Forearm muscle activity during motorsport: a case study

Increased forearm activity may reflect greater steering input or control effort, which, if optimised, could reduce cornering time and thereby improve lap performance. This proof-of-concept case study aimed to quantify forearm muscle activity during two test sessions, with data-driven driver feedback in between sessions to inform steering technique. One ex-professional European karting driver was recruited for this study. A 20 Hz GPS was mounted on the kart, and two electromyography sensors were attached to the left and right flexor digitorum superficialis. In session one, the driver completed 19 laps; EMG data from the fastest lap (51.99 s) were analysed and used to provide feedback. In session two, the driver completed 20 laps, achieving a best time of 51.60 s. EMG analysis revealed greater left forearm activity during left-hand corners in session one, shifting to greater right forearm activity during right-hand corners in session two. The 0.39 s improvement in lap time suggests that EMG-informed feedback may influence steering technique and enhance performance. These findings highlight the potential of integrating EMG analysis into driver coaching, particularly in training and qualifying contexts.