Many people sometimes imagine if they can wield superhuman abilities like that appear in games and animation. Among these abilities, we focused particularly on representing the experience of arm stretching beyond the limits of the human body. We proposed a method for inducing a sense of arm stretching by designing the device attached to forearm and giving the user a visual cue by changing the body structure of the user's avatar in the virtual environment. Our device shifts the mass from the elbow to the wrist while stretching the skin of the forearm according to the animation in the virtual environment. The sensation of the elongation of the arm skin as well as the change in the weight of arm is thought to be the feeling when the arms are stretched out. As a result, we introduce these two mechanisms into our device, which allows the user to feel the sense of arm stretching.