sliding filament mechanism

Sliding-Filament Mechanism found in muscle. Muscle working mechanism is very interesting. A good explaining theory for this process like that.
Muscle contraction is produced by cross bridge cycles. A cycle has 4 steps:
(1) Energizing of myosin cross bridge
A + M•ATP —> A + M*•ADP•Pi (ATP is energizer here)
(2) Attachment of cross bridge to a thin filament
A + M*•ADP•Pi —> A•M*•ADP•Pi
(3) Movement of cross bridge, producing tension
A•M*•ADP•Pi —> A•M + ADP + Pi
(4) Detachment of cross bridge from thin filament
A•M + ATP —> A + M•ATP (ATP is modulator here)
Movement of the cross bridges make the overlapping thick and thin filaments slide past each other (they do not change in length) to produce a contraction.