EMG and angle dataset for the balance board experiment

All subjects were instructed to maintain a balanced posture during their attempts on the balance platform. The balance of a human body is limitedly stable due to the small fulcrum, as well as the high location of the general center of mass of the body. Therefore, even the most insignificant internal or external influences can disturb the balance and result in the balance platform touching the floor. During the experimental session, we were recording EMG signals. The arrangement includes the following muscles: Tibialis Anterior (TA), Gastrocnemius Medial head (GM), Rectus Femoris Straight head (RF), Semitendinosus (ST). Before the electrodes were placed, the subject was instructed on how to selectively activate each muscle to optimize the EMG signal and minimize cross-talk from adjacent muscles during isometric contractions. The signals were acquired via the pre-gelled single-use electrodes Swaromed 1036 (Vermed, Austria) with a silver/silver chloride sensor placed on the skin above the muscle. The impedance was monitored after the electrodes were installed throughout the experiments. Usually, the impedance values varied within a 2--5 kOhm interval. The "Encephalan-EEG-19/26" (Medicom MTD company, Taganrog, Russian Federation) with a set of A-5364 cables for EMG derivations was used in the experiment. This device possessed the registration certificate of the Federal Service for Supervision in Health Care No. FCP 2007/00124 of 07.11.2014 and the European Certificate CE 538571 of the British Standards Institute. We filtered raw EMG signals with a band-pass filter with cut-off frequencies at 1 Hz (LP) and 100 Hz (HP) and with a 50 Hz notch filter embedded in the hardware-software data acquisition complex.