A comparison of inspiratory muscle fatigue following maximal exercise in moderately trained males and females.

Exercise-induced inspiratory muscle fatigue (IMF) has been reported in males but there are few reports of IMF in females. It is not known if a gender difference exists for inspiratory muscle strength following heavy exercise, as is reported in locomotor muscles. Therefore, the relationship between fatigue and subsequent recovery of maximal inspiratory pressure (MIP) following exercise to maximal oxygen consumption (VO2max) was examined in a group of moderately trained males and females. Eighteen males (23+/-3 years; mean +/- SD) and 16 females (23+/-2 years) completed ten MIP and ten maximal handgrip (HG) strength maneuvers to establish baseline. Post-exercise MIP and HG were assessed successively immediately following a progressive intensity VO2max test on a cycle ergometer and at 1, 2, 3, 4, 5, 10, and 15 min. VO2max, relative to fat-free mass was not statistically different between males (62+/-7 ml kg(-1) min(-1)) and females (60+/-8 ml kg(-1) min(-1)). Males had higher absolute MIP values than females at all time intervals (P<0.05). Immediately following exercise, MIP was significantly reduced in both genders (M=83+/-16%; F=78+/-15% of baseline) but HG values were not different than resting values. MIP values remained depressed for both males and females throughout the 15 min (P<0.05). Differences for MIP between males and females were not statistically significant at any measurement time (P>0.05). The findings in this study conclude that IMF, observed immediately following maximal exercise, demonstrated the same pattern of recovery for both genders.