Muscle proteins are essential components of muscle tissue, primarily responsible for muscle contraction and movement. The two main types of muscle proteins are actin and myosin. These proteins work together in a process called the sliding filament theory, where they slide past each other to shorten and contract the muscle fibers. In addition to actin and myosin, muscle proteins also include regulatory proteins like troponin and tropomyosin, which help control the contraction process. Proper nutrition, including adequate intake of amino acids, is crucial for the synthesis and repair of muscle proteins, supporting overall muscle health and function.