Inspiratory Muscle Fatigue Following Maximal Exercise in Moderately Trained Males and Females

Abstract

1798 Exercise-induced inspiratory muscle fatigue (IMF) has been reported in males (M) but there are few reports of IMF in females (F). The fatigability of locomotor muscle has been reported to be different between M and F, where F are more resistant to fatigue. It is not known if a gender difference exists for inspiratory muscle strength following heavy exercise. PURPOSE: To compare inspiratory muscle strength between M and F following maximal exercise. METHODS: 18 M (23 ± 3yrs; mean ± SD) and 16 F (23 ± 2yrs) completed 10 maximal inspiratory pressure (MIP) and maximal handgrip strength (HG) maneuvers to establish a baseline. Subjects then performed a progressive intensity VO2max test on a cycle ergometer. Post-exercise MIP and HG were assessed immediately following exercise and at 1, 2, 3, 4, 5, 10, and 15 min. RESULTS: VO2max relative to fat-free mass was not different between M (62 ± 7ml.kg−1. min−1) and F (60 ± 8ml. kg−1. min−1). M had higher absolute MIP values (−cmH2O) than F at all time intervals. 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 M and F throughout the 15 min (P<0.05). Differences for MIP between M and F were not statistically significant at any measurement time (P>0.05). CONCLUSION: IMF was observed immediately following maximal exercise in both M and F and the pattern of recovery was the same between genders.