Purpose: The purpose of this study was to determine strength gains following expiratory muscle strength training (EMST) and to determine detraining effects when the training stimulus is removed. Method: Thirty-two healthy participants were enrolled in an EMST program. Sixteen participants trained for 4 weeks (Group 1) and 16 participants trained for 8 weeks (Group 2). All 32 participants were detrained for 8 weeks. Maximum expiratory pressure (MEP) was used to document change in expiratory muscle strength throughout the study. Results: Group 1 had a 41% increase and Group 2 had a 51% increase in MEP following the training. Mean MEP, for both groups, was significantly greater than baseline at the end of the training period (p = 0.0001), at the 4th week of detraining (p = 0.0001), and at the 8th week of detraining (p = 0.0001). The results also indicated that there was no significant difference in mean MEP between the groups at baseline, end of training, or throughout the detraining period (p = 0.960). Discussion: The results suggest that expiratory muscle strength gains following a 4- and 8-week EMST program do not differ significantly. Additionally, detraining rates do not appear to be dependent on length of training time. (Contains 3 figures and 2 tables.)