Glossary / Glossary
Fitness, biomechanics, MIDA, nutrition and AI terms explained.
MergedV6
BiomechanicsMerged model version 6
Internal unified Samson-fit musculoskeletal model (version 6).
EN: MergedV6
Micro-damage
BiomechanicsMicroscopic muscle fiber damage
Microscopic damage to muscle fibers, primarily during eccentric contractions. Stimulates hypertrophy through inflammation and repair.
Millard Muscle
BiomechanicsMillard muscle model
Millard's aggregate muscle model with elastic tendon, implemented in OpenSim.
EN: Millard Muscle
Moment Arm
BiomechanicsPerpendicular distance from the muscle line of action to the joint axis, determining the torque.
EN: Moment Arm
Muscle Activation
BiomechanicsFraction of maximum force the muscle currently produces.
EN: Muscle Activation
MVC
BiomechanicsMaximum Voluntary Contraction
Maximum Voluntary Contraction — the greatest force a person can consciously generate.
EN: MVC
OpenSim
BiomechanicsOpen Simulation
Open-source platform for biomechanical modelling of the musculoskeletal system.
EN: OpenSim
Optimal Fiber Length
BiomechanicsFiber length at which the muscle produces maximal active force.
EN: Optimal Fiber Length
Passive Force
BiomechanicsPassive force — elastic tension depending only on the stretch.
EN: Passive Force
PCSA
BiomechanicsPhysiological Cross-Sectional Area
Physiological cross-sectional area of a muscle — determines its maximal force.
EN: PCSA
Pennation Angle
BiomechanicsAngle between muscle-fibre direction and the tendon line of action.
EN: Pennation Angle
QP Solver
BiomechanicsQuadratic Programming Solver
Quadratic programming solver for distributing muscle forces.
EN: QP Solver
Rigid Tendon
BiomechanicsSimplified muscle model with a non-deforming tendon — fiber length is a function of the musculotendon length.
EN: Rigid Tendon
ROM
BiomechanicsRange of Motion
Range of motion in a joint — the full span of achievable angles.
EN: ROM
Static Optimization
BiomechanicsMethod to compute muscle forces from joint torques without activation dynamics.
EN: Static Optimization
Tempo
BiomechanicsTempo of an exercise — speed and rhythm of each movement phase. The classic notation uses three digits: eccentric-pause-concentric.
EN: Tempo
Tendon Slack Length
BiomechanicsTendon length at which it begins to develop passive tension.
EN: Tendon Slack Length
Активация мышцы
BiomechanicsNormalized excitation level a ∈ [0, 1]
Muscle recruitment level; force F = a × F_max (with the force–length curve and moment arm). Static optimization minimizes Σa².
EN: Muscle activation
Апоневроз
BiomechanicsA flat tendon — the continuation of stabilizer muscles (rectus, erectors, gastrocnemius).
EN: Aponeurosis
Демпфирование (ζ)
BiomechanicsRelative damping ratio
ζ sets the FRF resonance peak height; VibroTheory uses ζ = 0.25 (modal, all assembly modes).
EN: Damping ratio (zeta)