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Journal of Bodywork & Movement Therapies (2013) xx, 1e8

Available online at www.sciencedirect.com

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EXERCISE PHYSIOLOGY

Antagonist coactivation of trunk stabilizer musclesduring Pilates exercises

Denise Martineli Rossi, PT, MSc a,*, Mary Hellen Morcelli, PT, MSc, Ph.D a,Nise Ribeiro Marques, PT, MSc, Ph.D a, Camilla Zamfolini Hallal, PT, MSc,Ph.D a, Mauro Goncalves, PT, Ph.D a, Dain P. LaRoche, BExSc, Ph.D b,Marcelo Tavella Navega, PT, Ph.D c

aDepartment of Physical Education, Sao Paulo State University, Rio Claro, BrazilbDepartment of Kinesiology, University of New Hampshire, Durham, NC, USAcDepartment of Physical Therapy and Occupational Therapy, Sao Paulo State University, Marılia, Brazil

Received 6 September 2012; received in revised form 9 April 2013; accepted 11 April 2013

KEYWORDSElectromyography;Stability;Pilates method;Physiotherapy

* Corresponding author. Tel.: þ55 19E-mail address: denisemartineli@h

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Summary The purpose of this study was to compare the antagonist coactivation of the localand global trunk muscles during mat-based exercises of Skilled Modern Pilates. Twelve womenperformed five exercises and concurrently, surface EMG from internal oblique (OI), multifidus(MU), rectus abdominis (RA) and iliocostalis lumborum (IL) muscles was recorded bilaterally.The percentage of antagonist coactivation between local (OI/MU) and global muscles (RA/IL)was calculated. Individuals new to the practice of these exercises showed differences in coac-tivation of the trunk muscles between the exercises and these results were not similar bilat-erally. Thus, in clinical practice, the therapist should be aware of factors such ascompensation and undesirable rotation movements of the trunk. Moreover, the coactivationof global muscles was higher bilaterally in all exercises analyzed. This suggests that the exer-cises of Skilled Modern Pilates only should be performed after appropriate learning and correctexecution of all principles, mainly the Centering Principle.ª 2013 Elsevier Ltd. All rights reserved.

3526 4345.otmail.com (D.M. Rossi).

ssi, D.M., et al., Antagonist coact(2013), http://dx.doi.org/10.101

3 Elsevier Ltd. All rights reserved3.04.006

Introduction

The Pilates Method is a kinesiotherapeutic techniquewidely used by therapists that was created during the FirstWorld War by Joseph Pilates. The prescription and compo-sition of the exercises was based on his experience with the

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.

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rehabilitation of injured people (Loss et al., 2010). Thismethod is based on six principles: concentration, control,flowing, precision, breathing and the centering principle,considered a differential technique of the method(Gladwell et al., 2006). The Centering Principle consists ofan isometric contraction of the internal oblique andtransverse abdominis muscles, which contributes toincreased antagonist coactivation of the deep lumbarmuscles (Marques et al., 2012).

Currently, the Pilates Method has been widely appliedin physiotherapy for flexibility training, stimulation ofblood circulation, improvement of postural alignmentand body awareness (Muscolino and Cipriani, 2004). Theexercises challenge the stability of the trunk and acti-vate the deep muscles of the lumbo-pelvic region (mul-tifidus, internal oblique and transversus abdominis), andrequire endurance of trunk muscles (rectus abdominis,iliocostalis lumborum and latissimus dorsi) (Endleman andCritchley, 2008). Thus, the Pilates Method has been usedfor both prevention and rehabilitation of low back pain(Muscolino and Cipriani, 2004; Endleman and Critchley,2008).

Low back pain is a common musculoskeletal symptom inmodern society that results in significant costs to health-care systems. It is estimated that 90% of cases of low backpain have a nonspecific origin, so this condition has amultifactorial and complex etiology (Ebenbichler et al.,2001). Among the possible causes of nonspecific low backpain are muscle dysfunctions, changes in motor control andinadequate recruitment of trunk muscles, which lead toreduced stability of the segments of the spine and altereddistribution of loads in this region (Ebenbichler et al.,2001).

Recently, Skilled Modern Pilates has been proposed as anadaptation of the traditional Pilates Method which has beenwidely applied in physiotherapy. This new approach to thePilates Method uses the philosophy created by JosephPilates, but decreases the range of motion of the exercisesand requires a neutral lumbar-pelvic posture (Latey, 2001,2002). Neutral lumbar-pelvic posture is more adapted tothe physiological curvature of the lumbar spine and alsoprovides an optimal position to increases the recruitment ofdeep lumbar and abdominal muscles (Sapsford et al., 2001;O’Sullivan et al., 2006).

According to O’Sullivan et al. (2006), in the lumbo-pelvicupright sitting posture, that is, neutral lordosis of thelumbar spine, the local muscles, multifidus and internalobliquus, had 62% and 30% higher activity (respectively)compared to an extended thoracolumbar spine posture,and 62% and 48% higher activity (respectively) compared toa relaxed thoracolumbar spine with a posteriorly rotatedpelvis. Additionally, spinal stability is increased with thecoactivation of the local trunk muscles and this strategypromotes protection of spine structures during the perfor-mance of functional activities (Arokoski et al., 2004). In thisregard, electromyography has proven to be an importanttool to study the function of the neuromuscular system ofthe low back by quantifying the coactivation of antagonistmuscle groups (Granata et al., 2005).

The stability of the segments of the spine is provided bythe interaction of three subsystems: active, composed byskeletal muscles surrounding the spine; passive, composed

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of vertebrae and their articular structures; and neural,composed of afferent, efferent, and central neural controlmechanisms (Panjabi, 1992). In physiological conditions,these subsystems provide spinal stability, principally, withthe recruitment of the trunk muscles, which provide dy-namic stability (Panjabi, 2003). Moreover, it is suggestedthat the most widely used mechanism for the maintenanceof spinal stability is the coactivation of trunk muscles, sincethis strategy promotes protection of spinal structures dur-ing the performance of functional activities. In this regard,electromyography has proven to be an important tool tostudy the function of the neuromuscular system of the lowback by quantifying the coactivation of antagonist musclegroups (Granata et al., 2005).

Studies of spinal stability point to structural differenti-ation of local and global trunk muscles based on their director indirect attachment to the vertebrae. The local muscles,such as multifidus (MU) and internal oblique (OI), despitehaving a limited capacity to generate torque, have in-sertions on the vertebrae, which contribute to control themovement of each lumbar vertebra. On the other hand, theglobal muscles, such as the rectus abdominis (RA) and theiliocostalis lumborum (IL), cross several joints with at-tachments to the pelvis and the thorax, have a largermoment arm, and are suited to the control of trunk orien-tation and the resistance of external forces (Bergmark,1989; Hodges, 2003).

In clinical practice, the largest recruitment of globalmuscles seems to be associated with an increase in spinalload that has the potential to cause injury or worsen pain inpatients with low back pain (Arokoski et al., 2004). Ac-cording to Arokoski et al. (2004) therapists should find morecautious exercises to challenge the local stabilizing musclesof the lumbar spine without placing an excessive load onthe structures of this region. Thus, considering the impor-tance of lumbopelvic and segmental spinal stability and therelationship to the trunk muscle response, the mat-basedSkilled Modern Pilates exercises can be an alternative toimprove conditioning and strength of trunk muscles withoutoverloading the passive structures of the spine (Arokoskiet al., 2004).

In addition to focusing on the activation of local mus-cles, the Skilled Modern Pilates exercises are performed ina neutral position that leads to greater local musclerecruitment than global recruitment (O’Sullivan et al.,2006). Also, these exercises can be considered functionalsince they require the recruitment and sensoriomotorcontrol of the trunk muscles while performing limb move-ments (Menacho et al., 2010).

To our knowledge, no study had investigated the dif-ferential activation of local and global trunk muscles dur-ing these exercises. Therefore, the purpose of this studywas to compare the antagonist coactivation of the localand global muscles during several mat-based Skilled Mod-ern Pilates exercises to ascertain which exercises stimulatelocal muscle coactivation most. From the principles ofPilates, we hypothesized that during the execution of theexercises in a neutral posture, the local muscle antagonistcoactivation would be higher than the global muscleantagonist coactivation to minimize the disturbance ofvertebral segments created by upper and lower limbmovements.

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Methods

Subjects

This cross-sectional study utilized twelve, young women,recruited from the university who were physically activewith no previous experience with Pilates exercise (Table 1).From a pilot study conducted in our laboratory, sample sizewas estimated by considering a standardized effect size of1.2 with alpha error of 0.05 to find differences in theactivation of local and global muscles bilaterally during theHundreds (level I) exercise. Subjects were excluded fororthopedic disorders, neurological problems, cardiovascu-lar disease, or previous surgery of the spine or abdomen.This study was approved by the Local Ethics committee(case number 067/2009), and all volunteers signed aninformed consent.

Procedures

Data collection was performed during two different ses-sions. On the first day, weight, height, body mass index, ageand physical activity level were recorded. Also, the volun-teers were familiarized with the Skilled Modern PilatesMethod principles and they practiced all the exercisesperformed during the data collection day using the sameprotocol. On the second day, the subjects performed asingle trial of each of the five exercises including, Hundredslevel I (HU I), Hundreds level II (HU II), One Leg Stretch levelI (OLS I), One Leg Stretch II (OLS II) and Scissors level I (SCI), in random order. All exercises were supervised by aphysiotherapist with experience in the Pilates Method.Concurrently, surface EMG from OI, MU, RA and IL wasrecorded bilaterally.

Exercises

The volunteers were taught to recruit their deep abdominalmuscles using a variety of strategies, including visual im-agery, verbal cueing and demonstration. Moreover theconscious recruitment of the deep abdominal muscles andthe incorporation of the Pilates principles of breathingcontrol and neutral spinal alignment were taught andencouraged during the exercises. The neutral position wasdefined as the intermediate position between lumbar spineretroversion and anteversion and was maintained andmonitored during the exercises by a barometric systemspecially developed for the study. This was a simple device

Table 1 Means of body anthropometrics, age and physicalactivity level of the subjects (n Z 12).

Mean (�SD)

Mass (kg) 56.74 (7.7)Height (m) 1.62 (0.06)Body mass index (kg$m2) 21.57 (2.3)Age (years) 20.05(2.5)Physical activity level (hours/week) 5.54 (1.91)

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composed of a bag that was inflated under the back ofthe volunteers which required them to maintain acertain pressure (and thus position), with a tolerance of�10 mmHg. The device was used to ensure quality andprecision in exercise performance by testing and moni-toring the position of the low back as a control for theevaluator and also to provide feedback to the subjectsabout the contraction of the abdominal muscles.

Prior to execution of the exercises, the subjects wereplaced in an initial position lying supine with their kneesflexed at 45�, feet aligned in the sagittal plane with theischial tuberosity, the lumbar spine in a neutral position,and the arms extended alongside the body. From thisstarting position, the five exercises were performed, HU I,HU II, OLS I, OLS II and SC I, during which the electromyo-graphic signal of the local and global muscles of the trunkwere recorded.

The HU I exercise was performed with the subjects in thesupine position, with the hips and knees flexed, while thefeet remained flat on the floor and the upper limbs wereheld alongside the body. Subjects were instructed toperform low amplitude shoulder flexion of both upper limbswith the hands held approximately 15 cm above the floor(Fig. 1A). The HU II exercise involved the same shoulderposition as HU I, but simultaneously required the subjectsto hold the dominant hip and knee flexed at 90� (Fig. 1B). Inthe OLS I exercise the subjects performed only lower-limbmovements. Starting from the initial flexed position withfeet on the ground, the subject performed controlled hipand knee extensions, lowering the leg until contact withthe ground, one leg at a time (Fig. 1C). In the OLS II exer-cise, the subjects started from the initial position with bothhips and knee flexed at 90� with the feet off the ground,and then the subjects unilaterally extended the knee andhip, while keeping the feet off the ground, returning to theinitial position, which was then repeated with the other leg(Fig. 1D). In the SC I exercise the subjects started with theknee and hip flexed at 90� bilaterally with both feet off theground. They then touched the toe to the ground, alter-nating feet, while keeping the contralateral lower limbsuspended (Fig. 1D).

Electromyography

The surface EMG signal was collected during the exercisesusing an eight-channel telemetry system (Noraxon�

Scottsdale, Arizona, USA) and was recorded with Myor-esearch software (Noraxon�), with a sampling frequency of2000 Hz and a total gain of 2000 times (20 times in thesensor and 100 times in the equipment). The signal wasrecorded using Ag/AgCl surface electrodes (Miotec�, PortoAlegre, Brazil), placed in bipolar configurations, with arecording area of 1 cm in diameter and interelectrodedistance of 2 cm. Prior to electrode placement, the skinwas carefully shaved and cleaned with alcohol to reduceresistance (Goncalves et al., 2012).

The electrodes were placed bilaterally on the muscles asfollows: OI, 2 cm medial and inferior to the superior ante-rior iliac spine; MU, 2 cm lateral to the midline of theinterspinous space L4-L5; RA, 3 cm above of the umbilicusand 2 cm lateral to the midline; IL, 6 cm lateral of theintervertebral space L2-L3. A reference electrode was

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Figure 1 A: Hundreds level I; B: Hundreds level II; C: One Leg Stretch level I; D: One Leg Stretch level II and E: Scissors level I.

Table 2 Repeated measures analysis of variance resultsfor comparison of local and global antagonist coactivation infive exercises analyzed for the right and left side.

Right Side Left Side

f P f p

ExercisesDof: 4

5. 145 0. 002* 1. 645 0. 180

Local/globalDof: 1

31. 966 0. 0001* 37. 336 0. 0001*

Exercises � local/global Dof: 4

0. 198 0. 624 0. 753 0. 753

*p < 0.05.

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positioned over the styloid process of the ulna on the rightarm (Hermens et al., 2000; Marshall and Murphy, 2003;Marques et al., 2012).

Data analysis

EMG signal analysis was carried out using specific routinesdeveloped in Matlab (Mathworks� Natick, USA). The EMGsignal was full-wave rectified and smoothed using a 4thorder low-pass filter with a cut off frequency of 10 Hz. Thelinear envelope EMG data from each muscle, of eachparticipant, was used to calculate the level of coactivation.For this analysis, the area under the signal amplitude curvewas determined for the OI, MU, RA and IL muscles and thepercentage of agonist/antagonist coactivation (% COCON)for the local muscles OI/MU and global muscles RA/IL wascalculated using the following equation (Candotti et al.,2009):

% COCONZ2� common area AB

area Aþ area B� 100

where % COCON is the percent coactivation between twoantagonist muscles, area A is the area below the smoothedEMG curve of muscle A, area B the area below the smoothedEMG curve of muscle B, common area A & B is the commonarea of activity of muscles A and B (Candotti et al., 2009).

Statistical analysis

The PASW 18.0 statistical package (SPSS Inc.) was used toperform the statistical analysis. Comparisons were madefor percentage coactivation between local and globalmuscles for the five exercises using repeated measuresanalysis of variance.

Comparisons were made between percentage coac-tivation between two local antagonist muscles (OI/MU) andtwo global antagonist muscles of the trunk (RA/IL) as forthe five exercises using repeated measures analysis ofvariance (ANOVA) for the right and left sides of the body

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separately. This resulted in a 2 (local vs. global) � 5 (ex-ercises) analysis for each side of the body. Post hoc testswere performed using the Least Significant Difference (LSD)statistic to show which exercise had higher antagonistcoactivation. Statistical significant was set at p < 0.05 forall tests.

Results

Table 2 describes the repeated measures ANOVA results ofthe %COCON of the local antagonist muscles (OI/MU) andglobal antagonist muscles (RA/IL) in the five exercisesanalyzed, for the right and left sides of the body. On theright side, there was a significant difference for the coac-tivation between the exercises (f Z 5.145 and P Z 0.002)and between the local and global antagonist coactivation(f Z 31.966 and P < 0.0001). On the left side, there was adifference only for the %COCON between local (OI/MU) andglobal (RA/IL) antagonist muscles (f Z 37.366 and P <0.001). For both sides, there was no significant differencein the interaction of exercise and antagonist coactivation.

For the right side, global %COCON (RA/IL) was 52.01%higher than local %COCON (IO/MU) (Fig. 2a) and for the left

ivation of trunk stabilizer muscles during Pilates exercises, Journal6/j.jbmt.2013.04.006

Figure 2 (a) Comparison of the local and global %COCON on the right side; (b) Comparison of the local and global %COCON on theleft side. y Z significant difference between global (RA/IL) and local (IO/MU) %COCON.

Antagonist coactivation of trunk stabilizer muscles during Pilates exercises 5

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side global %COCON was 45.46% higher than local %COCON(Fig. 2b). Additionally, HU I exercise had 19.99% and 22.32%higher coactivation than OLS I (p Z 0.057) and SC I(p Z 0.013); and HU II had 19.45%, 15.47% and 21.87%higher coactivation than OLS I (p Z 0.032); OLS II(p Z 0.058) and SC I (p Z 0.011; Fig. 3).

Discussion

Due to the significance of the Pilates Method to the clinicalpopulation with low back pain, is important to study theantagonist coactivation of the trunk muscles, particularlywith respect to the potential vertebral overload duringthese exercises. Activation of trunk muscles has beendescribed as one of the mechanisms used to maintain spinalstability and provide protection to structures. This is

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particularly the case for the local spinal muscles used tominimize the disturbance of the vertebral segmentscreated by movements of the upper and lower limbs(Granata et al., 2005). From the principles of the PilatesMethod, which aim to activate the deep muscles of thelumbo-pelvic region, the initial hypothesis of this study wasthat during the exercises in neutral lumbar spinal align-ment, the antagonist coactivation of the local muscleswould be higher compared to global muscles.

In this study, the comparison of antagonist coactivationof the trunk muscles during mat-based Skilled ModernPilates exercises demonstrated that for the right side, theHU I and HU II exercises had higher antagonist coactivation.In contrast to our findings, Souza et al. (2001) found nodifference in EMG activity between the right and left sidesduring the execution of exercises for spinal segmentalstabilization. Our results may be related to possible

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Figure 3 Comparison of the coactivation between the exercises on the right side. * Z significant difference between HUI Z Hundreds level I and OLS I Z One Leg Stretch level I; £ Z significant difference between HU I and SC I Z Scissors level I;x Z significant difference between HU II Z Hundreds level II and OLS I; U Z significant difference between HU II and OLS II Z OneLeg Stretch level II; z Z significant difference between HU II and SC I Z Scissors level I.

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compensation in the trunk muscle activation to maintainstability during the execution of the exercises. The asym-metry of the load application from the weight of the lowerlimbs during the execution of the unilateral exercisesgenerates disturbance and trunk rotation which may haveled to higher coactivation of trunk musculature on the rightside. Also, the fact that all the subjects of the sample wereright-handed should also be considered.

When investigating the EMG coactivation of the global andlocal trunk muscles, in contrast to the initial hypothesis, thisstudy found that on both sides of the body, antagonistcoactivation of the globalmuscles, RA and IL,was higher in allexercises. The anterior and posterior muscles of the trunk,like RA and IL, play important roles in maintaining the sta-bility of the vertebral column. Because they are consideredhistological and anatomically as global muscles, they arefunctionally responsible for generating the torque requiredto move the trunk and limbs and to transfer the externalloads to minimize overload of the spine (Hodges, 2003).

During the execution of OLS level I and II and SC level Iexercises, alternating movements of the lower limbs inboth closed kinetic chain (OLS I) and open kinetic chain(OLS II and SC I) exercises were performed. There is arelationship between increased antagonist coactivation ofthe trunk muscles, the asymmetric load applied, and thelength of the lever arm (McCook et al., 2009). The localmuscles, MU and OI, act to “fine tune” intervetebralmovements and generate shear forces during changes in theposition of the trunk. The global muscles, RA and IL, arefundamental to pelvic stability during exercises with kneeextension and also work to control the torque generatedby hip extension (Hodges, 2003). Thus, it can be inferredthat besides the need to maintain spinal stability and theneutral position of the lumbar spine, the highest globalantagonist coactivation of the trunk muscles was necessaryfor the production of flexor torque as a result of dynamicalternation of leg movements and the long lever arm of thelower limb (Hodges, 2003; McCook et al., 2009).

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The control of joint and spinal stability depends directlyon the active system coordinated by the contraction ofmuscles. The stability of the system is provided by thenecessary stiffness to appropriately restrict movement. Inthe spine, the compressive forces caused by the tension ofpassive structures and muscle action in the joints providestiffness and stability. The stabilization of the lumbar spineis significantly increased by the tension applied by the localand global muscles in the thoracolumbar fascia (Van dieenet al., 2003a, b; Reeves et al., 2007). According to Vandieen et al. (2003a,b) the direction of the external pertur-bation forces is the main factor that will determine whichtrunk muscles are recruited to stabilize the spine. Further-more, despite histological, anatomical, and functional dif-ferences, the stability of the column is provided by all thetrunk muscles. Thus, the system continuously adjusts thestiffness of the column to generate the stability required ofcertain tasks, and the force and movement characteristicsof the task determine which muscles are more active (Vandieen et al., 2003a, b, Reeves et al., 2007).

Pilates exercises are used for spinal stabilization andhave been widely used to treat low back pain (Arokoskiet al., 2004). It has been shown that the maintenance ofpostural alignment during the exercises stimulates theactivation of stabilizing muscles, such as the internal obli-que, transversus abdominis and multifidus muscles (Coladoet al., 2011). In the initial phase of rehabilitation,contemporary approaches involve the recruitment ofabdominal muscles such as transversus abdominis (TrA) andOI, with minimal activity of the superficial abdominalmuscles. These practices are based on evidence that in-dividuals with low back pain have dysfunction of thesemuscles and exercises that aim to improve the recruitmentof these muscles will contribute to vertebral control.Furthermore, these treatments focus on low-levelcontraction, as it has been suggested that low levels ofcontraction are sufficient to provide the stiffness requiredfor control of the intervertebral joints (Urquhart et al.,

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2005). However, despite the known beneficial effects ofthese exercises, such as reduced intensity of pain anddysfunction, there is insufficient scientific and clinical ev-idence of how the actions of the muscles stabilizing thespine change during the execution of the exercises(Arokoski et al., 2004; Critchley et al., 2011).

This study examined a sample that did not report backpain, however, there is evidence that exercise therapyproduces lower activity of trunk muscles in subjects withlow back pain compared with subjects who never had aprevious painful episode (Arokoski et al., 2004). In clinicalpractice, the increased recruitment of global musclesseems to be associated with increased spinal load that cancause injury or worsen the pain in individuals with low backpain (Arokoski et al., 2004). Although the recruitment oflocal muscles is emphasized in the initial phase of reha-bilitation, all the muscles of the trunk are consideredimportant for the restoration of normal function and theprogression of exercises involves strategies for the reha-bilitation of the muscular system of the trunk as a whole(Arokoski et al., 2004; Urquhart et al., 2005).

Conclusion

Individuals new to the practice of the mat-based SkilledModern Pilates exercises showed differences in coactivationof the trunk muscles between the exercises. These resultsweren’t similar between the sides of the body, because foronly the right side, the HU I and HU II exercises had higherantagonist coactivation. Therefore, in clinical practice, thephysiotherapist should be aware of factors such ascompensation for weak muscles by one side of the bodythat may result in undesirable rotation movements of thetrunk. Furthermore, the antagonist coactivation of globalmuscles was higher than local muscles in all of the exercisesand it seems that this is associated with increased spinalload. Thus, these exercises should be performed afterappropriate learning of the movements and correctexecution of the Pilates principles, mainly the CenteringPrinciple, which is to activate the local stabilizing musclesto avoid overloading the spine.

Limitations

A limitation of this study is that the protocol was performedin a single attempt and results may have differed if theexercises were performed on separate days. Additional in-formation of how muscle activation is controlled during theexercises could have been made if the activity of othermuscles had been studied, such as the external obliquesand stabilizers of the hip. LSD post hoc tests were used toincrease the statistical power due a relatively small samplesize. Therefore, these initial findings should be interpretedcautiously and the study should be replicated. Anotherstudy limitation is that the volunteers were novices and hadno experience with the Pilates Method, and the muscleactivation response may be different in those familiar withthe exercises. Additional research should be conducted tostudy the activation of trunk muscles in people whoroutinely perform Pilates exercises to understand the ef-fect of training on trunk stabilizer muscle activation.

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Conflict of interest statement

None.

Acknowledgements

D.M. Rossi was supported by Coordenacao de Aperfeicoa-mento de Pessoal de Nıvel Superior (CAPES).

References

Arokoski, J.P., Valta, T., Kankaanpa, M., Airaksinen, O., 2004.Activation of lumbar paraspinal iand abdominal muscles duringtherapeutic exercises in chronic low back pain patients.Archives of Physical Medicine and Rehabilitation 85, 823e832.

Bergmark, A., 1989. Stability of the lumbar spine: a study in me-chanical engineering. Acta Orthopaedica Scandinavica 60, 4e54.

Candotti, C.T., Loss, J.F., Bagatini, D., Soares, D.P., Rocha, E.K.,Oliveira, A.R., Guimaraes, A.C.S., 2009. Cocontraction and econ-omy of triathletes and cyclists at different cadences during cyclingmotion. Journal of Electromyography and Kinesiology 19, 915e921.

Colado, J.C., Pablos, C., Chulvi-Medrano, I., Garcia-Masso, X.,Flandez, J., Behm, D.G., 2011. The progression of paraspinalmuscle recruitment intensity in localized and global strengthtraining exercises is not based on instability alone. Archives ofPhysical Medicine and Rehabilitation 92, 1875e1883.

Critchley, D.J., Pierson, Z., Battersby, G., 2011. Effect of thePilates mat exercises and conventional exercise programmes ontransverses abdominis and obliquus internus abdominis activity:pilot randomized trial. Manual Therapy 16, 183e189.

Ebenbichler, G.R., Oddsson, L.I., Kollmitzer, J., Erim, Z., 2001.Sensory-motor control of the lower back implications for reha-bilitation. Medicine and Science in Sports and Exercise 33 (11),1889e1898.

Endleman, I., Critchley, D.J., 2008. Transversus abdominis andobliquus internus activity during Pilates exercises: measure-ment with ultrasound scanning. Archives of Physical Medicineand Rehabilitation 89, 2205e2212.

Gladwell, V., Head, S., Haggar, M., Beneke, R., 2006. Does a pro-gram of the Pilates improve chronic non-specific low back pain?Journal Sport Rehabilitation 15, 338e350.

Goncalves, M., Marques, N.R., Hallal, C.Z., Van Dieen, J.H., 2012.Electromyographic activity of trunk muscles during exerciseswith flexible and non-flexible poles. Journal of Back andMusculoskeletal Rehabilitation 24, 209e214.

Granata, K., Lee, P.E., Franklin, T.C., 2005. Co-contractionrecruitment and spinal load during isometric trunk flexion andextension. Clinical Biomechanics 20 (10), 1029e1037.

Hermens, J.H., Freriks, B., Disselhorst-Klug, C., Rau, G., 2000.Development of recommendations for SEMG sensors and sensorplacement procedures. Journal of Electromyography and Kine-siology 10, 361e374.

Hodges, P.W., 2003. Core stability exercise in chronic low backpain. Orthopedic Clinics of North America 34, 245e254.

Latey, P., 2002. Updating the principles of the Pilates Method: part2. Journal of Bodywork Movement Therapies 6 (2), 94e101.

Latey, P., 2001. The Pilates Method: history and philosophy. Journalof Bodywork and Movement Therapies 5 (4), 275e282.

Loss, J.F., Melo, M.O., Rosa, C.H., Santos, A.B., La Torre, M.,Silva, Y.O., 2010. Eletrical activity of external oblique and mul-tifidusmuscles during hip flexion-extension exercise performed inthe Cadillac with different adjustments of springs and individualpositions. Revista Brasileira de Fisioterapia 14 (6), 510e517.

Marques, N.R., Morcelli, M.H., Hallal, N.R., Goncalves, M., 2012.EMG activity of trunk stabilizer muscles during Centering

ivation of trunk stabilizer muscles during Pilates exercises, Journal6/j.jbmt.2013.04.006

8 D.M. Rossi et al.

+ MODEL

Principle of Pilates Method. Journal of Bodywork and Move-ments Therapies, Impress.

Marshall, P., Murphy, B., 2003. The validity and reliability of sur-face EMG to assess the neuromuscular response of the abdom-inal muscles to rapid limb movement. Journal ofElectromyography and Kinesiology 13, 477e489.

McCook, D.T., Vicenzino, B., Hodges, P.W., 2009. Activity of deepabdominal muscles increases during submaximal flexion andextension efforts but antagonist co-contraction remains unchanged.Journal of Electromyography and Kinesiology 19, 754e762.

Menacho, M.O., Obara, K., Conceicao, J., Chitolina, M.L.,Krantz, D.R., Silva, R.A., Cardoso, J.R., 2010. Electromyo-graphic effect of mat Pilates exercise on the muscle activity ofthe healthy adult females. Journal of Manipulative and Physi-ological Therapeutics 33 (9), 672e678.

Muscolino, J.E., Cipriani, S., 2004. Pilates and the powerhouse-II.Journal of Bodywork and Movement Therapies 8, 122e130.

O’Sullivan, P., Dankaerts, W., Burnett, A.F., Farrel, G.T.,Jefford, E., Naylor, C.S., 2006. Effect of different upright pos-tures on spinal-pelvic curvature and trunk muscle activation in apain free population. Spine 31 (19), E707eE712.

Panjabi, M.M., 1992. The stabilizing of the spine. Part I. Function,dysfunction, adaptation and enhancement. Journal of SpinalDisorders 5 (4), 383e389.

Please cite this article in press as: Rossi, D.M., et al., Antagonist coactof Bodywork & Movement Therapies (2013), http://dx.doi.org/10.101

Panjabi, M.M., 2003. Clinial spinal instability and low backpain. Journal of Electromyography and Kinesiology 13,371e379.

Reeves, N.P., Narendra, K.S., Cholewicki, J., 2007. Spine stability:six blind men 493 and the elephant. Clinical Biomechanics 22,266e274.

Sapsford, R.R., Hodges, P.W., Richardson, C.A., Cooper, D.H.,Markewell, S.J., Jull, G.A., 2001. Co-activation of the abdom-inal and pelvic floor muscles during voluntary exercises.Neurology & Urodynamics 20 (1), 31e42.

Souza, G.M., Baker, L.L., Powers, C.M., 2001. Eletromyographicactivity of selected trunk muscles during dynamic spine stabi-lization exercises. Archives of Physical Medicine and Rehabili-tation 82, 86e92.

Urquhart, D.M., Hodges, P.W., Allen, T.J., Story, I.H., 2005.Abdominal muscle recruitment during a range of voluntary ex-ercises. Manual Therapy 10, 144e153.

Van dieen, J., Kingma, I., Van Der Gub, J.C.E., 2003a. Evidencefor a role of antagonistic cocontraction in controlling trunkstiffness during lifting. Journal of Biomechanics 36,1829e1836.

Van dieen, J.H., Cholewicki, J., Radebold, A., 2003b. Trunk musclerecruitment patterns in patients with low back enhance thestability of lumbar spine. Spine 28, 834e841.

ivation of trunk stabilizer muscles during Pilates exercises, Journal6/j.jbmt.2013.04.006