An experiment to increase expiratory muscle strength for instrumentalists, using a high-intensity, low-repetition expiratory training method, was conducted with 40 healthy high school band players. Subjects trained five days per week for 2 weeks using four sets of six training breaths for a total of 24 training breaths with a spring-loaded pressure relief valve that provided an adjustable threshold. The training valve pressure was set at 75% of the subject's measured maximum expiratory pressure (up to 80 cm H2O). Results demonstrated that high-intensity, low-repetition expiratory exercises significantly increased expiratory pressure generating capacity in these subjects and the degree of the training effect was similar regardless of the instrument the band member played. The training effect occurred within 2 weeks of initiating expiratory muscle training. Thus, this simple method of expiratory-specific strength training is effective and efficient for increasing expiratory pressure support in high school band students and has possibilities of a respiratory support device for many high pressure generating purposes. The potential mechanisms of the training effect are discussed.