It is very important to get younger adults exercising because exercise will help to increase their quality of life. Once younger adults decide to start a fitness program, every effort needs to be made to keep them from dropping out. One way to accomplish this is to give them a workout that they enjoy and that they perceive to be beneficial to their well-being. In an aerobic exercise program, preferred music may be a major contributor to making a workout more enjoyable. It also provides the rhythm needed to promote continual movements that may help to increase the heart rate, therefore, increasing the intensity of the workout. Aerobic cycling training is the exercise of choice for many younger adults who decide to start a fitness program. Some studies indicated that music had a significantly positive effect, negative effect and no effect on heart rate. The combined results of all the studies that examined music’s effect on heart rate were conflicting. Therefore, this study is to investigate preferred music’s effect on heart rate during progressives cycle exercise. The purpose of this study was to examine the preferred music's effect on heart rate of untrained young adult's male's participation during progressive ergo meters cycling. The independent variable was music and the two music conditions were preferred music and no music. The dependant variable was the heart rate, which was measured with the use of beurer heart rate monitor PM45, Beurer GmbH. Germany. The participants were 15 untrained young adult's males that randomly selected from 20 students [Age (yrs): 24.65 ± 2.41 and BMI (Kg/m2): 22.64 ± 2.58] in a stationary bike cycling class. During the first class session of the study, the participants learned how to use the heart rate monitors and how to exercise with stationary bike cycle (Elema – Schonander, EM.36, 1.1, FABISO3; Germany) based on the YMCA's sub maximal cycle test protocol without music. The firs workload set as warm up period . During the next class session, preferred music condition was used. Finally, during last session no music was used. The exercises and order of exercise in each session was consistent. In order to determine if music had an effect on the subject's heart rate, heart rate was measured in last 30 second of each workload. A two-tailed independent samples t test indicated no significant differences in the heart rate scores in the three workloads between training & preferred music and training & no-music conditions. A one-way ANOVA for repeated measure indicated significant differences in the heart rate scores between three workloads in the training & preferred music (P≤0.001) and the training & no-music (P≤0.001) conditions. Significant increment of mean scores of heart rate in the training & preferred music and the training & no-music conditions associated with increment of workload and intensity of cycling and significantly differences between workloads. While this study included unique participants (untrained young adult males) and unique exercise program (progressive ergo meter cycling), it was expected that the results would indicate that the use of preferred music would have not a positive effect on heart rate, but increment of workload would have a positive effect on heart rate. The participants in this study showed no significant differences in heart rate when exercising to the preferred and no music conditions. The results from this study do not add evidence that the preferred music has a significant positive effect on heart rate during exercise. Future studies may shed more light on this issue.