Structure of Muscle
Muscle is made up of fibrous components termed myofibrils. Each of these is formed by a large number of sarcomeres. Each sarcomere feature repeated bands of Actin and Myosin, causing a banded apperance during microscopy.
The Sliding Filament Model
Huxley proposed that not only did muscles contract by changing the degree of overlap between the actin and myosin filaments, but the force was determined by the degree of such overlap.
Testing the Sliding Filament Model