ABSTRACT
The biomechanics of the cycling motion has been studied for decades by numerous researchers (see Gregor et al., 1991, for review). Most of these studies have assumed that lower extremity motion is restricted to the sagittal plane with a fixed hip joint position for seated cycling (Hull and Jorge, 1985; Neptune and Hull, 1995). Both strain gauge and piezoelectric load washers have been used in instrumented pedals to measure pedal forces and moments (Hull and Davis, 1981; Broker and Gregor, 1990). The progress in force pedal design has greatly enhanced the mechanical analysis of cycling, permitting the estimation of joint forces, joint moments and joint powers (Redfield and Hull, 1986; Broker and Gregor, 1994). Electromyography (EMG) studies of cycling have demonstrated the degree of cocontraction of the muscles controlling the knee joint, and have shown the importance of two-joint muscles (Gregor et al., 1985; Jorge and Hull, 1986; Ryan and Gregor, 1992; van Ingen Schenau, 1989). In order to study the contribution of specific muscle groups and their coordination, musculo-skeletal models have been used. For example, Hull and Hawkins (1990) studied muscle stretch/shorten cycles, while Yoshihuku and Herzog (1990) studied the relation between pedalling frequencies and maximum power output. The ongoing development of research methodologies and understanding of basic cycling motion provides us a good base to study cycling under different task constraints.
