Luustikulihastes

Luustikulihastes, also known as skeletal muscle, is one of the three main types of muscle tissue in the human body, alongside smooth muscle and cardiac muscle. It is responsible for voluntary movement, meaning it is under conscious control. Skeletal muscles are attached to bones by tendons, and when they contract, they pull on the bones, causing movement at the joints.

These muscles are characterized by their striated appearance under a microscope, due to the arrangement of contractile proteins actin and myosin into repeating units called sarcomeres. Skeletal muscle cells, also called muscle fibers, are long, multinucleated cells that are formed by the fusion of many smaller cells during development.

The contraction of skeletal muscle is a complex process involving the release of calcium ions, which trigger the interaction between actin and myosin filaments. This interaction generates force, allowing for movement. Skeletal muscles can contract with great force and speed, but they also fatigue relatively quickly compared to smooth or cardiac muscle.

Skeletal muscles play a vital role in posture, locomotion, breathing, and heat production. They are essential for everyday activities, from walking and running to fine motor skills like writing. The strength and endurance of skeletal muscles can be improved through regular exercise and training. Damage to skeletal muscles can occur due to injury, overuse, or disease, leading to pain, weakness, and impaired function.