Before you start: cauda equina symptoms are an A&E emergency, not a stretching problem

Saddle numbness, bowel or bladder changes, bilateral leg pain or weakness, or progressive foot drop. Stop, go to A&E. Full list →

This is a pulse, not a hold.Nerve glides mobilise the nerve in its sheath by alternating which end is loaded. Do NOT hold the end position. Sustained traction on an irritated nerve makes the irritation worse. The therapeutic effect is the sliding motion itself, not the end-range stretch. Ten gentle reps, two seconds each direction.

How to do it

1
Sit upright on a chair, both feet flat, back unsupported
Seated upright
2
Slump forward slightly and tuck your chin to your chest
Slump and tuck
3
Slowly straighten your right knee while simultaneously lifting your chin and looking up
Knee straight, chin up
4
Slowly bend the knee back down while tucking the chin again. This is one rep
Reverse: chin down, knee bent
5
Do not hold either end position. Ten gentle reps, two seconds each direction. Switch sides
Glide, do not hold

What you should feel

A gentle pulling or sliding sensation in the back of the leg or behind the knee. The point is mobility, not stretch. There should be no sharp pain at any point in the range.

Red flag · stop if this happens

This is a glide, not a stretch. Do NOT hold the end position. Holding the position adds neural tension which is exactly what an irritated nerve does not need. If you feel shooting pain down the leg during reps, stop immediately.

Easier

Reduce range: only extend the knee halfway, only tuck the chin slightly. The glide is in the movement itself, not the end range.

Harder

Lie supine. Lift the leg to 90 degrees, then alternate ankle dorsiflexion-plantarflexion as you cycle chin-up and chin-down.

Don't do this if

Cauda equina symptoms: A&E immediately
Acute disc herniation with severe leg pain (acute neural tension is too provoking)
Pain that increases with each repetition (stop and try the child's pose for decompression)
Foot drop or progressive weakness

The evidence

Sciatic flossing differs from a static stretch because both ends of the nerve are loaded and unloaded in opposition. The knee extension stretches the distal nerve while chin-tuck stretches the proximal end; reversing each end at the same time means the nerve slides in its sheath without sustained traction. This is critical: a chronically irritated nerve responds badly to sustained traction (which is what a held stretch produces).

Citation: Coppieters MW, Butler DS (2008). Do "sliders" slide and "tensioners" tension? An analysis of neurodynamic techniques and considerations regarding their application. Manual Therapy

Routines that use this stretch

4-Minute Acute Flare Routine 8-Minute Piriformis-Bias Routine 8-Minute Disc-Bias (McKenzie) Routine 12-Minute Maintenance Routine

Last reviewed 2026-05-12

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Written by Oliver Wakefield-Smith, Founder of Digital Signet

Not a clinician. Every clinical claim on this site links to its primary source. If pain shoots down your leg, see a physiotherapist before continuing. Email corrections, fixed within 24 hours.