To detect biceps fatigue, we need to collect a sufficient amount of concentration biceps curls to construct our dataset. During the recording sessions, we placed one 50Hz inertial measurement unit (IMU) (Neblina) on the volunteer's wrist, which contains a 3-axis accelerometer, a 3-axis gyroscope, and 3-axis magnetometer. The IMU unit measures one signal for each of the three orthogonal axes per sensor type, resulting in nine signals per IMU. Also, we placed the Apple Watch Series 4 on the opposite wrist to measure volunteer's heart rate, where it calculates the number of times the heart beats each minute and supports a range of 30–210 beats per minute.