[Adaptive and maladaptive reactions of the external respiration in the climatic conditions of an arid zone].

Physical performance was assessed in 134 healthy males aged 18-28, residents of the southern Uzbekistan. They were divided into two groups according to the results of bicycle exercise. Group I subjects (32 natives and 38 non-natives) exhibited high physical efficacy, group II subjects--low efficacy (30 and 34 natives and non-natives, respectively). Meteorotropic responses of the external respiration were studied in relation to thermal discomfort, sand storms eve and invasions. Group I subjects, natives in particular, responded by efficient and adequate external respiration, in contrast to group II non-natives who developed pulmonary hyperventilation. The latter is thought a compensatory reaction aimed at maintenance of homeostasis achieved at the expense of inefficient function of the respiratory system.