446 Dance Anatomy and Kinesiology
less use of the posterior deltoid and greater use of
the rotator cuff for external rotation.Shoulder Internal Rotators
Strengthening the shoulder internal rotators is
advisable for balance if a lot of exercises are being
performed for the shoulder external rotators or if
there is a history of shoulder injury. The shoulder
internal rotators (particularly the subscapularis) are
considered key for shoulder stability. Single-shoul-
der internal rotation (table 7.10J, p. 440) provides
an exercise that can easily be performed on the
Reformer or using an elastic band or tubing. How-
ever, with the prevalence of rolled shoulder, often it is
advisable to at least initially emphasize strengthening
the shoulder external rotators exclusively.Scapular Adductors and Scapular Depressors
Adequate strength in the scapular adductors is
important for preventing rolled shoulders and for
promoting correct arm placement during dance.
Due to the natural linking of scapular adduction with
external rotation, focusing on pulling the shoulder
blades together when performing the exercises for
the shoulder external rotators (kneeling scarecrow
[table 7.10H, p. 439] or double-shoulder external
rotation [table 7.10I, p. 439]) is a good way to
strengthen both of these muscle groups with one
exercise. The use of scapular adduction with shoulder
horizontal abduction while the torso is inclined (such
as is commonly used with rows in a gym setting) has
also been shown to be a very effective way of overload-
ing the trapezius muscle (Brunnstrom, 1972). When
performing any of these exercises, adding an upper
back arch provides a way to counter all of the ele-
ments that tend to be associated with rolled shoulder
posture (shoulder internal rotation, scapular abduc-
tion, and kyphosis) with one exercise. Furthermore,
when executing these exercises, focusing on pulling
the shoulder blades down is a good way to emphasize
strengthening the lower trapezius (scapular depres-
sor), which is important in dance for preventing
excessive elevation of the shoulders during arm
movements and shoulder impingement injury. In
addition, the press-up (table 7.10C, p. 435), previously
described for strengthening the shoulder flexors,
offers an effective exercise for both learning to acti-
vate and strengthening the scapular depressors.Scapular Abductors
Adequate strength in the scapular abductors that is
balanced with strength of the scapular adductors is
important for preventing winging of the scapulae and
for promoting proper arm placement during dance.Shoulder Adductors
Since the shoulder adductors are not a separate
muscle group, but rather reflect a pairing of flexors
and extensors working together, specific exercises
are not included for shoulder adduction in this text.
Due to the large muscles capable of producing this
movement, the greatest force can be generated with
shoulder adduction—often about twice the force that
can be generated with shoulder abduction (Hamill
and Knutzen, 1995). However, in the gym, exercises
for the shoulder adductors include lat pull-downs
and pull-downs performed with high wall pulleys.
The press-up (table 7.10C, p. 435) can also be modi-
fied by facing the fingers and bending the elbows to
the sides to encourage use of shoulder adductors.
Similarly, strengthening of the shoulder adductors
can easily be included with the curl-up performed
on the Reformer (previously described in table 3.4D
on p. 135) by pulling the arms down from shoulder
height to the sides in the frontal plane—that is,
shoulder adduction versus shoulder flexion.Shoulder External Rotators
Strengthening the shoulder external rotators should
also be a priority due to their importance in promot-
ing correct shoulder mechanics and in preventing
rolled shoulders, impingement syndrome, and other
shoulder injuries. Everyday activity does not neces-
sarily provide the desired strength for the external
rotators, and they are generally able to produce less
torque than the internal rotators or any other muscle
group of the shoulder. Furthermore, one study
showed that the ratio of internal rotation to external
rotation was about 30% higher in the dominant versus
the nondominant shoulders of 15 normal subjects,
due to higher internal rotation in the dominant versus
the nondominant arm and approximately the same
external rotation in the dominant and nondominant
arm (Warner et al., 1990). The kneeling scarecrow
(table 7.10H, p. 439) offers an effective exercise for
the shoulder external rotators that can be performed
with weights, while double-shoulder external rota-
tion (table 7.10I, p. 439) can be performed with an
elastic band.
Performing the latter exercise with the elbow
slightly in front of the torso (with the shoulder in the
plane of the scapula) will allow greater conformity
between the head of the humerus and glenoid fossa,
greater force production due to a more optimal
length of the shoulder external rotators, and more
range of motion due to slackening of the joint cap-
sule (Greenfield et al., 1990). Gently pressing your
elbow inward against your opposite hand (shoulder
adduction in the plane of the scapula) may also allow