Identifying Fatigue in the Vastus Lateralis Muscle in Athletes Recovering from Knee Injury



In an attempt to return to exercise or sports after an injury, athletes often overdo rehabilitation. Because of this, there is a possibility of athletes further damaging their recovering muscles or joints. There are current research and projects that note when the muscle reached a state of fatigue based on root mean square (RMS) and median frequency (MF) of muscle EMG measurements after the athlete completed their rehabilitation exercises. This project describes a knee brace device to provide live biofeedback that notes when the athlete’s muscle is fatigued during the exercises. The device takes baseline fresh muscle and fatigued muscle measurements to set a fatigue threshold for each unique user. . The knee brace then uses EMG voltage and peak detection in real time to note when the muscle is fatigued. When tested, the device successfully noted when muscle fatigue was reached when compared to the raw EMGs of the test subject.



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