Twenty asthmatic children were asked if they felt their asthmatic attacks to be associated with weather changes. Eleven patients answered that they felt relationship between weather changes and asthmatic attack, (Group A ; 8 severe, 2 moderate, 1 mild asthma). Other nine patients answered they didn't feel any relationship, (Group B ; 2 severe, 7 mild asthma). Most of Group A had severe asthma (73%). In this study, We kept air temperature to be twenty-three degree Celsius and humidity to be fifty percent in the artificial weather chamber.
　Fifteen patients were recruited to exercise challenge (RAMP method). Pulmonary function were evaluated at the sea level and at 1,500 m level (air pressure decresed at 6.7 hPa/min).
　Eleven patients (five of group A, six of group B) experienced the same examination at the sea level and at two meter below sea level (air pressure increased at 22 hPa/min).
　Although FEVI changed 0.92% after fifteen minutes at the sea level in Group A, FEVI fell by 6.46% at 1,500 m level (P = 0.06).
　Three psychological tests, subjective observation record, STAI, and frikker test were also carried out.
　All of the patients got high score both at 1,500 m level and at 2 m below sea level than that at the sea level.
When the air pressure in the artificial weather chamber was increased or decreased, the change in pulmonary function was little if any. They had remarkable psychological anxiety in STAI and frikker test. Since asthmatic children were sensitive to the change of air pressure, they might have physical and/or psychological stress in bad weather.
　Taken together, a change of the air pressure can be thought as one of the triggers, which cause asthmatic attack.

DESCENTE SPORTS SCIENCE Vol.15/THE DESCENTE AND ISHIMOTO MEMORIAL FOUNDATION FOR THE PROMOTION SPORTS SCIENCE