Turn

A pirouette turn, performed in many forms of dance, is a controlled turn on one leg. Starting position begins in a fourth position pliÐ"© while the turn is performed rising onto demi-pointe, or relevÐ"©, on the supporting leg and bringing the opposite leg into retirÐ"©. Pirouettes can be either en dehors (turning outwards) or en dedans (turning inwards) вЂ" the most common being en dehors. Arms and “spotting” are also essential factors in a pirouette turn. Correct turning technique includes a stable supporting leg, balance, quick movement of the arms, and a periodic whipping movement of the head, also known as spotting. Pirouettes can be performed with single, double, triple rotations, or more.

In this paper we will focus on a single en dehors pirouette on the right side executed in a jazz/modern dance style. All dancers, of all styles, will have their own technique of turning, but we will focus on the basic form. A single pirouette has three phases: preparatory, execution, and follow-through. We will look at each phase individually and analyze the joint motions behind every dancer’s graceful spin.

The preparatory phase begins in, what dancers call, a “fourth position pliÐ"©.” The left hip is flexed by a concentric contraction of the iliopsoas along with secondary movers such as the rectus femoris and pectineus. The tensor fascia latae muscle as well as the gluteus maximus helps stabilize the pelvis and trunk on the thighs, especially in this weight-bearing position. In reference to the right leg, the hip is extended by an eccentric contraction of the hamstrings - biceps femoris, semitendinosus, and semimembranosus - and the gluteus maximus serving as a secondary muscle. Knee flexion, present in both knees, is crucial in the preparatory phase. The hamstrings contract concentrically while the gastrocnemius assists in the flexion. Stabilizing muscles include the popliteus and tensor fasciae latae. The quadriceps femoris group (rectus femoris, vastus intermedius, vastus lateralis, and vastus medius) acts as an antagonist. The greater the knee flexion, the more force allowed for a solid pirouette turn. Following hip extension and knee flexion, the right ankle is slightly dorsiflexed. This action is mainly caused by a concentric contraction of the tibialis anterior muscle and secondary movers such as the peroneus longus, extensor digitorum longus, and extensor hallucis longus. It is also important to note, with the right foot, the five toes are planted on the ground while the heel is raised. This is because the extensor digitorum longus and extensor hallucis longus contracts concentrically in metatarsophalangeal extension. Additionally, as with all phases of a pirouette turn, posture and trunk stability are very important. All the abdominal muscles (obliquus externus abdominis, obliquus internus abdominis, rectus abdominis, and transverses abdominis) and some posterior muscles, such as the psoas and quadratus lumborum, are essential for support and balance. The erector spinae acts as an antagonist against the abdominal muscles to provide additional stability. As for the upper extremities in the preparatory phase, the left arm is abducted while the right arm experiences shoulder flexion. The left arm’s abduction includes a primary mover, the deltoid (especially the middle portion) with the supraspinatus assisting and playing a significant role in stability. The left arm is also pronated by the action of the pronator teres and pronator quadratus muscles. The right shoulder is flexed, allowing the arm to follow in front of the body in the sagittal plane. The anterior deltoid and clavicular portion of the pectoralis major play a key role in shoulder flexion. Along with those two muscles concentrically contracting, the biceps brachii and trapezius act as secondary movers. In the right arm, slight elbow flexion is present. This is made possible by, primarily, the brachialis contracting concentrically. Wrist flexion is also included in the arm preparation. The flexor carpi radialis and flexor carpi ulnaris are primary movers of this motion, by concentric contraction, while the digitorium superficialis act as secondary movers. Three antagonists of wrist flexion are extensor carpi radialis longus, carpi radialis brevis, and carpi ulnaris. Finally, the right thumb should be adducted so that it is tucked and cannot be seen from a frontal view. This is primarily done by the concentrically contracted adductor pollicis, with some help from the flexor pollicis brevis. With correct arm placement and leg positioning, this first phase, preparation, is vital to a successful pirouette turn.

The execution, or force, phase is the actual rotation of the pirouette. The momentum is made possible by the deep pliÐ"©, or knee flexion, in the preparatory phase and the arms propel the body to accomplish the rotation. The very first thing that must happen when beginning the execution is pronation of the wrist, immediately followed by wrist extension and elbow extension. Pronation is a contraction of the pronator teres and pronator quadratus, with stabilization by the anconeus. Wrist extension is essentially performed by the extensors carpi radialis longus, carpi radialis brevis, and carpi ulnaris. The triceps are the primary motion, contracting concentrically, for elbow extension, along with the secondary mover, the anconeus. As the arm is extending, it also goes into horizontal abduction. This motion is caused by the concentric contraction of the deltoid. The infraspinatus and teres minor serve as stabilizers. As soon as the right arm is horizontally abducted, the right foot is lifted off the ground going into hip and knee flexion, as well as plantar flexion. Hip flexion is caused by a concentric contraction of the iliopsoas along with secondary movers such as the rectus femoris and pectineus. The right knee flexes even more as the gastrocnemius and soleus contract concentrically as the ankle moves into plantar flexion. Simultaneously, the left knee and hip extends, slightly rotates inward, and plantar flexion occurs. The left hip is extended by the eccentric contraction of the hamstrings and concentric contraction of the gluteus maximus. The left hip also rotates inward slightly at the very beginning of the rotation by primarily, the gluteus minimus, and secondarily, the gluteus medius. At the same time, the quadriceps work as a unit through concentric contraction to extend the knee. The plantar flexion motion, known as rising into relevÐ"© by dancers, is a key factor in the execution phase. Because the plantar flexion is performed balancing on one foot, the primary muscle of the action is concentric contraction of the soleus. The gastrocnemius is a strong secondary mover. Since the base of support is so small, just the ball of the foot to be exact,

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