Skeletal muscle Skeletal muscle Skeletal muscle is one of three major muscle types, the others being cardiac muscle and smooth muscle. It is a form of striated muscle tissue, which is under the voluntary control of the somatic nervous system. Most skeletal muscles are attached to bones by bundles of collagen fibers known as tendons. A skeletal muscle refers to multiple bundles (fascicles) of cells joined together called muscle fibers. The fibres and muscles are surrounded by connective tissue layers called fasciae. Muscle fibres, or muscle cells, are formed from the fusion of developmental myoblasts in a process known as myogenesis. Muscle
Anatomical terms of muscle need antagonistic pairs located in opposite sides of a joint or bone, including abductor-adductor pairs and flexor-extensor pairs. These consist of an extensor muscle, which "opens" the joint (by increasing the angle between the two bones) and a flexor muscle, which does the opposite by decreasing the angle between two bones. However muscles don't always work this way - sometimes agonists and antagonists contract at the same time to produce force, as per Lombard's paradox. Also, sometimes during a joint action controlled by an agonist muscle (see above definition of agonist), the antagonist will be slightly activated, naturally. This occurs