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Edith Cowan University
Research Online
ECU Publications
2005
A comparison of training methods to increase neck
muscle strength
Angus Burnett
Edith Cowan University
Fiona Naumann
Edith Cowan University
Ryan Price
Edith Cowan University
Ross Sanders
Edith Cowan University
This article was originally published as: Burnett, A. F., Naumann, F. , Price, R. , & Sanders, R. H. (2005). A comparison of training methods to increase
neck muscle strength. Work: A Journal of Assessment, Prevention and Rehabilitation, 25(3), 205-210. Original article available here
This Journal Article is posted at Research Online.
http://ro.ecu.edu.au/ecuworks/2802
Work 25 (2005) 205–210 205
IOS Press
A comparison of training methods to increase
neck muscle strength
Angus F. Burnett
a,b,∗
, Fiona L. Naumann
b
, Ryan S. Price
b
and Ross H. Sanders
c
a
School of Physiotherapy, Curtin University of Technology, Perth, Western Australia
b
School of Exercise, Biomedical and Health Sciences, Edith Cowan University, Perth, Western Australia
c
Physical Education Sport and Leisure Studies, The University of Edinburgh, Scotland, UK
Received 2 December 2003
Accepted 29 December 2003
Abstract. Objective: To compare two neck strength training modalities.
Background: Neck injury in pilots flying high performance aircraft is a concern in aviation medicine. Strength training may be
an effective means to strengthen the neck and decrease injury risk.
Methods: The cohort consisted of 32 age-height-weight matched participants, divided into two experimental groups; the Multi-
CervicalUnit(MCU)andThera-Band tubing groups (THER),and a control (CTRL)group. Tenweeksoftrainingwereundertaken
and pre-and post isometric strength testing for all groups was performed on the MCU. Comparisons between the three groups
were made using a Kruskal-Wallis test and effect sizes between the MCU and the THER groups and the THER and CTRL groups
were also calculated.
Results: TheMCU group displayed the greatestincrease in isometric strength(flexion 64.4%, extension 62.9%, leftlateral flexion
53.3%, right lateral flexion 49.1%) and differences were only statistically significant (p<0.05) when compared to the CTRL
group. Increases in neck strength for the THER group were lower than that shown in the MCU group (flexion 42.0%, extension
29.9%, left lateral flexion 26.7%, right lateral flexion 24.1%). Moderate to large effect sizes were found between the MCU and
THER as well as the THER and CTRL groups.
Conclusions: This study demonstrated that the MCU was the most effective training modality to increase isometric cervical
muscle strength. Thera-Band tubing did however, produce moderate gains in isometric neck strength.
Keywords: Neck, strength training, isometric, +Gz force, high performance pilots
1. Introduction
Neck pain and injuries are becoming more promi-
nent in Western countries, with neck complaints being
reported as one of the major causes for long-term sick
leave [3,12]. Individuals exposed to the extreme posi-
tive acceleration forces produced by current high per-
formanceaircraft are also at a substantial risk of injury.
This is a major concern in aviation medicine [9–11,21,
∗
Address for correspondence: Dr. Angus Burnett, Research Fel-
low, School of Physiotherapy, Curtin University of Technology, GPO
Box1987, Perth,WA6485, Australia. E-mail: a.burnett@curtin.edu.
au.
25]. Eighty-five percent of F/A-18 pilots in the Royal
Australian Air Force (RAAF) reported experiencing
acute G-induced neck pain during their career [20].
Similarly, 85% of pilots in the US Air Force had ex-
perienced at least one acute neck pain episode during
their career, with the yearly prevalenceof neck pain for
all pilots being approximately 57% [1]. This figure is
a markedly higher incidence than the 5.7% to 16.6%
yearly prevalence of neck pain for men reported in the
general population [21].
Strengthening the cervical musculature has been
used to decrease pain in clinical patients [3,12,13,17,
28,31] in addition to being suggested as a method to
prevent neck complaints in high performance pilots [2,
1051-9815/05/$17.00 © 2005 – IOS Press and the authors. All rights reserved
206 A.F. Burnett et al. / A comparison of training methods to increase neck muscle strength
15,24]. Neck strength may be increased through ac-
tivities that make a high demand on the neck muscula-
ture such as wrestling [30] and may also be increased
in a non-significant manner through flying high perfor-
mance aircraft [4,24]. However, there may be a period
of time prior to this activity-specific adaptation where
the spinal structures are injured due to the exposure to
excessive external forces.
To date, there has been little research conducted
into the use of neck strengthening exercises in asymp-
tomatic individuals. To increase neck strength it is
known that area-specific training is required [2,7,22,
31] and that supervision of individuals during training
will increase the potential of a training effect [2]. The
magnitude of neck strength is known to be direction
dependent, for example, it has been found in previous
research studies that cervical muscle strength in exten-
sion is greater than that found in flexion [2,3,16,23,27,
29]which can be explainedbythe relationshipbetween
muscle cross sectional area and strength [14,26].
This study compared two diverse neck strength
training modalities, one being the multi-cervical unit
(MCU) [6,8] as illustrated in Fig. 1, the other being
Thera-Band tubing (Pro-Med Products, Inc.) (Fig. 2).
The MCU is a pin-loaded machine that utilizes a me-
chanical pulley arrangement and has the ability to re-
strainthebodyandisolatethecervicalmusculaturedur-
ing specific exercise. The neck can be trained in flex-
ion, extension and lateral flexion using this device and
the intensity of muscular contraction can be adjusted
by altering the pin-loaded weight stack. Thera-Band
tubing consists of a stretchable latex rubber. This tub-
ing is able to be attached to a stationary structure and
can be attached to the head via a Velcro head band.
The tubing then offers resistance to head movement in
flexion, extension and lateral flexion. Resistance can
be adjusted by increasing either the thickness or length
of the tubing. Both training methods are currently used
in rehabilitation centres to treat patients with neck in-
jury such as whiplash associated disorders. The cost
of a MCU is expensive and requires a trained therapist
to supervise the session. In comparison, Thera-Band
tubing is inexpensive, lightweight and portable, which
makes accessibility to training much easier.
The purpose of this study was to compare the iso-
metric cervical muscle strength changes in response
to a supervised ten week training program using the
MCU and Thera-Band tubing. Information obtained
from this study may assist in identifying an effective
modeoftrainingcervicalmusclestrength. This will aid
professionalsinvolvedin exerciseprescriptionto select
Fig. 1. The Multi-Cervical Unit (MCU) training modality.
Fig. 2. The Thera-Band tubing training modality.
appropriatetraining methods to increaseneck strength,
with the long term goal of possibly preventing neck
injuries in pilots.
A.F. Burnett et al. / A comparison of training methods to increase neck muscle strength 207
2. Methods
2.1. Subjects
The initial subject cohort in this study consisted of
thirty-sixmale subjects. Thesesubjects wererandomly
divided into three groups: the MCU training group
(n =12); the Thera-Band tubing (THER) training
group (n =12); and a non-training control (CTRL)
group (n =12). Subjects were free of prior cervical
injury including whiplash, neurological impairment or
neck pain lasting for more than seven days. Additional
exclusioncriteria included; subjectswho sufferedfrom
headachesormigraines,ormusculardisordersthat may
be aggravated by exercise, or subjects that were cur-
rently engaged in neck strengthening programs. The
use of a health questionnaire aided in the collection
of height and weight details and the identification of
any prior injuries that would indicate exclusion from
the study. The study protocol was approved the Edith
Cowan University Human Research Ethics Commit-
tee. Written, informed consent was obtained from all
subjects prior to testing.
Four subjects, three from the dynaband group and
one from the controlgroup, failed to completethe neck
training program due to personal reasons. Therefore,
the final cohort consisted of; the MCU training group
(n =12), THER training group (n =9) and CTRL
group (n =11).
2.2. Experimental protocol
TheMCUwasusedtomeasurebothpre-andpostiso-
metric cervical muscle strength for all subjects in flex-
ion,extensionandlateral flexionin theneutral position.
All strength tests were performed in a blinded manner
by an experiencedphysiotherapistand subject data was
notidentifiablethroughname. Measurementofisomet-
ric neck strength using the MCU has previously been
found to possess very good to excellent reliability [6].
Subjects were strapped into the MCU in an upright po-
sition, to minimize any movementother than that of the
cervical area. Subjects were instructed to press maxi-
mally against a force pad for three seconds with either
the forehead, side or back of the head depending upon
the direction being tested. Three tests were performed
consecutively for eachprocedure with an average mea-
surementinpounds(lbs)beingrecorded. Theforcepad
waspositionedimmediatelyabovetheeyebrowsforthe
flexion tests, directly above the occipital protuberance
for the extension tests and under the top of the ear in
Table 1
Multi-Cervical Unit (MCU) and Thera-Band Tubing (THER)weekly
progressions for training intensity
Week Sets Reps MCU %max Dynaband
Level
1 2 10 24 1
2 2 10 33 2
3 3 10 46 2
4 2 10 60 3
5 3 10 74 3
6 2 10 88 4
7 3 10 96 4
8 2 10 102 5
9 3 10 106 5
10 3 10 114 6
Table 2
AnthropometricdatafortheMulti-CervicalUnit(MCU),Thera-Band
tubing (THER) and control (CTRL) groups (mean ± SD)
MCU (n =12) DYN (n =9) CTRL (n =11)
Age (yrs) 23.3 (4.0) 21.7 (3.1) 22.6 (4.4)
Height (cm) 182.1 (4.0) 181.3 (7.2) 181.6 (4.3)
Mass (kg) 78.8 (13.2) 75.8 (13.6) 76.4 (7.3)
alignment with the subject’s ear for the lateral flexion
tests.
Boththe MCU andTHER traininggroupsperformed
ten weeks of resistance training comprising two ses-
sions per week, each separated by 3–4 days, for ap-
proximately 30 minutes per session. This included 15
minutesfor warm-upandcool downand15 minutes for
trainingin the subject’s specified mode. For both train-
inggroupswarm-upconsistedoftheactiverangeofmo-
tionforflexion,extension,lateralflexion(left/right)and
rotation (left/right), followed by stretches for the neck
muscles. The training protocol (sets x reps) remained
constantbetweenthetwotraininggroupsandwasbased
upon an intensive-interval strength-endurance model
(Table 1). Each set commencedone minute fifteen sec-
onds after the previous had commenced and the speed
of eccentric and concentric phases remained constant
during the ten weeks with a count of -one- for contrac-
tion and -two-three- for the eccentric phase. These two
strength training modalities could not be recounted to
the same denomination as they have varying methods
of increasing intensity.
For training sessions on the MCU, the subjects were
strapped into the MCU in an upright position, to mini-
mize any movement other than the cervical area. Sub-
jects were instructed to adjust the pin loaded weight
stack and lift the weight stack with either the forehead,
side or back of the head. The principle of progressive
overload was employed to ensure that training loads
continuedto challenge the subjects. This was achieved
208 A.F. Burnett et al. / A comparison of training methods to increase neck muscle strength
Table 3
Mean (±SD) for isometric strength (lbs) measured pre-and post-training for Multi-
Cervical Unit (MCU), Thera-Band tubing (THER) and Control (CTRL) groups
Time Flexion Extension L/L Flexion R/L Flexion
MCU pre 13.4 (6.8) 19.5 (9.2) 16.3 (6.9) 16.0 (7.5)
(n =12) post 22.0 (9.2) 31.8 (10.3) 25.0 (9.5) 23.8 (7.4)
difference 8.6 (3.3)* 12.3 (8.8)* 8.7 (7.2)* 7.9 (7.5)
THER pre 16.9 (8.1) 20.5 (7.8) 17.1 (6.6) 18.2 (5.8)
(n =9) post 23.9 (8.1) 26.6 (9.0) 21.6 (6.0) 22.6 (7.6)
difference 7.1 (4.3)* 6.1 (6.8) 4.6 (5.0) 4.4 (5.1)
CTRL pre 16.9 (7.9) 24.0 (12.0) 17.1 (5.8) 17.7(7.1)
(n =11) post 19.0 (8.8) 24.2 (12.7) 19.0 (9.2) 20.1 (9.1)
difference 2.1 (3.9) 0.2 (6.2) 1.9 (5.1) 2.4 (4.8)
p value 0.003 0.005 0.046 0.189
d value MCU/
THER 0.40 0.79 0.62 0.52
d value THER/
CTRL 1.20 0.90 0.54 0.40
∗
Denotes significantly different (p<0.05) when compared to the CTRL group.
d value denotes effect size between MCU and THER and between the THER and CTRL
groups.
byeitherincreasingthe numberof repetitions,the num-
ber of sets, or the weight lifted.
In the THER training group, four distinct colours
of Thera-Band tubing (red, green, blue then black)
representing differing resistances were used to allow
progressive overload in training. Training progressed
weekly in a manner pre-determined by the researchers,
through increasing the density of the Thera-Band tub-
ing. Sessions utilising the blue and black dynabandin-
cludedan extraweek of trainingwhere the length of the
theratube which was previously standardised at 70 cm
was decreased by 15 cm (i.e.55 cm) in order to provide
another method of progression. The level of resistance
progressedassuch; leveloneonthe reddynaband,level
two the green dynaband, level three the blue dynaband,
level four used the shorter blue dynaband, level five
used the black and level six the short black dynaband.
2.3. Statistical analysis
Statisticalanalysiswas performedusingSPSSV10.0
for Windows. Comparisons between the three training
groupsfor age, height and weight, and pre-trainingiso-
metric neck strength at baseline, in addition to the dif-
ferencesin isometric strength from pre-topost training,
wereanalyzed using a Kruskal-Wallis test. Thelevelof
significancewassetatp<0.05. Effectsize(d)wascal-
culated for all variables between the MCU/THER and
THER/CTRL groups as the sample size was small [5].
An effect size of 0.2 was considered small, 0.5 moder-
ate and 0.8 as large [5].
3. Results
There were no significant differences between the
two experimental groups (MCU and THER) and the
CTRL group for age, height or weight. The anthropo-
metric data for the final subject cohort are detailed in
Table 2.
There were no significant difference in baseline cer-
vical isometric strength between the training and con-
trol groups. The valuesrecorded for pre-and post train-
ing and the differences between these values are pre-
sented in Table 3.
There was a statistically significant increase in iso-
metric flexion strength for both the MCU group and
THER group when compared to the CTRL group.
These increases were 64.4% for the MCU group and
42.0% for the THER group, respectively. The MCU
group also exhibited significant increases, when com-
pared to the CTRL group, in isometric extension
strengthandisometricleft/rightlateralflexionof62.9%
and 53.3%/49.1%, respectively.
4. Discussion
This study established that there was a trend towards
the MCU being the more effective training modality in
producing increases in isometric neck strength when
compared to the THER training group. Effect size cal-
culations indicated that with larger subject numbers in
eachgroup,there mayhavebeensignificant differences
found between the MCU and THER training groups.
A.F. Burnett et al. / A comparison of training methods to increase neck muscle strength 209
Consequently, the MCU would be recommended as an
effective training methodology to increase isometric
neck strength in asymptomatic subjects.
Previousresearchhas mainlyfocussed on re-training
an injured neck back to a basic functional state. Green-
wood and DeNardis [8], studied rehabilitation patients
and found highly significant improvements in neck
strength when training with the MCU. Subjects in
Greenwood’s study experienced increases in cervical
strength,rangingfrom 69.7to 71.0%. Maeda et al. [18]
alsofoundhighlysignificant gainsin isometricstrength
of the neck musculature of injured subjects in eight
weeks. They found significant increases in isomet-
ric strength, of between approximately 38%–40%. To
our knowledge there have been few studies however,
to document isometric strength gains in non-injured
necks.
In this study the THER training group showed non-
significant increases in isometric neck strength how-
ever, these strength gains were less than what was
achieved with the MCU. This was an important finding
considering the high cost of an MCU when compared
to the very low cost and portability associated with the
Thera-Bandtubing. One limitation of the currentstudy
was that the testing protocol favoured those training
on the MCU. Morrissey et al. [19] stated when dif-
ferent modes of strength training are compared, most
improvement is usually observed from the mode that
matches the testing routine. Recommendations for fu-
ture research would be to devise an alternative testing
protocoltotestbaselineandpost-trainingneckstrength,
such as the use of a neck dynamometer.
This study also found that the neck musculature can
demonstratelargeincreasesin strength overarelatively
short period of time. This successful adaptation was
conditional on an adequate training stimulus and that
the mode of training was highly specific to the cervical
musculature since general whole-body strengthening
programshavenot producedcomparablegainsincervi-
cal strength [7,19]. Recommendations from this study
are that pilots that begin flight training engage in cervi-
cal neck training 10 weeks prior to the commencement
of flying high performanceaircraft, to more adequately
prepare the neck for the stress of flying high perfor-
mance aircraft. Additionally a neck-strengtheningpro-
gram should be in place for those returning to service
after a break in flying to increase neck strength.
A further limitation of this study when considering
application to high performance pilots, was the sub-
jects volunteering for this study were not currently fly-
ing high performance aircraft. Neck training may be
impaired by simultaneous +Gz exposure during aerial
combat sorties. Thus, application of these programs
would require greater care in periodising training so
that the development of neck strength does not impede
the current flight activities of the pilots.
5. Conclusions
The application of a 10 week, twice-weekly neck
muscle resistance-training program resulted in in-
creased cervical muscular strength. It was also sug-
gested that training on the MCU may elicit a greater in-
crease in isometric cervical muscle strength than train-
ing with the Thera-Band tubing. Larger subject num-
bers may have produced a significant difference be-
tween the two training groups. Future research is
needed to establish if increasing neck strength is an
effective way to combat +Gz induced neck injuries in
pilots flying high performance aircraft.
Acknowledgements
The authors would like to thank Mark Tregurtha and
ChrisChessonofTheWhiplashCentreofWesternAus-
tralia who supervised the MCU training group, and
tested and re-tested all subjects.
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