Pelvic Tilt

Why this matters

The pelvis is the platform the hip works from. As the leg travels behind the body at push-off, the hip should extend — but the amount of extension available is limited by hip-flexor length and by how well the trunk and glutes hold the pelvis steady. When it runs out, the pelvis rotates forward to make up the difference, and the movement that looks like hip extension is really lumbar extension.

That substitution is why this is measured at toe-off rather than midstance. At midstance the pelvis sits close to neutral on most runners and the reading tells you little; at toe-off the hip is at maximum extension and the compensation shows.

• Under 10° anterior — normal. A small anterior tilt is the resting position of most pelvises.
• 10°–20° — the pelvis is rotating further forward than typical as the hip extends.
• Over 20° — a pronounced forward rotation. Expect little usable hip extension and a lower back doing work the hip should do.
• Posterior (negative) — a tucked pelvis, which closes down the front of the stride and reduces the extension available. Often a "tuck your pelvis" cue taken too far.

What good looks like

Lateral view at toe-off — the last frame the foot is still on the ground. The belt line sits close to level, the hip is visibly open behind the body, and the low back keeps its normal curve rather than arching to let the leg travel back.

Common faults

• Clicking front-then-back. The click order carries the sign: PSIS first, ASIS second. Reversed, an anterior tilt reads as posterior.
• Reading the waistband. Shorts ride up and sit at different heights front and back. Find the bony points — the ASIS at the front of the hip, the dimple at the back of the belt line.
• Picking the wrong frame. Measured before toe-off, the hip has not reached full extension and the tilt is under-read.
• Treating the thresholds as settled. They come from a markerless system that fits its own pelvis segment. Check them against a few of your own clips before acting on a borderline reading.

Coaching cues

• Hip-flexor mobility — held long enough to change tissue length, not a ten-second swing through. This is usually the limiting factor.
• Glute and deep-core strength — glute bridges, hip thrusts, and anti-extension work such as dead bugs, which teach the pelvis to stay put under load.
• "Ribs down, hips level" — a cue for the runner who arches the low back rather than extending the hip.

Related measurements

• Hip Extension — the reading pelvic tilt most often explains. A good-looking hip extension angle on a forward-rotated pelvis is borrowed from the spine.
• Trunk Forward Lean — a pelvis rotated forward often travels with a fold at the waist rather than a lean from the ankles.
• Pelvic Drop — the same bone in the other plane, seen from behind.