the increasing use of electronic screens , such as smart phones and personal computers , to 
 an average of about 8 hours per day1 , has 
 led to an increasing number of people with forward head posture ( fhp ) .
fhp is defined as the 
 anterior positioning of the cervical spine1 and is associated with muscle imbalance , pain , fatigue , and limited 
 motion of the cervical spine2 .
fhp may 
 cause herniated cervical intervertebral discs and other adverse effects , such as chronic low 
 back pain and temporomandibular disorder3 .
the craniovertebral angle ( cva ) is defined as the angle of the horizontal line running 
 through the c7 spinous process and the line connecting the c7 spinous process to the tragus 
 of the ear .
yip et al.4 reported that 
 participants with significantly smaller craniovertebral angles had fhp and tended to have 
 increased levels of neck pain .
similarly , sohn and associates5 showed that participants with smaller craniovertebral angles tended 
 to have more tension - type headaches , and lower cervical range of motion .
szeto et al.6 reported a higher frequency of neck and 
 shoulder pain in individuals who spent long periods using computers .
previous research7,8,9 suggests that weakened postural muscles 
 should be strengthened and shortened muscles should be lengthened in order to improve 
 postural alignment and alleviate fhp . a variety of therapeutic exercises designed to mitigate the symptoms of fhp have been 
 examined4 , 10 .
the majority of treatments have focused on the deep neck flexors , 
 as they play a major role in stabilizing the alignment of the cervical spine11 . however , one drawback of focusing on this 
 alignment alone is that the treatment focuses on the symptom and not the reasons why the 
 misalignment has developed .
fhp may develop due to genetic and behavioral reasons , such as 
 reading from a sitting position with reading material on a horizontal surface ; i.e. looking 
 down at a desk .
individuals may not be aware of their bad posture and thus remain in this 
 straining posture for prolonged periods .
pilates training is designed to improve general body flexibility and health by emphasizing 
 core strength , posture , and coordination of breathing with movement12 .
it improves posture by enhancing body awareness13 and can be used as self - exercise , and can 
 be easily tailored for treatment of specific postural misalignments .
based on kuo et 
 al.13 report that pilates can improve 
 thoracic kyphosis in older adults , we infer that pilates may improve cervical spine health 
 by increasing the craniovertebral angle .
therefore , this study compares the effects of 
 pilates and combined stretching and strengthening exercise programs on cva , cervical range 
 of motion ( rom ) , neck and shoulder pain , and muscle fatigue in individuals with fhp .
after the study was approved by the institutional review board of pusan national university 
 medical center ( 05 - 2011 - 038 ) , informed consent was obtained from each participant . 

participants were screened primarily on the severity of fhp ( when the tragus was in front of 
 the center of shoulder ; fig .
1.craniovertebral angle measurement ) , and secondarily via e - mail questionnaire to exclude any spinal problems , pain or 
 dysfunction or a visual analogue pain score above 3 of the neck and shoulder region , 
 temporomandibular disease , as well as any other confounding health problems .
additionally 
 any participants with experience in pilates and who were not sedentary were excluded from 
 the study . a total of twenty - eight sedentary females ( demographics shown in table 1table 1.participant demographic characteristicscharacteristicspilates groupcontrol groupno . of subjects1414age ( yrs)29.2  4.328.9  5.0height ( cm)162.0  6.9162.6  5.2weight ( kg)57.2  7.455.2
 8.7data are presented as means  sd . ) with fhp , between 23 and 39  years of age , were enrolled and randomly assigned 
 into a pilates ( pg , n=14 ) or combined ( cg , n=14 ) exercise groups .
all participants were 
 unaware of the exact exercise type until the end of testing period .
the pilates and combined 
 exercise instructors were placed in their respective areas and were blinded to the study 
 purpose .
both groups exercised for 50 minutes a day , three days a week at an intensity of 1115 
 rating of perceived exertion ( rpe ) , with added load each week for ten weeks .
the pilates 
 exercise program consisted of modern pilates that focused on balancing fhp - related major 
 muscle group - stretching of the neck extensors and pectoral muscles and strengthening of the 
 deep neck flexors , shoulder retractors , back , and abdominal muscles with co - activation of 
 the core muscles by focusing on breathing technique10 .
if 
 any motion caused pain during exercise , the participant was instructed to rest until the 
 pain subsided . the combined exercise program consisted of stretching and strengthening 
 exercises typically used to balance posture14 .
this exercise also focused on balancing the fhp - related major 
 muscle groups , although without co - activation of the core muscles .
all sessions were supervised by either pilates or exercise 
 instructors . after receiving an oral explanation and reviewing the institutional review board
fhp was determined by measuring 
 the cva15 from a sagittal plane x - ray 
 ( fig .
1 ) . to maximize compliance , participants 
 were instructed to report after work to the hospital to participate .
prior to their participation in the 
 treatment programs , cervical flexion , extension , lateral flexion , and rotation were tested 
 using crom ( performance attainment associates , mn , usa ) , which was specially designed to 
 measure cervical rom .
all cervical rom assessments were performed starting at a natural head 
 posture and explained with demonstrations .
after performing each exercise three times , the 
 average value was recorded . the visual analogue scale ( vas ) ,
a simple , sensitive , and highly 
 reproducible method for measuring pain16 , 
 was assessed before and after treatment .
likewise , the neck disability index questionnaire 
 ( ndi ) , a widely used questionnaire that determines how neck pain affects daily life17 , was also completed before and after 
 treatment .
electromyography ( telemyo 2400 t g2 , noraxon , usa ) measurements of the right - side 
 muscles known to have excessive fatigue and affect fhp ; i.e. , the upper trapezius , 
 sternocleidomastoid ( scm ) , and c4 paraspinals , were recorded at 1,500  hz before and after 
 the ten - week treatments10 , 18 . to obtain each muscle fatigue measurement , the reference 
 voluntary contraction ( rvc ) values for three seconds in the sitting position
the 
 median frequency ( mdf ) was calculated as an index of muscle fatigue , with lower median 
 frequency corresponding to increased muscle fatigue .
statistical analyses were performed 
 using pasw statistics for windows , version 18.0 , and p<0.05 were considered statistically 
 significant differences . to test for the homogeneity of each group , an independent t - test 
 was used before intervention . to verify the interaction between the groups and periods , we 
 used split - plot one - way repeated measures analysis of variance ( anova ) .
in addition , post 
 hoc tests were used to analyze the significant differences between each factor in the group 
 before and after intervention .
descriptive statistics for the two groups and the pre- and post - treatment measurements are 
 shown in table 2table 2.pre- and post - intervention outcome measures between pilates and control 
 groupsoutcome measures pilatescontrolprepostprepostcraniovertebral angle ( )65.6  4.570.1  4.8**69.1  2.469.1  3.2flexion rom ( )35.1  6.346.6  8.8**41.6  6.144.0  6.6extension rom ( )50.1  11.757.1  9.3 * 48.5  9.552.6  7.9right side flexion rom ( )29.5  3.134.0  3.8**29.6  4.130.9  4.5left side flexion rom ( )33.9  5.536.6  4.632.1  3.633.6  4.5right rotation rom ( )51.5  10.657.8  5.8 * 54.6  9.153.3  6.6left rotation rom ( )52.1  10.157.2  6.7 * 51.9  8.155.1  4.6vas pain scale5.9  1.62.5  1.5***5.4  1.72.7  1.8***neck disability index10.4 
3.55.1  2.1***10.7  3.25.9  3.4***emg data upper trapezius41.9  15.641.3  13.643.3  21.927.8  9.5emg data scm27.3 
11.343.5  17.29**49.2  17.645.2  19.0emg data cervical paraspinals34.9  13.342.5  20.239.9  19.338.8  25.1data are presented as means  sd .
* p<0.05 , * * p<0.01 , * * * p<0.001 between pre 
 and post measurement .. two participants in the pilates group dropped out for unknown reasons .
there were no statistical 
 differences between the pre - treatment descriptive characteristics and variables of the study 
 participants .
there was significant improvement in cva in the pilates group between the pre- 
 ( 65.65  4.53 ) and post - treatment ( 70.09  4.78 ) measurements ( p=0.002 ) .
however , there 
 was no significant improvement in the combined exercise group ( 69.08  2.40 , 69.13  
 3.19 ) . among cervical rom measurements ,
there were significant changes in flexion ( p=0.017 ) 
 and right rotation ( p=0.034 ) in the pilates group , but no significant differences in these 
 measurements in the combined exercise group .
similarly , there were significant improvements 
 in extension ( p=0.037 ) , right lateral flexion ( p=0.006 ) , right rotation ( p=0.045 ) , and left 
 rotation ( p=0.033 ) in the pilates group , but not in the combined exercise group .
pain decreased significantly in both the 
 pilates ( p<0.001 ) and combined exercise groups ( p<0.0001 ) after intervention . 

likewise , there were no significant changes between groups in ndi ( p<0.001 for both ) , 
 which decreased significantly after intervention .
the only significant difference between 
 the pilates and combined exercise groups in median emg frequency data was for the scm 
 ( p=0.026 ) .
* p<0.05 , * * p<0.01 , * * * p<0.001 between pre 
 and post measurement .
cva is commonly used as an indicator of fhp , which is due to muscle imbalance , related to 
 pain , fatigue , and limited motion of the cervical spine2 , 18 , 19 .
increased cva improves fhp , which suggests the potential to 
 mitigate the fhp problem . in this study ,
the pilates treatment program appeared to significantly improve 
 head posture in participants with fhp . in a similar study ,
emery et al.20 reported that a 12-week pilates training program 
 strengthened core muscles and improved thoracic kyphosis .
kuo and associates13 similarly illustrated that even a ten - week 
 pilates training program in individuals aged above 60  years could slightly reduce thoracic 
 kyphosis angle .
fhp in a 
 standing posture is linked with a lack of control of the abdominal muscles , which aggravates 
 thoracic kyphosis , making it more difficult to hold the head sufficiently high to maintain 
 normal eye level22 . based on the results 
 of these previous studies ,
therefore , it seems likely that pilates training , which helps spinal 
 realignment , may improve fhp .
the pilates program in this study focused on improving 
 systematic balances rather than specific ( cervical or thoracic ) regions , which emphasizes 
 core stability and spinal separation .
furthermore , the additional benefits of pilates 
 exercises include decreased hypertension in shortened and weakened muscles during 
 exercise7 ; improved breathing methods 
 ( diaphragmatic and rib breathing ) that improve core stability ; and increased awareness of 
 postural misalignments . the results of this study indicate that pilates training results in 
 whole - body muscle retraining , which strengthens the deep neck muscles to improve cva and 
 thus reduce neck pain .
in contrast , kuo et al.13 demonstrated that combined stretching and strengthening exercises 
 using a ball and foam roller improved fhp and round shoulder in eight weeks .
similarly , 
 harman et al.10 reported that ten weeks 
 of combined exercise improved fhp . in this study , all categories , except left - side flexion in the pilates group , showed 
 significant increase in the cervical rom .
although the results of the left - side flexion were 
 not statistically significant , they did show a slight increasing tendency .
the international headache society , defines headaches associated 
 with soft tissue or bone structures of the neck as cervicogenic headaches .
headache patients 
 with neck and shoulder pain can decrease their pain and increase cervical rom by practicing 
 pilates exercises .
it is unclear why only the pilates group experienced increased cervical 
 rom , as resistive exercises for spinal , scapular , and pelvic stability reportedly optimize 
 mechanical movement and increase rom23 .
we hypothesized that the results of the combined exercise group contradicts what we would 
 expect for the following reasons .
first , in our study , the combined exercise treatment used 
 a range of exercises that focused on correcting systematic muscle imbalances rather than 
 only focusing on the deep neck muscles , which reduced the amount of time devoted to the neck 
 muscles .
second , using resistance training may prove counterproductive in women with fhp due 
 to overwork of the structures of the weak and unstable cervical disks , creating more 
 movement dysfunction24 .
third , pain is 
 associated with altered muscle recruitment patterns ; thus , it may be useful to include 
 exercises that can retrain muscle recruitment patterns , especially ones that focus on the 
 theory of stabilizing locally before moving globally7 . furthermore , as pain increases , muscle guarding becomes pronounced , 
 leading to limited motion and constant muscle contraction .
this high level of muscle 
 contraction and tone shortens muscles and creates exaggerated muscle imbalances and thus 
 more pain24 .
future studies should 
 include treatments with specific phases to correct postural malalignments , such as an 
 initial phase focusing on correcting local malalignments , with a second phase focusing on 
 global malalignments , and finally a phase devoted to generalized strengthening and 
 flexibility .
the results of this study showed significant decreases in vas and ndi scores for the 
 pilates and combined exercise groups .
our study agrees other study findings4 that the cva is significantly lower in 
 groups with more self - reported neck pain .
in addition , sohn et al.5 reported that tension - type headaches become more common with 
 decreasing cva .
likewise , individuals with neck and shoulder pain tend to have higher 
 incidences of headaches5 . therefore ,
as 
 pilates exercise increases cva , its practice should results in a subsequent decrease in neck 
 and shoulder pain , which may inhibit potential headaches25,26,27 .
szeto et al.6 observed higher muscle 
 fatigue in the trapezius muscle in groups of people with fhp .
they also reported that 
 excessive computer use tends to exacerbate fhp . in this study
, the pilates group did not 
 have a significant reduction in upper trapezius muscle fatigue , but did show a significant 
 reduction in scm fatigue . on the contrary , the combined exercise program did not have 
 significantly reduced muscle fatigue , and had increased upper trapezius muscle fatigue . 

combined exercise while there is muscle tension around the neck and shoulders due to muscle 
 imbalance maybe counterproductive as other muscles are forced to compensate ; that is , become 
 overworked and fatigued . in conclusion , the results of this study indicate that the pilates program was more 
 effective in improving cva , cervical rom , and muscle fatigue than the combination of 
 stretching and resistance exercise .
pilates focuses on strengthening the core muscles , which 
 improves an individual s overall posture and postural awareness , which in turn increases 
 global and local stability .
therefore , pilates should be recommended as an appropriate 
 method for treatment and prevention of fhp .
 [ purpose ] this study compared the effects of pilates and an exercise program on the 
 craniovertebral angle , cervical range of motion , pain , and muscle fatigue in subjects with 
 a forward head posture ( fhp ) . [ subjects and methods ] a total of 28 sedentary females ( age 
 20 to 39  years ) with fhp were randomly assigned to pilates ( n=14 ) and combined ( n=14 ) 
 exercise groups . 
 the study was a randomized , controlled , double - blind study with the two 
 groups performing exercise 50  min / day , 3 days / week , with an intensity of 1115 rating of 
 perceived exertion ( rpe ) for ten weeks . 
 the main outcome measures were craniovertebral 
 angle , cervical range of motion ( rom ) , pain levels assessed by visual analog scale ( vas ) , 
 and neck disability index ( ndi ) . 
 surface electromyography was also used to measure muscle 
 fatigue . 
 [ results ] there were significant increases in craniovertebral angle and cervical 
 rom in the pilates group , but none in the control group . the only significant differences 
 in muscle activity were recorded in the sternocleidomastoid muscle in the pilates group . 
 
 both exercise programs had positive effects on pain measures , as vas and ndi were 
 significantly decreased . 
 [ conclusion ] the results suggest that pilates could be 
 recommended as an appropriate exercise for treatment of fhp in sedentary individuals . 
INTRODUCTION
SUBJECTS AND METHODS
RESULTS
DISCUSSION