It is not easy to measure electrophysiological signals adequately and comfortably in real sports environments since many conventional measurement methods, such as using wired electrodes, interfere with an athlete's actions. We have developed a conductive fabric called hitoe that enables us to solve this problem because the athlete wears it. This novel wearable bioelectrode has already been put to practical use for the continuous heart rate monitoring. In the present work, we studied a way of using this bioelectrode to measure electromyographic (EMG) signals during certain sports actions such as a golf swing and a squat movement. The EMG signals in multiple muscles were measured from bioelectrodes sewed into an athlete's clothes and were transmitted wirelessly through a compact amplifier. We found that our wearable bioelectrode could obtain EMG signals with satisfactory accuracy and evaluate muscle activities under natural sports conditions, although there were certain limitations as regards electrode location (change in muscle shape) and motion type (motion speed).
