Influence of posture, gender and sex on breathing pattern and thoracoabdominal motion during quiet breathing in healthy subjects

Background: The influence of posture and gender on breathing pattern(BP) has been little studied. Literature suggests that aging does not affect BP and thoracoabdominal motion (TM). Aims: To investigate the effects of posture, gender and age on BP and TM during quiet breathing in three postures: sitting, supine and supine with trunk inclination of 45°, in healthy. Methods: 83 subjects(31 men and 52 women), aged 42±22 yrs and normal pulmonary function were studied. Evaluation was performed by optoelectronic plethysmography. Variables analysed: chest wall tidal volume–V CW , respiratory rate-RR and contribution of the pulmonary rib cage–V rcp% , of abdominal rib cage-V rca% and of abdomen–V ab% to tidal volume. Statistical analysis: ANOVA mixed factorial for repeated measures(posture and sex) and multiple linear regression for age was used(p Results: Table 1 shows the comparisons among postures ( Δ: ) and sex. For each year of increase in age, it was observed an average a reduction of 0.20% in V rcp% and 0.08% in V rca% associated with an increase of 0.29% in V ab%. Conclusions: Our results showed that posture, sex and age influence BP and TM.