Active Force
Short definition
Active force — a product of neural activation (a), the force-length, and the force-velocity.
Full definition
Active force is generated only when the muscle is activated: F_active = a · f_L(length) · f_V(velocity). In Hill models it is the contractile element's contribution. At zero velocity (isometric) it lies between the eccentric and concentric values. Active force is the main target of static optimization, distributed across the muscle groups.
Examples
Biceps active force = 0.7 × 0.9 (length) × 1.0 (zero velocity) ≈ 63 % MVC.