To examine the effect of watching favorite DVD (Digital Versatile Disc) during exercise on exercise economy and autonomic nervous function, we performed a pilot study in three healthy adults to undergo cardiopulmonary exercise test (CPX) with/without watching favorite DVD in a crossover design. Serial changes in plasma levels of noradrenaline and lactic acid were also assessed at rest, at maximum load, and at 20 min recovery. Systolic blood pressure (mmHg), heart rate (bpm) and exercise workload (watt) at each metabolic equivalents (Mets) (2 to 7 Mets) were serially measured and compared in each session. Workload at each Mets in DVD session tended to be higher than non-DVD session. Maximum difference in workload between the two sessions increased by 11 Watt at 5 Mets exercise. The workload at peak Mets, however, was identical in the both sessions. Heart rate at each Mets were very similar in the both sessions. Systolic blood pressure at each Mets in DVD-session were slightly higher than non-DVD session during exercise. The levels of lactic acid and noradrenalin showed similar pattern in the both sessions. In conclusion, watching favorite DVD may affect exercise economy in low to middle intensity exercise.