Range of Motion Analysis
Measure the visible 2D range of motion at the knee, hip, shoulder and elbow, track recovery from session to session and produce a report-ready summary.
How far has this tool been checked?
The measurements were checked against computer-drawn athletes whose true answers are known exactly. That shows the arithmetic and the event rules are right under clean, controlled conditions. It does not measure how well the body-tracking model sees real people (water, loose clothing, crouching, fast limbs) and has not been compared with a lab or a coach’s stopwatch. Treat the numbers as an aid, and use the confidence label beside each value.
Where the camera goes
Seen from above. Angles are measured round from the front of the athlete; 90° is square-on from the side. Reference line: direction the athlete faces.
Side view (knee, elbow, hip, general). Knee, elbow and hip bending; the limb being assessed stays nearest the camera.
How high, and how it should sit
Framing
One person, every joint needed for the test fully visible.
The 70–90% band is our own guidance. No published source gives a camera distance in metres, so use it as a starting point and adjust until the whole movement fits.
Ready to record?
Tick each item as you set it up. This is a reminder, not a lock.
0 of 10 ready
All the camera settings
Every setting shows where it came from.
- Camera height
- About joint height, with the camera fixed and level.
- From published guidance
- Distance
- No published distance exists. Stand back until the whole athlete fits with a small margin, so the athlete fills roughly 70-90% of the frame height. Use the 1x lens and move your feet, not the zoom.
- Our guidance
- Frame rate
- 30+ fps. For clips saved at 30 fps from slow motion, enter the recorded rate (for example 120 or 240).
- From published guidance
- Resolution
- 1080p recommended
- From published guidance
- Orientation
- Landscape or portrait both work.
- From published guidance
- Lens and zoom
- Use the 1x lens with no digital zoom, on a fixed, level camera or tripod.
- From published guidance
- Lighting
- Bright, even light against a plain, contrasting background.
- From published guidance
- Clothing
- Fitted clothing that contrasts with the background.
- From published guidance
- Stability
- Tripod or fixed support, level with the horizon.
- From published guidance
- Calibration
- No calibration is needed for angles. Distances and speeds need a scale (see Calibration).
- From published guidance
Before you start
- Only perform movements a surgeon or clinician has cleared.
- Use slow, comfortable repetitions with a brief hold at each end.
- Repeat sessions with the same camera position, chair, support, clothing contrast and instructions.
Safety
- Stop for pain, dizziness, instability or any other concerning symptom.
Cues for the athlete
Plain coaching cues, one thing at a time.
knee
- Sit on a stable chair. Three slow repetitions.
hip
- Use safe, stable hand support. Three controlled cycles.
shoulder
- Raise both arms out to the sides and lower them. Three controlled repetitions. Do not turn toward either side.
elbow
- Keep the upper arm still. Three slow repetitions.
General
- Five sit-to-stand repetitions, clinician-cleared, starting and ending seated with the same permitted support each time.
Why camera position matters
Research behind these rules.
2D angles are only trustworthy when the limb moves in the plane the camera sees. Camera-side joints are measured more accurately than far-side joints, and timing is only as fine as one frame.