Stochastic simulation of myosin cross-bridge cycling on actin filament. ATP hydrolysis drives the power stroke, generating force and sliding motion.
Huxley (1957) model: Cross-bridges bind actin at displacement x with rate f(x), detach with g(x).
For x∈[0,h]: f(x)=f₁·x/h, g(x)=g₁
For x<0 or x>h: f(x)=0, g(x)=g₂ (fast)
Force = κ·x per attached bridge (spring)
Fenn effect: ATP consumption ∝ f+g·n
Power stroke = conformational change after ATP→ADP+Pi. Force-velocity relation emerges from ensemble statistics.