Abstract
Gaining insight into the prevention of localized muscle fatigue has been an urgent challenge in cycling competitions. While studies have investigated muscle coordination only in a single lower limb in order to clarify efficient pedaling, known as pedaling skills, one of the cyclists’ pedaling strategies, few studies have assumed a kind of asymmetrical muscle coordination in both the left and right lower limbs. In this paper, the authors aimed to quantify the difference in the strategy between road cyclists with different cycling experiences by investigating the structure of inter-lower limb muscle coordination. Six healthy male cyclists with different cycling experiences were volunteered: club cyclists for more than 4 years (n = 3) and elite cyclists for more than 10 years (n = 3). As they pedaled for 30 seconds under the experimental condition of 150 W at 90 rpm, we measured a total of 10 muscle activity patterns from the lower limbs by using surface electromyography and a crank rotational angle. Next, we extracted the muscle coordination to explain how both the lower limbs coordinate to employ skills by applying non-matrix factorization. The results found asymmetrical muscle activity patterns between the lower extremities regardless of cycling experience, which indicated muscle coordination compensating for the asymmetry to raise pedaling efficiency. These findings should contribute to understanding not only different pedaling strategies but also to preventing localized muscle fatigue. Future work should investigate the muscle coordination pattern of both lower limbs against the effect of muscle fatigue.
