PURPOSE: To output the number of steps as points of the quantity of motion regarding a step speed and continuance by employing the constitution of a step detection part, step count part, reference count part, step count processing part, setting part, and display part.

CONSTITUTION: The number S of steps during the motion of rope skipping is detected by step detection part 4 and outputted to step count part 5. Then, the number S of steps is sent to step count processing part 6, which performs the arithmetic of the point of the quantity of the motion. Namely, the number S/t of number per hour from step count part 5 and reference time (t) from reference count part 2 are inputted to step count processing part 6, which outputs the point of the quantity of the motion at some reference time (t). This point of the quantity of the motion is integrated at intervals of reference time (t) and outputted as integrated value N2. This signal is sent to display part 8, which provides its display.