Muscular Patterns and Activation Levels of Auxiliary Breathing Muscles and Thorax Movement in Classical Singing

Abstract

The aim of this paper is to present an overview of the findings in seven studies exploring muscular patterns and muscle activation levels in selected muscles by classical singers. In addition, the relationship of these muscles to thorax (TX) movement was investigated. Loading levels and respiratory phasing of upper trapezius (TR), sternocleidomastoideus (STM) and the scalenes (SC) were investigated in vocalization tasks with variation in vocal loudness and pitch. Further, muscle activity in the posterior neck (PN) was investigated in inhalation and phonation and, finally, TR, intercostal (INT), lateral abdominal (OBL) and anterior abdominal (RC) muscle loading in student and professional singers was examined. Muscle activity was recorded by use of an ambulatory four-channel monitoring system (Physiometer PHY 400, Premed, Norway). TX movement was traced with two strain gauge sensors (RES-117) placed around the upper TX and lower TX. A phasing of upper TR activity to INT and OBL activity was discovered, all muscles supporting the expiration phase. During phonation, TR contributes in the compression of the upper TX, thus serving as an accessory muscle of expiration. TR activity is reduced with short breathing cycles and is mostly inactive in simplified speaking tasks. During phonation, professional opera singers activate the expiratory-phased TR, INT, OBL and RC muscles to higher levels than student singers do. STM and SC show correlated activity patterns during inhalation and phonation by classical singers. During demanding singing, expiratory-phased STM and SC activity peaks produce a counterforce to the compression of upper TX at high pitches. As breathing demands are lowered, STM and SC activity are reduced and attain inspiratory phasing. Substantial muscle activity is observed in PN during inhalation and phonation. EMG biofeedback performed on TR and STM have a secondary effect of lowering EMG activity in PN.

Activity Patterns in Latissimus Dorsi and Sternocleidomastoid in Classical Singers

“…However, all but one of our subjects exhibited activity at vibrato frequency in LD and four of the six in SCM. Although there have recently been a considerable number of electromyograph studies of a range of respiratory muscles during singing (see review by Pettersen 1 ), their activity was described over timescales typical of the gross movements of the thoracic wall and so did not reveal whether patterns of activity at vibrato frequency were present.…”

“…The level of experience of the subjects is obviously one significant factor. For example, professional opera singers tend to show greater activity in a range of respiratory muscles when compared with students, 1 although excessive respiratory muscle activity may also be used to compensate for a lack of proficiency in vocal projection. Gender, age, and voice type may also be significant sources of variability.…”

Future Directions in Surface Electromyography

“…Pettersen and colleagues (e.g., Pettersen, 2005;Pettersen & Westgaard, 2001) have successfully used ambulatory monitoring of SEMG in classical singers. In one study (Pettersen & Westgaard, 2001), trapezius and sternocleidomastoideus muscle activity was recorded bilaterally using an ambulatory monitoring system in two groups of eight conservatory singing students.…”

An application of user-friendly control for a Respiratory Rehabilitation and Assistance Robot

“…Insufficient inhalational and exhalational air volume may cause general health deterioration characterized by lowering of heart rate and metabolic rate, followed by hypotension and hypoxia [4]. In addition, the abdominal muscles are the major muscles used in phonating [5]. For a patients to make loud vocal sounds and to have a sufficiently broad vocal range, enough inhalational air volume is essential [6].…”