The Effects of Expiratory Muscle Strength Training (EMST) in Elite College Swimmers

Swimming challenges the respiratory system due to increased hydrostatic pressure and resistance to breathing. We investigated the effects of 4 weeks EMST on maximum expiratory pressure (MEP) generating capacity of highly conditioned athletes. Varsity swimmers of the University of Florida were recruited and randomized to either EMST or air flow training (AFT) protocols. EMST was performed using pressure threshold trainers. The pressure load was set to 70–75% of the swimmer's MEP. Each week the pressure load was increased about 15%. AFT was conducted using peak flow meters and subjects were instructed to target a specific expiratory flow rate which was also increased each week about 15%. EMST and AFT were performed for 5 sets of 5 breaths with 1–2 min rest in between sets, 5 days per week for 4 weeks. MEP was measured pre‐ and post‐training. Pre‐training MEP values in all subjects were similar to non‐athletes. The increase in post‐training MEP values for EMST were significantly greater than AFT. The results demonstrate that: a) the expiratory muscle pressure generating capacity can be significantly increased in highly conditioned athletes and b) EMST is more effective in increasing MEP then AFT.