight, voice production, and the parameters of MPT and f0 [1,8,14,15,9], but research evaluating these parameters before and after bariatric surgery is rare in literature.…”

“…Women with a NC greater than 35 cm exhibit greater body mass [10] and less muscle strength [11], which may explain the lower mean value of MPT before surgery in comparison with the postoperative period following weight loss. The reduction in the diameter of the vocal tract, which decreases the area of the oropharynx [5], contributes to increased supralaryngeal resistance and increased subglottic pressure to overcome such damping, leading to increased resistance of the pharynx [7,8] and a reduction in MPT before surgery, with consequent improvement after weight loss. According to the literature, the reduction of the vocal tract diameter, with a decrease of the oropharyngeal area [5], contributes to the increase in supralaryngeal resistance and increase in subglottic pressure to overcome this damping, which may cause increase in the pharyngeal resistance [8].…”

“…The reduction in the diameter of the vocal tract, which decreases the area of the oropharynx [5], contributes to increased supralaryngeal resistance and increased subglottic pressure to overcome such damping, leading to increased resistance of the pharynx [7,8] and a reduction in MPT before surgery, with consequent improvement after weight loss. According to the literature, the reduction of the vocal tract diameter, with a decrease of the oropharyngeal area [5], contributes to the increase in supralaryngeal resistance and increase in subglottic pressure to overcome this damping, which may cause increase in the pharyngeal resistance [8]. This may have contributed to the reduction of MPT measurements before surgery, with consequent improvement after weight loss.…”