Immediate effects of cervical stimulation and diaphragmatic release on vocal production

Abstract

Introduction: The voice is heavily influenced by breathing and abdominal muscles. Objective: To verify the immediate effects of cervical stimulation and diaphragmatic release on the respiratory and phonatory function of adult women with no vocal complaints. Method: Relaxation maneuvers and eccentric work of the diaphragm were performed together with articulatory maneuver of the third cervical vertebra. Twenty-four women without vocal complaints, aged between 18 and 35 years were part of the intervention. All volunteers were submitted to an evaluation of respiratory muscle strength, maximum phonation time of the vowel /a/, sound pressure level and acoustic vocal analysis, before and after physiotherapeutic intervention. Statistical analysis consisted of the Student's t-test for independent samples and Spearman's correlation. Significance level was set at 5%. Results: There was a significant increase in the maximum phonation time of the vowel /a/ and in the modal sound pressure level. Regarding the acoustic analysis, there was a reduction in the standard deviation values of the fundamental frequency; in the smoothed pitch disturbance quotient; and in the fundamental frequency and amplitude variations. Conclusion: Cervical stimulation and diaphragmatic release improved vocal quality regarding duration of emission, sound pressure, and stability and noise of the glottic signal.