Respiratory muscle training has been proposed as a beneficial means of improving respiratory muscle function and performance in athletes. Therefore, the aim of this study was to determine the effects of a 6-wk specific respiratory muscle training program on the performance and respiratory muscle function in highly-trained rowers. Sixteen national representative rowers (8 males and 8 females) were assigned to either an experimental (RMT) or control (CON) group for 6-wks of respiratory muscle training. RMT consisted of 30 breaths (inspiratory and expiratory = 1 breath), twice daily using a commercially available respiratory muscle training device. Athletes performed a series of pulmonary function tests and an incremental VO2 max test prior to and following the experimental period. There were no statistically significant differences in any of the physiological, performance, perceptual or pulmonary function measures between RMT and CON following the training period (P>0.05). However, when comparing RMT to CON using magnitude based inferences, there was a "likely benefit" to perceived dyspnea (mean ±90%CL: -1.4 ±1.4 arbitrary units), mean heart rate (-4.1 ±4.7%) and maximum minute ventilation (-5.6 ±6.3%) during exercise. The results suggest that respiratory muscle training had little effect on exercise performance or pulmonary function in highly-trained rowers despite trends toward improvements in the perception of dyspnea and a decrease in maximum ventilation and mean heart rate during exercise.