Residual lung volume and ventilatory muscle strength changes following maximal and submaximal exercise.
In order to evaluate a mechanism which may be responsible for the often observed acute increase in residual lung volume (RV) following exercise, 12 non-smoking males (20-30 yrs) performed two bouts of exercise on separate days; one to maximal heart rate (HRmax) and one to 85% of HRmax for 20 min. Prior to exercise and at 5, 15, 30, 60 and 120 min post-exercise, the following parameters were measured: RV, forced vital capacity (FVC), forced expiratory volume (FEV1.0), forced expiratory flow (FEF75-85), maximal expiratory pressure (PEmax), and maximal inspiratory pressure (PImax). Significant (p < 0.05) increases occurred in RV at 5, 15 and 30 min following maximal exercise and at 5 and 30 min after submaximal exercise. Changes in RV between the two exercise bouts were generally greater (p < 0.05) for maximal exercise. Accompanying the increases in RV were significant (p < 0.05) decreases in PEmax and decreases in FVC, while FEV1.0 and FEF75-85 remained generally unchanged or were slightly elevated. The data suggest that decreases in expiratory muscle strength due to fatigue may in part be responsible for increases in RV.
Cordain
L
L
Department of Exercise and Sport Science, Colorado State University, Fort Collins 80523.
Rode
E J
EJ
Gotshall
R W
RW
Tucker
A
A
D000328:Adult; D004562:Electrocardiography; D005080:Exercise Test; D005541:Forced Expiratory Volume / Q000502:physiology; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D007320:Inspiratory Capacity / Q000502:physiology; D008297:Male; D008448:Maximal Expiratory Flow Rate / Q000502:physiology; D008450:Maximal Midexpiratory Flow Rate / Q000502:physiology; D009119:Muscle Contraction / Q000502:physiology*; D010366:Peak Expiratory Flow Rate / Q000502:physiology; D005082:Physical Exertion / Q000502:physiology*; D012115:Residual Volume / Q000502:physiology*; D012132:Respiratory Muscles / Q000502:physiology*; D012420:Running / Q000502:physiology; D014109:Total Lung Capacity / Q000502:physiology; D014797:Vital Capacity / Q000502:physiology