myology

Myology is the scientific study of muscles in living organisms, encompassing their structure, function, development, and pathology. It intersects anatomy, physiology, and biomechanics and applies to both human and animal biology as well as medical practice.

Muscle tissue includes skeletal, smooth, and cardiac types. Skeletal muscle is striated and voluntary, attached to bones; smooth muscle lines hollow organs and vessels and operates involuntarily; cardiac muscle forms the heart wall. Fibers contain myofibrils organized into sarcomeres, the basic contractile units.

Contraction arises from excitation-contraction coupling: motor neurons release neurotransmitters at neuromuscular junctions, triggering calcium release that enables actin–myosin cross-bridging and sarcomere shortening. ATP powers the cycling of cross-bridges. Fibers vary in speed and metabolism, and motor units recruit progressively to control force.

Development and adaptation include embryonic formation of fibers and postnatal growth by hypertrophy; satellite cells contribute to regeneration. Aging causes sarcopenia and strength decline. Muscles support locomotion and posture, generate heat, and assist vascular return and metabolic regulation.

Clinical myology covers disorders such as myopathies and muscular dystrophies, inflammatory myopathies, metabolic diseases, and neuromuscular junction disorders like myasthenia gravis. Diagnosis relies on biopsy, histology, electromyography, imaging, and genetic testing.

Research methods include histology, noninvasive imaging, electrophysiology, and molecular genetics. Historical contributions from anatomists and clinicians established the field, while modern myology emphasizes molecular mechanisms, biomechanics, and rehabilitation.