Biomaterial Database

Effects of dry and humid climates on exercise-induced asthma in children and preadolescents. 1977

O Bar-Or, and I Neuman, and R Dotan

Among factors which possibly influence the responses of asthmatic children to exercise, climate has received little attention. This study was performed to determine whether the level of air humidity is a factor to be considered. Twenty asthmatic (extrinsic perennial) girls and boys, 6 to 14 yr of age, with unverified history of exercise-induced asthma (EIA) took part. They rested and exercised in a climatic chamber in dry (25% relative humidity) and humid (90%) sessions at 25 degrees to 26 degrees C. One to three weeks separated the sessions, the order of which was counterbalanced. No changes in pulmonary functions (FVC, FEV 1.0, MMEF, MBC) were found following a sitting period of 60 min in either climate. Five and ten minutes following the treadmill run, however, bronchoconstriction was distinctly more pronounced in the dry than in the humid climate. Exercise heart rate and the subjective rating of effort were not affected by climate. It was concluded that, under the above experimental conditions, EIA is more likely in dry air than in humid air, possibly due to heat loss at the airway mucosa caused by evaporation. High humidity of inspired air could be the reason why EIA is less prevalent in swimming, as compared with other modes of exercise.

UI	MeSH Term	Description	Entries
D008297	Male		Males
D008450	Maximal Midexpiratory Flow Rate	Measurement of rate of airflow over the middle half of a FORCED VITAL CAPACITY determination (from the 25 percent level to the 75 percent level). Common abbreviations are MMFR and FEF 25%-75%.	Forced Expiratory Flow 025-075 Percent,FEF 25-75 Percent,Flow Rate, Maximal Midexpiratory,MMFR,25-75 Percent, FEF,25-75 Percents, FEF,FEF 25 75 Percent,FEF 25-75 Percents,Forced Expiratory Flow 025 075 Percent,Percent, FEF 25-75,Percents, FEF 25-75
D008451	Maximal Voluntary Ventilation	Measure of the maximum amount of air that can be breathed in and blown out over a sustained interval such as 15 or 20 seconds. Common abbreviations are MVV and MBC.	Maximal Breathing Capacity,MVV (Ventilation),Breathing Capacities, Maximal,Breathing Capacity, Maximal,Capacities, Maximal Breathing,Capacity, Maximal Breathing,Maximal Breathing Capacities,Maximal Voluntary Ventilations,Ventilation, Maximal Voluntary,Ventilations, Maximal Voluntary,Voluntary Ventilation, Maximal,Voluntary Ventilations, Maximal
D002648	Child	A person 6 to 12 years of age. An individual 2 to 5 years old is CHILD, PRESCHOOL.	Children
D002980	Climate	The longterm manifestations of WEATHER. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)	Climates
D005082	Physical Exertion	Expenditure of energy during PHYSICAL ACTIVITY. Intensity of exertion may be measured by rate of OXYGEN CONSUMPTION; HEAT produced, or HEART RATE. Perceived exertion, a psychological measure of exertion, is included.	Physical Effort,Effort, Physical,Efforts, Physical,Exertion, Physical,Exertions, Physical,Physical Efforts,Physical Exertions
D005260	Female		Females
D005541	Forced Expiratory Volume	Measure of the maximum amount of air that can be expelled in a given number of seconds during a FORCED VITAL CAPACITY determination . It is usually given as FEV followed by a subscript indicating the number of seconds over which the measurement is made, although it is sometimes given as a percentage of forced vital capacity.	Forced Vital Capacity, Timed,Timed Vital Capacity,Vital Capacity, Timed,FEVt,Capacities, Timed Vital,Capacity, Timed Vital,Expiratory Volume, Forced,Expiratory Volumes, Forced,Forced Expiratory Volumes,Timed Vital Capacities,Vital Capacities, Timed,Volume, Forced Expiratory,Volumes, Forced Expiratory
D006339	Heart Rate	The number of times the HEART VENTRICLES contract per unit of time, usually per minute.	Cardiac Rate,Chronotropism, Cardiac,Heart Rate Control,Heartbeat,Pulse Rate,Cardiac Chronotropy,Cardiac Chronotropism,Cardiac Rates,Chronotropy, Cardiac,Control, Heart Rate,Heart Rates,Heartbeats,Pulse Rates,Rate Control, Heart,Rate, Cardiac,Rate, Heart,Rate, Pulse
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man