Glossary / Glossary
Fitness, biomechanics, MIDA, nutrition and AI terms explained.
%MVC
BiomechanicsPercentage of Maximum Voluntary Contraction
Relative contraction intensity expressed as a percentage of MVC.
EN: %MVC
%MVV
BiomechanicsPercent of the muscle’s maximum force (F / F_max × 100)
In VibroTheory %MVV = activation × 100 = force / max-force × 100.
EN: %MVV
Active Force
BiomechanicsActive force — a product of neural activation (a), the force-length, and the force-velocity.
EN: Active Force
ATP
BiomechanicsAdenosine Triphosphate
Adenosine triphosphate — molecule providing energy for muscle contraction. Eccentric has lower ATP demand, concentric higher.
BioSim
BiomechanicsBiomechanical Simulation
Software engine for biomechanical simulation of human movement.
EN: BioSim
DeGrooteFregly
BiomechanicsDe Groote–Fregly muscle model
Muscle model with smooth analytical curves, convenient for optimization (Moco).
EN: DeGrooteFregly
EMG
BiomechanicsElectromyography
Electromyography — method of recording muscle electrical activity.
EN: EMG
F_hand_dyn
BiomechanicsDynamic (vibration) force per hand
F_hand_dyn(f) = m_app · ω² · A_hand(f) — grows with frequency with resonance peaks; the body-wide total is twice that.
EN: Dynamic hand force (Fhand dyn)
Force-Length Curve
BiomechanicsRelationship between muscle force and length; peak force occurs near optimal length.
EN: Force-Length Curve
Force-Velocity Curve
BiomechanicsRelationship between muscle force and contraction velocity: eccentric > isometric > concentric.
EN: Force-Velocity Curve
Forward Kinematics
BiomechanicsComputing body-segment positions and orientations from given joint angles.
EN: Forward Kinematics
FRF (АЧХ)
BiomechanicsFrequency Response Function
Response-to-excitation amplitude ratio as a function of frequency; in VibroTheory H(f) = A_hand(f)/A_hand(0).
EN: FRF (Frequency Response Function)
Hill Muscle Model
BiomechanicsPhenomenological muscle model: active force generator plus force-length and force-velocity curves.
EN: Hill Muscle Model
Inverse Dynamics
BiomechanicsComputing joint torques and forces from kinematics and external forces.
EN: Inverse Dynamics
ISO 2631
BiomechanicsHuman exposure to mechanical vibration (ISO)
Standard for human exposure to mechanical vibration; in VibroTheory — RMS acceleration limits for the hands.
EN: ISO 2631
Isometric
BiomechanicsIsometric contraction — the muscle produces force without changing length.
EN: Isometric
Joint Angle
BiomechanicsAngle between two body segments about a joint axis — the base DOF in a model.
EN: Joint Angle
Lever & Moment
BiomechanicsA rigid segment (lever) and the rotating moment about its joint axis.
EN: Lever & Moment