With this invention, the number of steps of the user during the unit time which is set beforehand calculation is done, the even step during that unit time making use of the number of steps which calculation are done, is calculated. Walking speed of the user is calculated the even step, and the calculation which it calculated making use of the number of steps which are done, from the calculation result, motion strength of the user in unit time is calculated.本発明では、予め設定した単位時間内のユーザの歩数を計数し、計数した歩数を用いて、その単位時間内における平均の歩幅を算出する。算出した平均の歩幅、及び計数した歩数を用いてユーザの歩行速度を計算し、その計算結果から、単位時間におけるユーザの運動強度を算出する。
