The effects of different types of music on heart rate (HR), rating of perceived exertion (RPE), and time to exhaustion during treadmill work were determined on 24 volunteer college students (Ss). The Ss participated in three randomly assigned multistaged treadmill walk/run to exhaustion while wearing a head-set. The three treatments were: loud, fast, exciting, popular music (Type A); soft, slow, easy-listening, popular music (Type B); and no music (control). HR was recorded at 0:30 of each minute until voluntary exhaustion. RPE was obtained after the test for five different points during the test. Differences (p less than 0.10) among experimental treatments were determined by a one-way ANOVA and Newman-Keuls. HR was lower with Type B music in minutes one and six. The peak HR and the HR in the minute preceding max were higher with Type B music. Time to exhaustion was longer during the Type B music treatment than during the control treatment. RPE was lower for Type B music than control during moderate work. This study provided some support for the hypothesis that soft, slow music reduces physiological and psychological arousal during submaximal exercise and increases endurance performance.