Form fundamentals
Hip Rock
How much your pelvis rocks side to side (vertically) on the saddle — the classic too-high tell.
What good looks like
What it is
A stable pelvis stays quiet on the saddle. Visible vertical rocking as you pedal usually means you're reaching for the bottom of the stroke — a saddle that's too high — or compensating for a leg-length difference.
Why it matters
Hip rock causes saddle sores, lower-back fatigue, and inefficient power transfer, and is the most reliable visual sign of a too-high saddle.
How we detect it
We track your near-side hip vertically across the stroke (detrended to ignore camera motion) and report the peak-to-peak movement in centimeters. Under ~2 cm is stable.
How to fix it
Lower the saddle a few millimeters and re-check. If rock persists at a correct height, get assessed for a leg-length discrepancy and add single-leg stability work.
Recommended drills
- •Lower saddle 5-10 mm
- •Assess for leg-length discrepancy
- •Single-leg glute/core stability work
Run these 2-3x per week. Expect to feel a change in form 4-6 weeks in.