QOOM
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Ready assessmentAgility

Cut / Change of Direction

A cutting manoeuvre — deceleration, plant and exit.

18
metrics
0
gradable today
7
events detected
Start an assessmentMetric reference
What this test measures

What it tests, what QOOM measures, what you get

What it tests
A cutting manoeuvre — deceleration, plant and exit.
What QOOM measures
Completion time, peak velocity, energy change at the plant, foot placement, knee flexion at initiation and peak, peak dynamic knee valgus, trunk lean and flexion, torso heading through the turn.
What you get
Phase chart through the turn, joint kinematics and metric zones.
How it is captured

The protocol

Two phones on tripods, stereo-calibrated once. The protocol below is the one the analysis pipeline is written against.

Subject approaches at prescribed speed, then cuts in a pre-planned or reactive direction. Typical angles: 45, 90, or 135 degrees. One trial per direction/leg.

Category
Agility
Environment
Overground
Trial structure
One timed trial
Minimum capture
2 s

Camera setup guide

Events detected

The moments the analysis finds first

Every metric is measured between events. These are detected from the reconstructed skeleton before any metric is computed.

  1. 1

    Trial Start

    trial_start

    First frame of the captured trial.

  2. 2

    Approach End

    approach_end

    Last frame of the approach phase (peak horizontal velocity).

  3. 3

    Penultimate Contact

    penultimate_contact

    Foot strike of the step before the cutting step, where braking begins.

  4. 4

    Plant

    plant

    Foot strike of the cutting leg that initiates direction change.

  5. 5

    Cut Instant

    cut_instant

    Frame where COM horizontal velocity aligns with the new direction of travel.

  6. 6

    Exit Push-Off

    exit_push_off

    First push-off step after the cut in the new direction.

  7. 7

    Trial End

    trial_end

    Last frame of the captured trial.

Every metric

The full metric list

This is the complete list the analysis produces for this assessment — the same list the metric reference documents. A metric with a reference distribution shows the direction that reads as better and the evidence level behind it; where the evidence gate withholds the zone, the reason is shown instead of a grade.

  • Completion Timems
    completion_time_ms
    Zone withheld — no recorded sourceevidence: approximate

    Total time from approach end to exit push-off.

  • Peak Velocitym/s
    peak_velocity_mps
    Zone withheld — no recorded sourceevidence: approximate

    Maximum horizontal COM velocity during the approach.

  • Energy Change (PFC)%
    energy_change_pfc_pct
    No reference distribution

    Percentage change in horizontal kinetic energy from approach end to penultimate contact.

  • Energy Change (FFC)%
    energy_change_ffc_pct
    No reference distribution

    Percentage change in horizontal kinetic energy from penultimate contact to plant.

  • Anterior Foot Placementm
    anterior_foot_placement_m
    No reference distribution

    Anterior distance of the plant foot relative to COM at plant.

  • Foot Placement at CoDm
    foot_placement_at_cod_m
    No reference distribution

    Lateral distance of plant foot relative to COM at direction change.

  • Knee Flexion at Initiation°
    knee_flexion_at_initiation_degPer side
    No reference distribution

    Knee flexion at the moment of plant.

  • Peak Knee Flexion°
    peak_knee_flexion_degPer side
    Zone withheld — no recorded sourceevidence: approximate

    Maximum knee flexion during the cutting phase.

  • Peak Dynamic Knee Valgus°
    peak_dynamic_knee_valgus_deg
    No reference distribution

    Maximum medial knee collapse during plant. The primary frontal-plane knee alignment marker of the cut.

  • Trunk Lean at CoD°
    trunk_lean_at_cod_deg
    No reference distribution

    Lateral trunk lean at cut instant.

  • Trunk Flexion at CoD°
    trunk_flexion_at_cod_deg
    No reference distribution

    Forward trunk flexion at cut instant.

  • Torso Heading at CoD°
    torso_heading_at_cod_deg
    Zone withheld — no recorded sourceevidence: approximate

    Torso rotation relative to the new travel direction at cut instant.

  • Pelvis Vertical Excursionm
    pelvis_vert_excursion_m
    No reference distribution

    Trial-aggregate range of vertical pelvis-COM motion. Indexes how much the centre of mass rises and falls relative to the support base.

  • Pelvis Lateral Excursionm
    pelvis_lateral_excursion_m
    No reference distribution

    Trial-aggregate range of medio-lateral pelvis-COM motion. Quantifies side-to-side sway, including during single-leg stance.

  • Pelvis Forward Excursionm
    pelvis_forward_excursion_m
    No reference distribution

    Trial-aggregate range of anterior-posterior pelvis-COM motion. Forward progression in gait; forward travel and braking depth in jumps.

  • Pelvis Vertical Excursion (SD)m
    pelvis_vert_excursion_sd_m
    No reference distribution

    Cross-cycle (or cross-rep) standard deviation of vertical pelvis-COM excursion. Higher SD signals movement variability.

  • Pelvis Lateral Excursion (SD)m
    pelvis_lateral_excursion_sd_m
    No reference distribution

    Cross-cycle standard deviation of lateral pelvis-COM excursion. Used as a stability marker for repeated gait/jump tasks.

  • Pelvis Forward Excursion (SD)m
    pelvis_forward_excursion_sd_m
    No reference distribution

    Cross-cycle standard deviation of forward pelvis-COM excursion. Used as a stability marker for repeated gait/jump tasks.

What the report contains

Sections of the report

The per-trial report is assembled from these sections, in this order.

  1. 1

    Key Metrics

    Headline cutting metrics.

  2. 2

    Metric Zone Overview

    All metrics as gradient zone bars.

  3. 3

    Phases & Events

    COM velocity with event markers through the cut sequence.

  4. 4

    Joint Kinematics

    Lower-body and trunk kinematics through the cut.

  5. 5

    Description of Metrics

    Full-text description of every metric in the report and what each one measures.

  6. 6

    Quality Assurance

    QA verdict, reasons, warnings, schema version, report hash.

Quality checks

What can stop a result

Each trial is checked before metrics are reported. A failed check either blocks the result or marks it partial — it is never silently graded.

  • Mean pose-estimation confidence across trial must be >= 0.60

    min_pose_confidence
    Blocked

  • No contiguous occlusion > 0.5 s on key landmarks (hip, knee, ankle)

    no_major_occlusion
    Partial

  • All 7 events must be detected with confidence >= 0.5

    cut_all_events
    Partial

  • COM heading must change by >= 30 degrees to qualify as a cut

    cut_direction_change
    Blocked

  • Peak approach velocity must be >= 1.5 m/s

    cut_min_approach_velocity
    Blocked
Blocked —
No metrics are reported for the trial.
Partial —
Metrics are reported with a warning; the affected values are flagged.
How grading is decided

When a metric gets a zone

A metric can be graded only when the norms registry holds a reference distribution for it, and a zone is shown only when the evidence gate admits that distribution’s provenance and evidence level. A distribution the gate refuses stays in the registry, auditable, with no zone.

0 of 18 metrics can be graded today

4 carry a reference distribution · 4 zones withheld by the evidence gate: 4 × no recorded source

Evidence levels behind this assessment’s reference distributions

  • published0

    Values traceable to a peer-reviewed population study. Reserved; nothing in the registry currently qualifies.

  • consensus0

    Anchored to a recognised clinical guideline or expert-consensus cutoff. Values are approximate, but the cutoff is citable.

  • approximate4

    Informal literature ranges or general-adult estimates, not validated against a specific cohort. The honest default.

  • unvalidated0

    A two-point estimate or an inferred value. A distribution is declared, but the evidence gate withholds the zone.

How the evidence gate worksFull metric reference

Run this assessment.

Two phones, one guided protocol, and a report at the end.

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