Comparison of Active, Passive, and Proprioceptive Neuromuscular Facilitation Stretching for Improving Glenohumeral Internal Rotation
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Comparison of Active, Passive, and
Proprioceptive Neuromuscular Facilitation
Stretching for Improving Glenohumeral
Internal Rotation
Jaime Hall, MS, ATC; Gretchen D. Oliver, PhD, FACSM, ATC; and Audrey J. Stone, PhD, ATC, CSCS
ABSTRACT and internal rotation restrictions. This phenomenon
The purpose of this study was to compare the effectiveness of of glenohumeral ROM restriction results in increased
active, passive, and proprioceptive neuromuscular facilitation anterosuperior shift or decreased posteroinferior slip
(PNF) stretching techniques on improving internal rotation of of the humeral head, which commonly leads to sub-
the shoulder in asymptomatic individuals. From a convenience acromial impingement.6,7 Decreased flexibility of the
sample of college students, including individuals on a particu- posterior capsule and the infraspinatus muscle are typi-
lar athletic team, 42 asymptomatic individuals volunteered to cally observed in throwing athletes.6-9 Posterior capsule
participate. A stretching intervention was implemented during tightness is often associated with glenohumeral internal
which participants performed 3 shoulder stretches by either rotation deficit (GIRD), which is the loss of internal ro-
passive, active, or PNF techniques. The results revealed signifi- tation compared with the contralateral side and is attrib-
cant differences in range of motion (ROM) over time for inter- utable to both bony and soft tissue changes.10
nal rotation among the different stretching protocols (P .01). Loss of glenohumeral internal rotation may be
However, the stretching protocol implemented, whether pas- caused by an osseous adaptation of the humerus and
sive, active, or PNF, did not significantly affect ROM for internal increased retroversion of the proximal humerus result-
rotation. The current findings revealed that active, passive, and ing in the increase in external rotation, at the expense
PNF stretching over time can elicit increases in internal rotation of internal rotation.5,10-13 In addition, a loss in gleno-
within the glenohumeral joint, and these changes are apparent humeral internal rotation that exceeds gains in external
after 1 week of stretching intervention. rotation has been associated with the soft tissue restric-
tion of the posterior capsule.10 Through the constant
repetitive nature of throwing and the susceptibility of
W
hen shoulder range of motion (ROM) and sustaining GIRD, there is a high propensity for shoul-
injury implications are examined, internal der instability (lack of humeral head movement con-
rotation deficits are of concern.1-5 Poste- trol), resulting in impingement.2,4,5 Stretching of the
rior capsule tightness results in glenohumeral flexion posterior capsule and posterior muscles of the gleno-
humeral joint has been shown to increase ROM and
Ms Hall is from Appalachian State University, Department of Athletics, decrease the risk of injury to the joint if the restriction
Appalachian State University, Boone, North Carolina; Dr Oliver is from the
is the result of soft tissues.8,11,14-20
Graduate Athletic Training Education Program and Department of Health,
Kinesiology, Recreation, and Dance, University of Arkansas, Fayetteville, Arkansas; Along with identifying the benefits of shoulder
and Dr Stone is from Penn State Hershey Heart and Vascular Institute, Hershey, stretching, the literature shows previously document-
Pennsylvania.
Received: October 24, 2011 ed different stretching procedures and the correspond-
Accepted: November 9, 2011 ing effectiveness on posterior capsule tightness.6,10,21,22
Posted Online: January 27, 2012
The authors have no financial or proprietary interest in the materials presented In an attempt to treat GIRD, it has been recommended
herein. to incorporate posterior capsular stretching.23 If poste-
Address correspondence to Gretchen D. Oliver, PhD, FACSM, ATC, 309 HPER,
1-University of Arkansas, Fayetteville, AR 72701; E-mail: goliver@uark.edu.
rior capsule tightness is truly the cause of the internal
doi:10.3928/19425864-20120127-01 rotation deficit, posterior capsule stretching should
Athletic Training & Sports Health Care | Vol. 4 No. X 2012 1Hall et al
correct the deficit as well as prevent further injury Thus, with the literature focusing on the benefits of
caused from the restriction.4 Loss of internal rotation posterior capsular stretching, as well as different types
caused by posterior capsular tightness is not perma- of stretching techniques, the purpose of this study
nent if a regular posterior capsule stretching regimen was to compare the effects of active, passive, and PNF
is implemented.10 In addition, the longer the stretching stretching techniques over time on improving shoul-
program is performed, the smaller the internal rotation der internal rotation. We hypothesized that the PNF
deficit.10 When evaluating the effects of stretching reg- stretching technique would elicit the greatest increase
imens, a 3-year intervention has been found to yield in internal rotation ROM, and these changes would be
significant improvements in the deficit, with most of seen earlier in the stretching regimen as compared with
the improvements occurring within years 2 and 3.10 the active and passive stretching groups.
Approximately 90% of all throwing athletes diag-
nosed with posterior capsule tightness have benefited METHOD
by some type of posteroinferior capsular stretching,
particularly the sleeper stretch.23,24 The sleeper stretch Study Design
is performed while lying on the side to be stretched, An observational, repeated measures design was
elevating the humerus to 90°, and then passively in- implemented to collect ROM data during a 4-week
ternally rotating the shoulder with the opposite arm, stretching intervention. Baseline ROM measurements
with or without performing scapular stabilization. were recorded on day 1 and 24 hours after the third
However, it has also been shown that the cross-body stretching session of each week for each study partici-
stretch can result in significant increases in internal ro- pant. All measurements were collected by the primary
tation.21 The cross-body stretch places the individual investigator (J.H.) and recorded by an athletic train-
in a position where the humerus is elevated to approxi- ing student. Range of motion measurements were col-
mately 90° of flexion and pulled across the body into lected using a digital inclinometer (Baseline Evaluation
horizontal adduction with the opposite arm. The dis- Instruments, White Plains, New York). Prior to all
parage of the cross-body stretch is the lack of scapular measurements, the digital inclinometer was calibrated
stabilization while performing the stretch.21 Although per the manufacturer’s guidelines.
the sleeper and cross-body stretches have been the pri-
mary stretches for the posterior capsule, their effective- Participants
ness has been debated.21,23,24 In addition to the type of From a convenience sample of college students, includ-
stretch, the stretching techniques of passive, active,10 ing individuals on a particular athletic team, 42 indi-
and proprioceptive neuromuscular facilitation (PNF) viduals (8 men, 34 women; mean age, 23.41.4 years)
stretching have also been examined for effectiveness.25-27 volunteered to participate. Of the 42 participants, 19
Deficits in internal rotation have been shown to were National Collegiate Athletic Association Division
improve from various active and passive stretching I softball athletes (throwers) (mean age, 20.91.5 years)
procedures.23 In addition, there has been suggestion of and 24 were graduate students (nonthrowers) (mean
improvements in ROM pertaining to glenohumeral in- age, 23.41.4 years). Participants were excluded if they
ternal rotation when utilizing PNF techniques with the had a history of shoulder injury, pain, or GIRD at the
2 posterior capsule stretches mentioned previously.10 time of data collection. In addition, all participants had
Apart from the studies that have focused on improv- to be shoulder injury–free for the past 6 months. Hand
ing glenohumeral internal rotation deficits, PNF uti- dominance was determined by the throwing hand of
lization has been shown to be beneficial in increasing the throwing athletes and the hand used for writing for
ROM,28 as well as yielding greater gains at a faster rate the graduate students. Forty-one of the 42 participants
than that of static stretching.11,16,19,20,26,28-36 It has been were right-hand dominant. All testing protocols used
reported that one repetition of PNF stretching is ade- in the study were approved by the university’s insti-
quate to elicit gains in ROM,37-40 with expected chang- tutional review board. Prior to participation, the ap-
es ranging from 3° to 9°, depending on the joint.37,39 proved procedures, risks, and benefits were explained
Regardless of the duration of the PNF stretching inter- to all participants. Informed consent was obtained by
vention, changes in ROM do occur.16,41,42 the participant, and the rights of the participants were
2 Copyright © SLACK IncorporatedStretches for Improving Glenohumeral Internal Rotation
1 2
Figure 1. Start of range of motion measure. Figure 2. Cross-body stretch.
protected according to the guidelines of the university's tions of 30-second holds, for a total of 3 times per week
institutional review board. for 4 weeks, at an intensity of 2 on a scale of 1 to 3. The
stretch intensity was described on a scale of 1 to 3, with
Procedure 1 = stretching sensation, 2 = intense stretch with no dis-
All participants reported to the graduate athletic train- comfort or pain, and 3 = intensive stretch with pain and
ing education classroom laboratory for preliminary discomfort. Initial baseline ROM measurements were
baseline glenohumeral ROM testing. All measurements taken on day 1 prior to any stretching and again at 24
were performed by the primary investigator, who had hours after the third stretching session of each week
established intrarater reliability on a group of 11 par- throughout the 4-week period. For the entire 4 weeks,
ticipants (22 shoulders) prior to the study (intraclass the investigator constantly monitored participant com-
correlation coefficient = 0.957; 95% confidence inter- pliance. The participants were notified at the beginning
val, 0.910-0.978). The primary investigator reported all of the study and at every ROM measurement day that
scores to an athletic training student who monitored the if they did not perform the stretches 3 times per week,
progress. Following the protocol of Kibler et al,43 the they would be excluded from the study. All participants
mean of 3 passive internal rotation measurements were were reported as compliant.
taken with the participant’s humerus abducted to 90° in The passive cross-body stretch was performed with
the frontal plane with the humerus parallel to the treat- the participant lying supine on the treatment table, hu-
ment table and the elbow flexed to 90° (Figure 1). The merus abducted and elevated to 90°, and elbow flexed to
end point of internal rotation was determined through 90°. The participant’s humerus was pushed at the distal
visual inspection of scapular movement accommoda- end nearest the elbow into horizontal adduction toward
tion. The digital inclinometer was placed on the surface the participant’s midline, keeping the elbow flexed and
at the midpoint of the anterior forearm with the digital the humerus elevated with the scapula stabilized by the
read-out screen facing the investigator. investigator (Figure 2). The cross-body active group
performed the same stretch, and with their contralateral
Stretching Intervention arm they pulled their distal humerus into horizontal ad-
Participants were randomly assigned, regardless of duction.
whether they were a throwing athlete or graduate stu- For the cross-body PNF group, participants were
dent, to 1 of 3 groups (active, passive, or PNF) with each passively stretched to their end point for 7 seconds with
group performing 3 stretches—sleeper, cross body, and the scapula stabilized; they then contracted against the
genie. The active group was given verbal instruction and investigator’s resistance for 3 seconds followed with an-
feedback by the investigator while they actively per- other passive stretch by the investigator to a new end
formed the stretches throughout the entire intervention point using the contract–relax PNF technique.10 This
program. The investigator throughout the intervention series was repeated 3 times. Contraction by the partici-
stretched participants in the passive and PNF groups. pant was a 4/5 on manual muscle test grades, meaning
All participants completed the 3 stretches for 5 repeti- that the contraction was strong enough to overcome
Athletic Training & Sports Health Care | Vol. 4 No. X 2012 3Hall et al
3 4
Figure 3. Sleeper stretch. Figure 4. Genie stretch.
gravity and some external resistance but not strong repeated measures was used to assess any differences in
enough to push out of the stretch position.44 ROM among the different stretching groups over time.
The sleeper stretch that was performed by the pas- To assess for possible differences between the throw-
sive stretching group was conducted with the partici- ing population and nonthrowing population, a series of
pant lying on the ipsilateral side of the shoulder to be two-way ANOVAs with repeated measures were used
stretched. Side lying allowed the participant’s weight for each stretch (active, passive, or PNF). A one-tailed
to stabilize the scapula. The shoulder and elbow were student t test was used to assess differences in base-
positioned at 90° flexion; the humerus was then inter- line ROM for internal rotation between throwers and
nally rotated by the investigator, moving it toward the nonthrowers. Differences between baseline ROM and
table (Figure 3). The active stretching group used their ROM reported at week 4 were found for each stretch
contralateral limb to internally rotate the humerus, type, and the reported deltas were analyzed using a
whereas the PNF group mimicked the PNF protocol one-way ANOVA with Tukey’s post hoc analysis for
repetitions as described in the cross-body stretch. pairwise comparisons when significant. Differences in
The genie stretch was performed by the passive ROM from baseline values for each week were analyzed
group with the participant positioned similarly to the using a one-way ANOVA with Tukey’s post hoc anal-
cross-body stretch lying supine. After the participant ysis for pairwise comparisons. The desired overall level
was lying supine on the treatment table with their hu- of significance was P .05. A Bonferroni adjustment
merus abducted and elevated to 90° and elbow flexed to was made due to multiple analyses, which lowered the
90° (representing the cross-body position), they began level of significance to P .01.
the genie stretch. From the cross-body position, partici-
pants placed their contralateral arm parallel to the arm to RESULTS
be stretched so that the hand of their contralateral arm Due to a concern that the throwers may have respond-
was placed over the elbow of the arm to be stretched. ed to the intervention differently than the nonthrow-
Both palms were facing out and away from their face. ers, the stretching groups were further divided into
Pressure was then applied to the dominant arm or arm two subgroups.
to be stretched by the investigator in an internal rota- No significant difference in internal rotation ROM
tional direction (Figure 4). The active group performed was noted between the throwing (65.9019.69°; n =
the same stretch but applying their own resistance with 18) and nonthrowing (73.4118.88°; n = 24) groups
the contralateral arm in an internal rotational direction, during baseline measurements (Figure 5). Internal
whereas the PNF group repeated the protocol of the rotation ROM did not significantly differ between
PNF groups for the sleeper and cross-body stretches. the throwing and nonthrowing groups for those
participating in the active (thrower: 27.4315.78°,
Statistical Analysis n = 6; nonthrower: 24.9013.35°, n = 9; P = .08),
Descriptive statistics are reported as mean and standard passive (thrower: 37.1620.62°, n = 5; nonthrower:
deviation. A 2-way analysis of variance (ANOVA) with 38.8015.51°, n = 9; P = .55), or PNF (thrower:
4 Copyright © SLACK IncorporatedStretches for Improving Glenohumeral Internal Rotation
5 6
Figure 5. Mean and standard error for internal rotation range of mo- Figure 6. Mean and standard error for changes in internal rotation
tion (ROM) for the throwing and nonthrowing populations before the range of motion (ROM) from baseline measurements combining all
stretching intervention. Both throwers and nonthrowers began the stretching techniques (active, passive, and proprioceptive neuromus-
intervention with similar internal rotation ROM. cular facilitation) for each week throughout the 4-week intervention.
* = significantly greater than preintervention (baseline measure-
23.7617.02°, n = 8; nonthrower: 21.7517.08°, n = ments) internal rotation ROM, P .01, $ = significantly greater than
the change in internal rotation ROM from baseline found at week 1,
6; P = .03, Cohen’s d = 15.8) stretching programs. Be- $$ = significantly greater than the change in internal rotation ROM
cause no differences were found between the throw- from baseline found at week 2.
ers and nonthrowers, the groups were combined for
all remaining analyses.
When analyzing for differences in ROM among the
different stretching groups throughout the duration
of the intervention, no interaction between the type of
stretch and duration of the intervention was found (P =
.37). However, the duration of the stretching interven-
tion alone did have a significant effect on ROM (P =
.0001), where the average ROM for internal rotation was
greater at each week following baseline. Figure 6 repre-
sents the difference () in ROM from baseline values for
weeks 1 through 4 (mean and standard error). Range of
7
motion measurements continued to increase significantly
Figure 7. Mean and standard error for the difference in internal rota-
from baseline through week 3. By week 4, no further gain
tion range of motion (ROM) from preintervention to postintervention
in ROM was observed. for each stretching technique (active, passive, and proprioceptive
When pre- and postintervention ROM were ana- neuromuscular facilitation). All types of stretching resulted in similar
increases in ROM from pre- to postintervention.
lyzed using the calculated deltas, the results showed
that no one type of stretch produced a greater increase
than another (active 25.9113.87, n = 15; passive internal rotation ROM. Data revealed that internal ro-
38.2116.72, n = 14; PNF 21.5316.37, n = 12; P = tation ROM increased significantly compared with the
.02, Cohen’s d = 9.2) (Figure 7). prior week until week 4. At week 4, the increases in
ROM appeared to plateau with no further gains. The
DISCUSSION 4-week stretching intervention was based on the study
Our results reveal that a 4-week stretching program by McClure et al21 who also examined stretching inter-
did allow for increases in glenohumeral internal ro- ventions in an attempt to gain glenohumeral internal
tation ROM. Of the 3 stretching techniques imple- rotation. However, our study not only examined the
mented (active, passive, and PNF), none were deemed posterior capsule stretching exercise, but it also imple-
superior to another for ability to produce greater mented different stretching techniques.
glenohumeral internal rotation ROM gains. As the Previous studies demonstrated that the PNF
stretching intervention progressed, so did the gains in stretches that incorporate a shortening contraction of
Athletic Training & Sports Health Care | Vol. 4 No. X 2012 5Hall et al
the antagonistic muscle to lengthen the target muscle als. Throwers and nonthrowers had not been com-
achieve greater gains in ROM.11,17,27,28,32,36,42 In addi- pared previously, and there were no data concerning
tion, it is known that 1 repetition of PNF is sufficient both populations. The current findings revealed that
to increase ROM with an expectant change in ROM simple passive stretching results in significant ROM
from 3° to 9°, depending on the joint.19,27,28,38-40,45 Not gain within the glenohumeral joint, thus demonstrat-
only does the implementation of PNF stretching twice ing that any form of passive, active, or PNF internal
per week improve ROM, it is strongly supported that rotation stretches would be beneficial if implemented
a single repetition effectively augments ROM.28,39,41,46 3 days a week in an attempt to achieve ROM gains.
In our study, we increased ROM an average of 9.5°
each week with the exception of week 4 when there CONCLUSION
was no further gain in ROM from week 3 over the On the basis of the current findings, all three stretch-
course of the intervention time period. ing techniques are equivalent in increasing internal ro-
It has been shown previously that a 4-week passive tation ROM in both throwers and nonthrowers over
stretching intervention for glenohumeral internal ro- the course of 4 weeks. In addition, our study revealed
tation has proven beneficial in increasing ROM.21 As that asymptomatic throwers and nonthrowers can
McClure et al21 documented, our study also revealed both benefit from 4 weeks of shoulder internal rota-
that a 4-week intervention was adequate for increases tion stretching whether it be by active, passive, or PNF
in ROM. However, our study is unique because the techniques. Therefore, further research is warranted
participant population included randomly assigned to verify the optimal stretching intervention that will
asymptomatic shoulders of both throwing and non- allow for glenohumeral internal rotation gains in not
throwing populations; yet, similar results were only asymptomatic individuals, but also in individuals
achieved. It is often speculated that an intervention experiencing GIRD. ■
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