The protective effects of continuous and interval exercise in athletes with exercise-induced asthma.
To determine the effect of two forms of warm-up on postexercise bronchoconstriction in athletes with exercise-induced asthma, 12 moderately trained persons with asthma (age = 26.5 +/- 2.2 yr; height = 169.2 +/- 2.6 cm; weight = 64.3 +/- 2.6kg; VO2max = 52.7 +/- 1.3 ml.kg-1.min-1) were tested under three experimental conditions; continuous warm-up (CW), interval warm-up (IW), and control (C). CW consisted of 15 min of treadmill running at a velocity corresponding to 60% VO2max followed by an exercise challenge test (ET = 6 min at 90% VO2max). IW involved 8 x 30-s runs (1.5 min rest between bouts of exercise), at an intensity equivalent to 100% VO2max, followed by an ET. C consisted of only the ET. FEV1, FVC, and MMEFR were measured prior to the experimental conditions, repeated before the ET, and every 2 min during a 25-min passive recovery period, using a Breon spirometer. Postexercise changes in pulmonary function were recorded as the largest decrese in FEV1, FVC, and MMEFR during the recovery period, and expressed as a percentage of baseline values. Significant differences were detected in %FEV1 (34. 6,16.7,29.7: P = 0.009), %FVC (30.0,10.7,21.0: P = 0.03), and %MMEFR (50.0,30.2,43.4: P = 0.05), in comparing C, CW, and IW, respectively. Scheffe's test detected significance (P < 0.05) between C and CW for all three dependent variables; no statistical significance between C and IW or IW and CW occurred. These data indicate that a continuous warm-up of 15 min at 60% VO2max can significantly decrease postexercise bronchoconstriction in moderately trained athletes.
School of Human Kinetics, University of British Columbia, Vancouver, Canada.
D C
DC
McKenzie
S L
SL
McLuckie
D R
DR
Stirling
D000328:Adult; D000420:Albuterol / Q000627:therapeutic use; D001250:Asthma, Exercise-Induced / Q000503:physiopathology*; D001985:Bronchial Provocation Tests; D016084:Bronchoconstriction / Q000502:physiology; D004205:Cromolyn Sodium / Q000627:therapeutic use; D015444:Exercise / Q000502:physiology*; D005260:Female; D005541:Forced Expiratory Volume / Q000502:physiology; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D008297:Male; D008450:Maximal Midexpiratory Flow Rate / Q000502:physiology; D010101:Oxygen Consumption / Q000502:physiology; D011659:Pulmonary Gas Exchange / Q000502:physiology; D015657:Respiratory Transport / Q000502:physiology; D012420:Running / Q000502:physiology; D013177:Sports / Q000502:physiology*; D014797:Vital Capacity / Q000502:physiology
D004205:Cromolyn Sodium; D000420:Albuterol