Technology

Science-Driven Bike Fitting

FitMetrix combines multi-camera 3D motion capture, real-time pose estimation, and an evidence-based rules engine to deliver objective, repeatable bike fits grounded in biomechanics — not guesswork.

Mechanistic Biomechanics

FitMetrix rules are grounded in mechanistic biomechanics rather than any single branded fitting methodology. Angle targets preserve clinically validated joint ranges of motion.

Age-Adjusted Targets

Built-in age adjustments account for documented physiological changes in flexibility, ensuring fit recommendations remain appropriate across the full spectrum of riders.

Saddle-Height-First Hierarchy

The adjustment hierarchy follows the principle that saddle height (knee extension) is foundational. All downstream adjustments are resolved only after the saddle position is optimized.

Methodology Agnostic

Consistent with best practices across IBFI, BikeFit, Retül, and independent fitting protocols — FitMetrix doesn't lock you into a single system.

Multi-Camera Motion Capture

Four Time-of-Flight cameras deliver high-fidelity depth and RGB data from every angle. Each camera tracks 33 body landmarks in real time, yielding 132 landmark observations per frame.

33

Body Landmarks per Camera

Full skeletal model covering every major joint from ankle to wrist.

Camera Views

Multi-angle coverage eliminates blind spots and self-occlusion artifacts.

Kalman

Smoothed Output

Temporal filtering removes frame-to-frame jitter for stable, reliable metrics.

SpecificationDetail
Cameras4× Time-of-Flight (ToF)
RGB Resolution3840 × 2160 (4K) @ 30 FPS
Pose Input Resolution1920 × 1080 RGB
Body Landmarks33 per camera (132 total)

7 Real-Time Biomechanical Metrics

Kalman-smoothed and percentile-gated across frame samples, these seven metrics form the backbone of every FitMetrix fit session.

1

Knee Extension Angle

Measured at bottom dead center of the pedal stroke. Foundational metric — saddle height adjustments are always resolved first.

2

Knee Flexion Angle

Measured at top dead center. Ensures adequate clearance and prevents impingement at the hip-knee chain.

3

Hip Angle

Torso-to-femur angle at the hip joint. Governs reach and comfort while protecting lower-back range of motion.

4

Ankle Angle

Dorsiflexion/plantarflexion through the pedal stroke. Detects excessive toe-pointing or heel-dropping patterns.

5

Shoulder Angle

Upper-arm position relative to the torso. Indicates whether the rider is over-reaching or too compressed on the bars.

6

Knee Tracking

Frontal-plane deviation of the knee relative to the pedal spindle. Flags valgus or varus alignment issues.

7

Trunk Angle

Inclination of the rider's torso relative to horizontal. Balances aerodynamics against sustainable comfort.

Evidence-Based Rules Engine

The FitMetrix rules engine is built on established biomechanical principles from professional bike fitting practice. It processes the seven real-time metrics, applies age-adjusted target ranges, and surfaces actionable recommendations in a clear adjustment hierarchy.

1

Capture & Filter

Raw landmark data from all four cameras is Kalman-smoothed and percentile-gated to produce stable biomechanical measurements.

2

Evaluate Against Targets

Each metric is compared to clinically validated angle ranges, adjusted for the rider’s age and flexibility profile.

3

Generate Ordered Recommendations

Adjustments are prioritized following the saddle-height-first hierarchy, ensuring foundational positions are resolved before reach, bar height, and cleat refinements.

See the Technology in Action

Schedule a demo to experience real-time motion capture and biomechanical analysis firsthand.