Protraction and Retraction

Not actually a cervical movement

Flexion, extension, lateral flexion and rotation are things the cervical spine does. Protraction and retraction are things it appears to do, produced by combining the others.

Protraction — head sliding forward, chin staying roughly level — is upper cervical extension combined with lower cervical flexion. The lower neck bends forward while the upper neck extends to keep the eyes horizontal. This is what happens when someone leans toward a screen.

Retraction — head drawing back, chin tucking slightly — is the reverse: upper cervical flexion combined with lower cervical extension.

That decomposition is not pedantry. It explains why the chin tuck feels strange to people learning it, why it is so easy to do wrong, and why it targets a muscle group that nothing else reaches well.

Why the head goes forward and stays there

The eyes want to be level. This is a strong, largely involuntary drive — the vestibulo-ocular system works to keep the visual horizon stable.

So when the lower neck flexes forward, whether to reach toward a screen or because the thoracic spine has rounded, the upper neck extends to compensate and bring the gaze back up. The result is the characteristic forward head position: neck flexed low down, extended up top, eyes level.

Held for hours, this is a sustained load. The head’s centre of mass has moved forward of the cervical spine, lengthening the moment arm, and the posterior musculature resists that continuously. The loading page covers the mechanics.

Two things are worth separating here, because they usually get conflated. The load is real physics and is not disputed. The claim that this position reliably causes pain or structural damage is considerably weaker than commonly asserted — see tech neck for what the evidence actually supports.

The chin tuck, and why it goes wrong

Retraction — usually taught as the chin tuck or craniocervical flexion — is the standard entry exercise for deep cervical flexor training, and it is the most commonly misperformed movement in neck rehabilitation.

The intended movement: a small nod at the top of the neck, as though making a double chin, drawing the head backward in space without tilting it down. The range is small. Done correctly, the sensation is a deep, low-grade effort at the front of the neck under the jaw — not a stretch at the back.

The common faults:

Tilting the head down instead of drawing it back. This is ordinary cervical flexion, which recruits the sternocleidomastoid — precisely the muscle you are trying not to use.

Using the sternocleidomastoid. If the SCM stands out visibly on either side of the neck, the superficial flexor is substituting for the deep one. This is the exact substitution pattern observed in people with chronic neck pain, so performing the corrective exercise with the faulty pattern reinforces the problem.

Pushing too hard. This is a low-load endurance exercise, not a strength exercise. Maximum effort defeats it, because the deep flexors are recruited preferentially at low intensity and the superficial muscles take over as effort rises.

Holding the breath. The scalenes assist both lateral flexion and forced breathing, so breath holding brings them in.

The practical check is simple: two fingers lightly on the sternocleidomastoid. If it bulges during the movement, the effort is too high or the direction is wrong.

What it trains

The deep cervical flexors — longus colli and longus capitis — lying directly in front of the vertebral bodies.

These matter disproportionately relative to how invisible they are. Reduced deep cervical flexor endurance is one of the most consistent findings in people with chronic neck pain, more reliable than any postural measurement. They contribute nothing to neck circumference, produce no visible change with training, and did not appear as a separate line in the MRI study that measured everything else — the deep musculature collectively grew 6.6% over twelve weeks against 1.0–2.3% in controls.

They are the reason a neck can look impressive and function poorly.

How to train it

Supine is easiest to learn. Lie on your back, head resting on the floor or a thin support. Gently nod as though tucking the chin, without lifting the head off the surface. Hold. The support removes the need to fight gravity while learning the pattern.

Duration over intensity. This is endurance work. Ten-second holds building toward longer, repeated, at an effort that stays low enough for the deep muscles to remain dominant.

Then upright, against a wall. Head lightly touching the wall, draw back gently into it.

Then unsupported, and eventually integrated into other movements — holding a gentle tuck during harness flexion work keeps the deep flexors engaged rather than letting the SCM run the movement alone. See flexion.

The Danish military aircrew protocol included “supine upper cervical flexion and extension” as its conditioning component before the loaded work — which is exactly this movement, used as preparation rather than as the main event.

Protraction, deliberately

Training protraction as a loaded movement is uncommon and there is little evidence about it.

The argument for it is that any position the neck adopts under load in life is worth having capacity in, and forward head positions occur constantly. The argument against is that protraction places the cervical spine in the combined position with the longest moment arm, and deliberately loading it there is hard to justify when the same musculature can be trained in safer configurations.

This site does not recommend loaded protraction. That is a judgement from mechanics rather than a conclusion from evidence, because the evidence does not exist either way, and the page says so rather than presenting a preference as a finding.