Effect of different sitting posture on pulmonary function in students

Abstract

The purpose of this study was to investigate changes that occur in pulmonary function when postural changes in the sagittal plane are made in a seated position in students. This cross sectional analytical study was done randomly on 20 boys from Iran, and the results of a forced expiratory manouvre in these young healthy subjects were compared according to body posture. Twenty able-bodied studentsboys (age 13.5±1.09 yr, height 158.25±5.65 cm and weight, 50.45±7.02 kg), participated in this study. Standard spirometric measurements forced vital capacity (FVC), forced expiratory volume in 1 s (FEV1) and peak expiratory flow(PEF) were taken for each subject in each of 3 sitting postures: (normal, slumped and kyphotic) and standing posture. A repeated measure ANOVA and a paired t test indicated that FVC and FEV1 value in standing posture was significantly higher than other sitting postures. In slumped sitting, FVC, FEV1 and PEF significantly decreased from other sitting posture. But there was no significant difference for FVC, PEF and FEV1 between the normal and kyphotic sitting postures. The results showed that FVC, FEV1 and PEF as importance index in health of pulmonary system function, was affected by sitting posture, particularly in slumped sitting posture. Also student should prevent slumped sitting posture. Key words: Pulmonary function, sitting, forced vital capacity, forced expiratory volume in 1 s, peak expiratory flow.