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Key human anatomy and physiology principles as they relate to rehabilitation engineering
Published in Alex Mihailidis, Roger Smith, Rehabilitation Engineering, 2023
Qussai Obiedat, Bhagwant S. Sindhu, Ying-Chih Wang
The human body contains more than 600 skeletal muscles. Most of these muscles are attached to the skeleton, while a few are attached to the undersurface of the skin, such as palmaris longus in the upper limb. The primary function of skeletal muscles is to move the skeleton. In addition, muscles protect internal organs, as well as produce heat, when contracting, to help maintain body temperature (Scanlon and Sanders 2007). Generally, each skeletal muscle crosses at least one joint and has at least two tendons that attach both ends of a muscle into two different sites, the origin and insertion. The origin is the less movable or stationary attachment of the muscle, and the insertion is the more movable attachment (Lippert 2006). Typically, when a muscle contracts, the muscle shortens, moving the joint and bringing the insertion closer to the origin. Thus, muscles can only provide a pulling force and cannot generate a pushing force, and when they relax, they exert no force. However, muscle contraction does not always involve motion (Lippert 2006).
Wearable Sensors for Monitoring Exercise and Fatigue Estimation in Rehabilitation
Published in Manuel Cardona, Vijender Kumar Solanki, Cecilia E. García Cena, Internet of Medical Things, 2021
Maria J. Pinto-Bernal, Andres Aguirre, Carlos A. Cifuentes, Marcela Munera
Muscle fatigue is a transient and recoverable reduction in the force or power production in response to contractile activity. It is a symptom that makes it harder to move as normal [69]. It can originate at different motor pathway levels and is usually divided into central and peripheral components. Peripheral fatigue refers to exercise-induced processes that lead to a reduction in force production occurring at distal to the neuromuscular junction. Central fatigue refers to more centralized processes and can be defined as a progressive exercise-induced failure of voluntary activation of the muscle, which is not associated with the same reduction of maximum force obtained by stimulation [70]. Muscle fatigue is a commonly experienced phenomenon where people always feel tired and lack energy, resulting in limited performance and other strenuous or prolonged daily activities. Also, some people experience a dull aching in the muscle. It also increases and restricts daily life.
Mechanotransduction of Cardiovascular Development and Regeneration
Published in Juhyun Lee, Sharon Gerecht, Hanjoong Jo, Tzung Hsiai, Modern Mechanobiology, 2021
Quinton Smith, Justin Lowenthal, Sharon Gerecht
Mature skeletal muscle is derived from a highly proliferative population of progenitor myoblasts, with proliferation under the stimulation of growth factors from the fibroblast growth factor (FGF) family [17, 18]. Cell growth is hampered when these proliferation cues are dampened, and they undergo transcriptional modification, where they are differentiated into multinucleated myotubes. Satellite cells are quiescent stem myoblast progenitor cells that do not undergo maturation to myotubes, and they aid in skeletal muscle regeneration in response to injury, serving as the only putative stem cell population in the heart. Adult skeletal muscle is derived from differentiated myotubes that steadily become mature and grow via hypertrophy. Experimental evidence indicates that electromechanical junctions exist between cardiomyocytes and skeletal muscle, through synchrony in calcium transients, indicative of gap junction coupling. In addition to cardiomyocytes and fibroblasts, the heart contains sympathetic and vagal nerve cells, which extend throughout the myocardium [17–21].
Automated detection of muscle fatigue conditions from cyclostationary based geometric features of surface electromyography signals
Published in Computer Methods in Biomechanics and Biomedical Engineering, 2022
Divya Bharathi K, Karthick P. A., Ramakrishnan S.
Muscle fatigue is a condition in which muscles fails to generate the required force. During this condition, the subjects do not feel they could achieve the required movement range (Potvin and Bent 1997). Myoelectric manifestations of muscle fatigue are associated with the alterations in the amplitude and shape of compound motor action potentials which in turn results in the ensemble variations of features of the sEMG signals (Merletti et al. 1990; Gallina et al. 2011). It plays a vital role in the field of sports, rehabilitation and gait analysis. Infact, it is one of the major concerns in myoelectric interface when an experimental protocol is designed. Muscle fatigue is also a major symptom in nearly sixty percent of neuromuscular patients. Repeated fatigue permanently damages the muscle and sometimes it is irreversible (Wan et al. 2017). Thus, diagnosing the muscle fatigue condition at an early stage is crucial (Enoka and Duchateau 2008). To assess this condition, various methods such as isometric strength test, muscle imaging and biopsy are in practice. Surface electromyography (sEMG) is one of the commonly employed method for muscle fatigue analysis (Merletti and Farina 2016).
All-solid-state carbon-nanotube-fiber-based finger-muscle and robotic gripper
Published in International Journal of Smart and Nano Materials, 2022
Xia Liu, Hua Ji, Boyan Liu, Qingsheng Yang
In the human muscular system, muscle tissue can be categorized into one of three types: skeletal, cardiac, and smooth. Muscles typically work in pairs consisting of both flexors and extensors. The flexors contract and pull on the bone, which produces a movement of the joint. When the movement is completed, the flexors relax, and the extensors contract to either extend or straighten the bones. In other words, they can move limbs only via contraction and followed relaxation, they can never push bones back to their original position. For this reason, human palm muscles consist of antagonistically arranged flexors and extensors that enable the fingers to bend toward the palm. Today, artificial muscles are already available, which can be used to replace human muscles. It is also feasible to design flexible artificial muscle-structures that mimic the musculoskeletal system.
Weightlifting load effect on intra-limb coordination of lower extremity during pull phase in snatch: Vector coding approach
Published in Journal of Sports Sciences, 2019
Sung-Min Kim, Ki-Kwang Lee, Wing-Kai Lam, Wei Sun
The human body contains more than 800 muscles that produce various joints/segments actions and body movements for locomotion (Robertson, Caldwell, Hamill, Kamen, & Whittlesey, 2014). To achieve smooth and goal-directed movements, various degrees of freedom at each motor unit, muscle, segment and joint should be integrated into the comprehensive functional units (Kugler, Kelso, & Turvey, 1980). Good intra-limb coordination is related to greater force and power generations of a snatch (Campos et al., 2006). The previous studies indicated that the elite athletes started hip and knee extension and plantarflexion at the first pull phase and then increased hip acceleration and perform another knee flexion at the transition phase (Baumann, Gross, Quade, Galbierz, Schwirtz, 1988; Dvorkin, 1983). While most of the previous research investigated only the joint angles and accelerations at each phase of a snatch (Harbili, 2012; Isaka, Okada, & Funato, 1996; Kipp, Harris, & Sabick, 2011), the information of intra-limb coordination is lacking in the literature. Therefore, a comprehensive investigation of intra-limb coordination would provide insights for snatch techniques across various lifting loads.