PROBLEM TO BE SOLVED: To provide a muscle fatigue determination device and method that can generate muscle fatigue information in realtime while a user is pedalling a bicycle.SOLUTION: The muscle fatigue determination device includes an information acquisition part 400 and a muscle fatigue information generation part 399. The information acquisition part 400 acquires a load applied on a pedal 103 of a bicycle 104, a rotational speed of a crank 105 of the bicycle, and a myoelectricity of a user 100 corresponding to the load of the pedal and the rotational speed in association with each other. The muscle fatigue information generation part 399 generates muscle fatigue information of the user on the basis of whether or not a difference of a plurality of myoelectricities of the user in association with loads and rotational speeds within a predetermined range is greater than a first threshold.SELECTED DRAWING: Figure 5COPYRIGHT: (C)2016,JPO&INPIT【課題】自転車のペダリング中に筋疲労情報をリアルタイムで生成することができる筋疲労決定装置及び方法を提供する。【解決手段】自転車104のペダル103にかかる負荷と、自転車のクランク105の回転速度と、ペダルの負荷及び回転速度に対応するユーザ100の筋電とを相互に対応付けて取得する情報取得部400と、所定範囲内に含まれる負荷と回転速度とに対応付けられた、複数のユーザの筋電の差が第1閾値よりも大きいか否かに基づきユーザの筋疲労情報を生成する筋疲労情報生成部399とを備える。【選択図】図5