ANALYSIS OF ELECTROMYOGRAPHY (EMG) SIGNALS AND FORCE OUTPUT PRE- AND POST-FATIGUE DUE TO REPEATED PEDAL PRESSING MOTION IMITATING A HEAVY TRAFFIC DRIVING.

The worsening of heavy traffic necessitates frequent pedal pressing, leading to muscle fatigue. Therefore, understanding muscle activation (MA) during this action enhances driving performance. This study establishes an experimental setup to analyze MA during pedal pressing and its changes on electromyography (EMG) signals of the quadriceps, gastrocnemius and soleus muscles when fatigued. Twenty male participants were requested to repetitively press the brake pedal until fatigue, simulating heavy traffic. Pedal frequencies of 20 and 40 presses per minute were used to replicate traffic variations. EMG signals revealed differential MA based on knee joint position during pedal pressing, with closer proximity to the steering wheel activating lower leg muscles more. Most participants (N = 1 2) maintained an optimal knee angle (100– 1 1 0 ∘ ), experiencing the slowest fatigue. Significant changes in median frequency and MA percentage of EMG signals were observed pre- and post-fatigue, with spectral density shifting to lower frequencies during sustained contraction. Pedal force decreased significantly during fatigue. These findings offer insights into optimizing drivers' seating positions and understanding the impact of heavy traffic on muscle fatigue. [ABSTRACT FROM AUTHOR]