Spontaneous motive for continuous training is essential in health promotion. From the viewpoint of motive, a framework of performance support is required in addition to prevention of injury. In this research, we developed a wearable system named "Kyoso-kun" owing to personal training support. The system which comprises wireless sensors, audio and visual devices, provides a virtual rival who contributes a promotion of trainee's performance step by step while helping the pace setting and form. If the form tends to become unstable, the system makes trainee aware of it, and provide her/him a conscious attempt to improve the situation. Additionally the system promotes her/his motive by producing a racing against the rival. We conducted the comparative experiment for trainees who achieve a certain level of running. From the result, our proposal is same or better performance than two other methods while there is the possibility of holding down the situation of unstable form.