During an external isometric constant torque (25% of the maximal voluntary contraction) maintained until the maximal endurance time (limit time), we analysed and compared the changes in electromyographic (EMG) activity illustrating muscular fatigue simultaneously with mechanical activity (the tangential acceleration theta") related to physiological tremor. The EMG activities recorded were of two agonistic flexors, the biceps brachii (BB) and the brachioradialis (BR) muscles and one of the main extensors, the triceps brachii (TB). The integrated EMG increase and the mean power frequency (MPF) of the power spectrum density function (PSDF) decrease were larger for BR than for BB activity. These two findings suggested a greater BR fatigability. However, it is shown that differences between BB and BR MPF changes could be related to differences in the PSDF upper frequency limit of the two muscles and also to the relative magnitude of their tremor component.
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Int J Biol Macromol
January 2025
College of Food Science, Fujian Agriculture and Forestry University, Fuzhou 350002, China; Integrated Scientific Research Base of Edible Fungi Processing and Comprehensive Utilization Technology (Ministry of Agriculture and Rural Affairs), Fuzhou 350002, China. Electronic address:
It has been well documented that a number of polysaccharides with potent free-radical scavenging capability possess notable anti-fatigue activity. Interestingly, recent evidence also suggested mixed polysaccharides derived from multiple sources may yield augmented bioactivities compared to the polysaccharides from a single source. Therefore, in the current study, we investigated the anti-oxidant and anti-fatigue activities of a blend of polysaccharides isolated from three mushrooms.
View Article and Find Full Text PDFClin Biomech (Bristol)
January 2025
Faculty of Mechanical Engineering (FEMEC), Federal University of Uberlândia, Uberlândia, MG, Brazil.
Background: Wheelchair users face various health issues, such as cardiac problems, obesity, tissue deformation, and shoulder and wrist injuries. Although the subject of ergometry is known since 1912 and the mechanic of propulsion gesture and wheelchair configuration has been studied over the years, most of the equipment found in the literature are adaptations or lack the tools for standardization of techniques. This paper aims to conduct biomechanical validation of a new wheelchair ergometer (ERGO1) designed for assessing physical fitness and muscle training of the upper limbs of people with disabilities.
View Article and Find Full Text PDFSci Data
January 2025
School of Informatics, The University of Edinburgh, Edinburgh, EH8 9AB, United Kingdom.
Myoelectric control has emerged as a promising approach for a wide range of applications, including controlling limb prosthetics, teleoperating robots and enabling immersive interactions in the Metaverse. However, the accuracy and robustness of myoelectric control systems are often affected by various factors, including muscle fatigue, perspiration, drifts in electrode positions and changes in arm position. The latter has received less attention despite its significant impact on signal quality and decoding accuracy.
View Article and Find Full Text PDFLancet Infect Dis
January 2025
Novavax, Gaithersburg, MD, USA.
Background: Authorities globally recommended a monovalent omicron XBB.1.5-based COVID-19 vaccine for the 2023-24 season.
View Article and Find Full Text PDFNeuromuscul Disord
December 2024
University of Florida College of Medicine - Jacksonville, Jacksonville, FL, USA.
Sengers Syndrome (SS) is a rare autosomal recessive mitochondrial disorder caused by mutations in the acylglycerol kinase (AGK) gene on chromosome 7, also known as cardiomyopathic mitochondrial DNA depletion syndrome (MTDPS10). This disorder disrupts mitochondrial DNA function and energy metabolism, presenting with symptoms such as congenital cataracts, hypertrophic cardiomyopathy, skeletal myopathy, exercise intolerance, and lactic acidosis. Previous research has shown SS affects oxidative phosphorylation and mitochondrial respiration, implicating the TIM22 complex and carrier import.
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