Not all of us can afford a real full time personal trainer. And yet weâd like somebody to keep us going as we slack off after second round of the park. So Sega Toys has a cheaper mechanical way out. The Body Trainer is a headphone that acts like your workout buddy. The small device boasts of a built-in monitor that tracks wearerâs heart rate. And since it is the music that keeps us going, the Body Trainer adjusts the tempo of the music currently on to optimize the workout. Of course like every gizmo, you need to feed in something to achieve results. Just key in your age, vital stats, the type of workout (jogging, walking, and aerobics) and the device will get down and maximize the results from your session. Designed to make sure that you donât slack off at all, the Body Trainer will hit the shelves in April. Body Trainer from Sega Toys will cost you around 5,775 yen ($54). Pick one here.