Understanding how the human brain generates neural commands to control muscles during motor tasks still arouses great interest and curiosity among researchers. Surface electromyography represents the most widespread methodology to analyze the muscle activity due to a noninvasive technique. In the last decades, the factorization of the EMG signals by means of muscle synergies has been proposed in order to understand the neurophysiological mechanisms related to the Central Nervous System ability in reducing the dimensionality of the muscle control. The EMG factorization is used in several research fields, such as gait analysis to discriminate patients with pathologies, robotics to implement specific EMG-based controllers, and sports to prevent possible injury and to evaluate motor performance. The reliability of the muscle synergy factorization still remains an open challenge and its objective validation is needed to give an insight breakthrough in the previous research fields.

The aim of this special issue is to collect original research articles on the recent methodologies adopted to analyze EMG signals and to estimate the muscle synergy parameters during motor tasks. The issue will publish studies focused on the evaluation of reliability and robustness of muscle synergies to permit their aware use and on their applications in clinical routine, robotics, and sports. Original research contributions as well as review articles are welcome. Original contributions that are not yet published or that are not currently under review by other journals or peer-reviewed conferences are sought.

Potential topics include but are not limited to the following:

• Innovative algorithms for the extraction of muscle synergies from EMG signals
• Innovative algorithms to detect useful EMG parameters
• Guidelines of EMG postprocessing to ensure repeatability and reproducibility of the muscle synergies
• Development of robot controllers based on EMG parameters or muscle synergies
• Use of EMG parameters and muscle synergies as indices capable of discriminating different pathologies and/or different pathology severity
• Application of EMG analysis and muscle synergies in sports
• Validation of the muscle synergy theory by means of electroencephalography signals, functional Magnetic Resonance Imaging, and so on