Vital capacity (VC), forced expiratory volume in 1 s (FEV(1)), peak expiratory flow (PEF), mean forced expiratory flow (FEV(25-75)), and maximum voluntary volume (MVV) were measured in 36 girls and 36 boys with hearing loss and compared with the same number of normal healthy children, all subjects were aged 10-16 years. They participated in an exercise test to calculate VO(2 max) in order to determine their physical efficiency. We found that all spirometric indices tended to be lower in deaf children, in all age-groups studied and irrespective of gender, compared with their hearing counterparts; the differences assumed significance with respect to PEF and MVV (P<0.05). Moreover, some deaf children had an appreciably lower level of VO(2 max) compared with hearing children. Our results demonstrate that sensory deprivation of deaf children affects functional capabilities of the respiratory system.