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Updated: May 28, 2026

Investigation into Deep Breathing through Measurement of Ventilatory Parameters and Observation of Breathing Patterns
Published on: September 16, 2019
Exercise capacity, respiratory mechanics and posture in mouth breathers
Renata Tiemi Okuro1, André Moreno Morcillo, Eulália Sakano
1Campinas State University-Universidade Estadual de Campinas .
Unlabelled:
Chronic and persistent mouth or oral breathing (OB) has been associated with postural changes. Although posture changes in OB causes decreased respiratory muscle strength, reduced chest expansion and impaired pulmonary ventilation with consequences in the exercise capacity, few studies have verified all these assumptions.
Objective:
To evaluate exercise tolerance, respiratory muscle strength and body posture in oral breathing (OB) compared with nasal breathing (NB) children.
Material And Method:
A cross-sectional contemporary cohort study that included OB and NB children aged 8-11 years old. Children with obesity, asthma, chronic respiratory diseases, neurological and orthopedic disorders, and cardiac conditions were excluded. All participants underwent a postural assessment, maximal inspiratory pressure (MIP), maximal expiratory pressure (MEP), the six-minute walk test (6MWT), and otorhinolaryngologic evaluation.
Results:
There were 107 children (45 OB and 62 NB). There was an association between abnormal cervical posture and breathing pattern: 36 (80.0%) OB and 30 (48.4%) NB presented abnormal head posture (OR=4.27 [95% CI: 1.63-11,42], p<0.001). The mean MIP and MEP were lower in OB (p=0.003 and p=0.004).
Conclusion:
OB children had cervical spine postural changes and decreased respiratory muscle strength compared with NB.
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