Dance Anatomy & Kinesiology

432 Dance Anatomy and Kinesiology

and the elbow joint. Functionally, movements often

utilize joint motion combinations that simultane-

ously lengthen the muscle at one joint and shorten

the muscle at the other joint such that active insuf-

ficiency is avoided and effective force production

can proceed. For example, during pulling motions,

the extension at the shoulder lengthens the biceps

brachii (across the shoulder joint) so that sufficient

tension can be generated as the elbow flexes (which

shortens the biceps). However, in other cases such as

when lifting a dancer to the front with an underhand

grip, the biceps brachii will be shortened across both

the elbow and shoulder joints and active insufficiency

can become operative. Both active and passive insuf-

ficiency also come into play with the extrinsic muscles

of the hands, and appropriate positioning of the wrist

is often used to avoid these potential limitations.

Coordinated Movements

of Multiple Upper Extremity Joints

In functional movement, there is often an intricate

coordination between the hand, wrist, radioulnar,

elbow, and shoulder joints to facilitate successful

execution of the desired movement. In open kine-

matic chain movements, many joints often contribute

to effective positioning of the hand for manipulation

of objects. For example, the later phase of overhead

throwing often involves wrist flexion and ulnar

deviation, complemented by forearm pronation,

internal shoulder rotation, and scapular abduction

(Kreighbaum and Barthels, 1996). In dance, aesthetic

criteria are often more operative, and characteristic

placement and use of the arms are often associated

with different forms and schools of dance. For example,

classical ballet often uses a slight internal rotation at the

shoulder joint, flexion of the elbow, supination of the

forearm, and flexion of the wrist to achieve the desired

line of the arm when held out to the side such as seen

in the opening photo for chapter 1 (p. 1). An example

of stylized use of the upper extremity for flamenco

dance can be seen in figure 7.31 (p. 408), the Graham

modern dance technique in figure 7.51A, and African

dance in figure 7.51B. Development of the intricate

coordination required to achieve the given dance

aesthetic may take years of training to perfect.

Conditioning Exercises for the Upper Extremity

Unlike some of the other joints previously discussed,

for many dancers, adequate flexibility is less of an

issue in the upper extremity than strength. Because

the shoulder is designed for mobility, adequate

strength in the surrounding muscles is key for stabil-

ity and injury prevention. Furthermore, many dance

classes do not provide movements that progressively

develop strength for the upper extremity as is done

for the lower extremity. Hence, strengthening

performed outside of class is often necessary to

successfully achieve dance movements requiring

high levels of strength such as partnering or inverted

positions.

Strength Exercises

for the Upper Extremity

Selected strength exercises for the shoulder, scapula,

and elbow are provided in table 7.10, and a brief

description of their importance follows. Interested

readers are referred to texts by Kraemer and Fleck

(2005); Peterson, Bryant, and Peterson (1995); and

other resources available through the National

Strength and Conditioning Association for a

more comprehensive coverage of upper extrem-

ity strengthening exercises. When performing

strength exercises for the shoulder, it is important

to note that the resistance arm is very long when

lifting a weight with the elbow straight. Due to this

relationship, the muscle force required to support

the limb at 90° of shoulder abduction has been

calculated to be about 8.2 times the weight of the

limb (Soderberg, 1986). This means that holding a

10-pound (4.5-kilogram) weight in the hand would

require about 82 pounds (37 kilograms) of muscle

force to support that weight. Hence, to achieve the

desired benefits and avoid injury, particular care

should be taken to perform such exercises slowly,

in a controlled manner, with correct technique,

in a range in which no joint discomfort is experi-

enced, and with gradual increases of resistance in

small increments as strength gains allow. It is also

important to realize that there are great individual

differences in upper extremity strength in accor-

dance with many factors, including gender and

body type. So, for example, a male dancer with

proportionally shorter arms might be able to safely

lift a much heavier weight than a female dancer

with proportionally longer arms. In light of these

factors, many of the sample exercises given in table

7.10 utilize body weight, bands, or relatively light

dumbbells for resistance. However, dancers inter-

ested in developing greater strength are en-cour-

aged to work with a qualified exercise specialist so

that appropriate progressions can be made.

(Text continues on p. 444.)