Previous studies suggested that emphasis or emotion causes changes in the hand movements of people using Japanese Sign Language. There has not been enough research on the change in signing speed (lower or higher), and there has been only a little research on the duration of sign components (words, transitions, and pauses). In this study, we analyzed the arm movement variation in relationship to the signing speed. The arm movements used to sign 20 sentences were recorded at three speeds (high, normal, and low) using a motion tracking system. We analyzed the relationship between the signing speed and the size of the gestures or the speed of the arms. We found that a change in signing speed caused mainly a change in the size of the gestures and that when the gesture was constrained by the location of the arm, the arm speed changed.