The filming and photography protocol

The analysis measures your body angles from the image — so any variation in filming conditions becomes variation in the measurements. The protocol below takes ~10 minutes and guarantees two things: trustworthy recommendations and valid before/after comparisons.

Footage outside the protocol isn't rejected automatically, but the analysis confidence indicator will be weaker and we may ask you to re-record — a slightly tilted camera, loose clothing or a "cold" recording can shift the angles by several degrees, enough to change the recommendation.

Setup (once per session)

1. Bike on a trainer, on a level surface. Front wheel (or riser block) level with the rear axle; check with a spirit level or your phone's level app on the top tube.
2. Camera completely fixed, correctly placed: landscape, 2.5–3 m from the bike, at your hip height when seated, perpendicular to the plane of the bike. Entire rider and both wheels in frame.
3. Have a tripod? Use it. Don't? No problem: any solution that keeps the phone completely still works just as well — leaned against a stable object (wall, speaker, heavy vase) on a table, shelf or chair, raised to the right height with books or a box; or a desk stand / car phone holder on a support at the correct height. The test is simple: once you hit REC, nobody and nothing touches the phone. The one option that doesn't work: a phone held in someone's hand — even the steadiest hand moves enough to corrupt the measurements.
4. Tight-fitting clothing, contrasting with the background (dark kit on a light background or vice versa). Loose clothing hides the hip and knee — the number one cause of poor measurements.
5. Even lighting, no light source behind you from the camera's perspective.
6. Rear wheel fully visible — together with the crank length, it makes the millimeter conversion of the measurements possible.

The recording

1. Warm up for 3–5 minutes before hitting REC. Your pelvis settles on the saddle only after a few minutes of pedaling; a "cold" recording captures a position you don't actually ride in.
2. Steady cadence, ~85–90 rpm, moderate resistance. Ankle and knee angles vary with cadence and effort — comparable recordings are made under the same conditions.
3. Hands in a defined position — the same one every time. The app asks for your hand position with every upload and won't compare recordings made in different positions.
4. Look ahead, ride naturally — not at the camera, not down at the screen.
5. Record 20–30 seconds — that's 30–45 pedal revolutions, enough for a statistically stable value rather than a snapshot.

If you use photos instead of video

Everything above still applies — camera completely fixed and perpendicular, at the same distance and height, tight clothing, good light, a 3–5 minute warm-up. The single difference: instead of pedaling for 20–30 s, you stop with the crank exactly in the position the measurement requires and take the photo:

• knee: pedal at its lowest point, leg naturally extended;
• hip: pedal forward, crank horizontal;
• elbow: hands settled in your real riding position (on the hoods, or on the extensions for TT).

A photo captures a single moment, without averaging across pedal revolutions — which is why, where possible, video analysis remains the recommended option.

Quick checklist

• Bike level on the trainer, checked with a spirit level
• Phone completely fixed (tripod or stable support), landscape, 2.5–3 m, hip height, perpendicular
• Entire rider + both wheels in frame; rear wheel clearly visible
• Tight kit, contrast with the background, no backlight
• 3–5 minute warm-up
• Steady cadence ~85–90 rpm, moderate resistance
• Hands in the declared position (same on re-recording)
• 20–30 seconds of natural pedaling