Dance Anatomy & Kinesiology

The Spine 109

movements, the rectus acts alone when the head lifts,
and the obliques join in when the shoulders begin to
rise. In dance, this type of movement occurs when the
dancer is rising from a supine position such as in con-
tractions commonly used in modern and jazz dance.
When standing in an erect position the situation
gets more complex. In the standing contraction
shown in figure 3.32, the abdominals would still be
used rigorously to posteriorly tilt the pelvis, flex the
spine, and pull the abdominal wall inward. In addi-
tion, a slight co-contraction of the spinal extensors
would be required to achieve the desired “lift” of
the movement and prevent the upper back from
collapsing too far forward. However, if the torso were
allowed to round forward such as in a roll-down,
the spinal extensors would be the primary muscles
working (eccentrically) to control the spinal flexion
produced by gravity. In dance, a slight co-contraction
of the abdominals is often encouraged to shape the
movement, with the head and shoulders staying close
to the lower body as the roll-down proceeds.

Spinal Extension

Extension is the return from a position of flexion
toward anatomical position or backward bending,
in the sagittal plane. When the spine is extended
beyond anatomical position the movement can be
termed hyperextension. In analysis or description of
a movement, we often simply continue to use the term
“extension” because the goal is to describe the direc-
tion of movement (extension) rather than a position.
However, at times, such as in description of a position

TABLE 3.2 Fundamental Spinal Movements and the Muscles That Can Produce Them

Spinal movement Primary muscles Secondary muscles

Flexion Rectus abdominis

External oblique abdominals

Internal oblique abdominals

Iliopsoas*

Extension Erector spinae Semispinalis

Deep posterior spinal group

Iliopsoas

Lateral flexion Quadratus lumborum

External oblique abdominals

Internal oblique abdominals

Erector spinae

Semispinalis

Deep posterior spinal group (intertransversarii and

multifidus)

Iliopsoas (lumbar lateral flexion)

Rotation External oblique abdominals

Internal oblique abdominals

Erector spinae

Semispinalis

Deep posterior spinal group (rotatores and multifidus)

*In select circumstances due to the psoas paradox.

FIGURE 3.32 Sample dance movement showing spinal

flexion.

Photo: Roy Blakey. Dancer: Douglas Nielsen in Anna Sokolow’s “The Cage The

Pond,” with Batsheva Dance Company, Tel-Aviv.

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