Flexion and extension are integral parts of any head and neck training program. This requires that we take into account how the cervical spine moves during contractions and the affect upon the associated musculature.
Full range flexion and extension on a neck machine requires periodic inclusion of protrusion and retraction to train the entire complex. Inclusion of these exercises insures the complete range of motion that the head and neck are capable of is tended to.
When you retract your neck the lower cervical spine extends and the upper flexes. When you protrude your neck the lower cervical spine flexes and the upper cervical spine extends. Full flexion of the neck on the neck machine is a great movement for developing muscle - but only retraction takes the occiput of the head and the first cervical vertebrae (Occ-C1) and the first two cervical vertebrae (C1-C2) to their full end-range. By the same token only protrusion takes Occ-C1 and C1-C2 to their end range of extension.
Start Position of Flexion in Hole One
Begin Full Neck Flexion by First Letting the Head Retract
For retraction - during flexion use one of the first three holes on the Pendulum 4 or 5 Way Neck machine. If this is the first time doing the exercise consider starting with hole four to get use to the movement.
For each repetition let the head retract keeping good posture before beginning the positive portion of the rep. The cam is made so that when returning from a fully retracted position there is resistance as the head moves forward before the cervical spine begins to flex.
Protrusion is described below in the following video: