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Anterior and Posterior Serape

ARTICLE in STRENGTH AND CONDITIONING JOURNAL OCTOBER 2015

Impact Factor: 0.6 DOI: 10.1519/SSC.0000000000000162

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Stuart M Mcgill

University of Waterloo

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Lee E Brown

California State University, Fullerton

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Available from: Lee E BrownRetrieved on: 28 February 2016
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Anterior and Posterior

Serape: The RotationalCoreJuan C. Santana, MEd, CSCS*D, FNSCA,1 Stuart M. McGill, PhD,2 and Lee E. Brown, EdD, CSCS*D, FNSCA31Institute of Human Performance, Boca Raton, Florida; 2University of Waterloo, Waterloo, Ontario, Canada; and3Department of Kinesiology, California State University, Fullerton, California

A B S T R A C T

THE PURPOSE OF THIS ARTICLE IS

TO EXPAND A CONCEPT SUR-

ROUNDING THE ROTATIONAL

FUNCTION AND TRAINING OF THE

BODYS CORE. MORE THAN A

DECADE AGO, A MODEL WAS

PROVIDED BY WHICH TO

OBSERVE AND TRAIN THE CORE,

WHICH WAS BASED ON A PREVI-

OUSLY PUBLISHED THEORY

REGARDING THE SERAPE EFFECT.

THE PURPOSE OF THIS ARTICLE IS

TO EXPAND ON THAT MODEL, THE

ORIGINAL SERAPE EFFECT, AND

TO PROVIDE A MORE COMPLETE

MODEL FOR ANALYSIS AND

TRAINING OF THE BODYS CORE.

INTRODUCTION

The core of the body has beenthe topic of much discussionand debate over the past few

decades. Researchers and therapistshave postulated various theories onthe function of the core and variousways to train. Some groups theo-rized the importance of singlemuscles in stabilizing the spine forpain control such as the transverseabdominis (TVA) (5,6) and psoasfor walking and lifting patterns (4).Subsequently, some clinicians andeducators promoted specific core-training methods, such as the draw-ing-in maneuver and the activationof the TVA muscle. While these were

controversial, a broad discussion of

the appropriateness and efficacy of

these approaches is contained inMcGill (11). Others have addressedissues pertaining to training the corein a variety of ways, using unstablesurfaces being 1 example (1), tobroader ground-based approachesto training (15). The purpose of thisarticle is to consider the core ina broader functional sense in the con-text of rotational movement and tor-que production.

Given that the core has been the

topic of much discussion and debateover the past few decades, we beginwith a definition of where the corestops and where it starts. For the pur-pose of this article, we will considerthe core in 2 parts. First, the torsobetween the ball and socket jointsof the shoulders and hips forms whatis thought of traditionally as the core.The muscles that attach the pelvis,spine, and ribcage perform manyfunctions but for this first level ofdiscussion are generally responsible

to stop motion. The second part ofthe core enhances function withmuscles that cross the shouldersand hips to the upper and lowerlimbs. Because of its size and capac-ity to become rigid, the core serves asan anchor of sorts for the limbsespecially the upper extremities. Inmost athletic situations, the hip mus-culature generates the majority ofpower (2,7,12). The power is trans-ferred upward through the linkage to

the arms through a stiffened core

(2,7,12). Stiffness is the essential pre-

cursor to stability and the efficienttransfer of forces, together withbeing one of the keys to injury pre-vention (Myers (13) summarizes sev-eral studies that integrate theseconcepts together with quantifica-tion of stability). McGill (10,12) pre-sented 4 basic principles of spinal stability that may direct pur-poseful training, enhance perfor-mance, and help prevent a host ofinjuries related to instability: (a)proximal stiffness (meaning the lum-bar spine and core) enhances distalsegment athleticism and limb speed;(b) a muscular guy wire system isessential for the flexible spine tosuccessfully bear load; (c) muscularcoactivation creates stiffness to elim-inate micromovements in the jointsthat lead to pain and tissue degener-ation; and (d) abdominal armor isnecessary for some occupational,combative, and impact athletes.The serape (8) involves these fea-

tures from both ends of the core ina spiral pattern.

How does core stiffness enhancelimb speed and strength? Consideran example with a basic athleticmovement, throwing (Figure 1). Aright-handed pitcher winds upthe throw bringing the left leg upand balancing on the right leg,

K E Y W O R D S :

strength; power; core; training

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slightly flexing the right hip andknee. This position loads the poste-rior serape (i.e., posterior diagonalmusculature from right foot to leftshoulder) (Figure 1A). The pitcherstrides to begin the cocking phaseusing the posterior serape to gener-ate the forward momentum of thecorethis forward movement setsup the early cocking phase of thethrow. During the early cockingphase (Figure 1B), the anteriorserape (i.e., anterior diagonal muscu-lature from right arm to left foot) is

loaded, as the right arm and left legare extended and abducted. Duringthe late cocking phase, the left footis planted into the ground to decel-erate the left hips forward momen-tum, whereas the right hip continuesits forward movement. This footplant also loads the elastic compo-nent of the linkage to store someelastic energy. The counterclockwisehip rotation of the cocking phase(Figure 1C) sets up the accelera-tion phase to unleash the storedenergy. The key to the acceleration

phase is a stiff core so that maximumpower can be transferred betweenthe hips and the shoulders. However,the core stiffness is tuned with

the appropriate muscle activityto best enhance the storage andrecovery of elastic energy similar toan elastic band. Using the anteriorserape (i.e., right shoulder to lefthip), the cores bigger mass pullson the l ighte r r ight a rm of thepitcher, much like a hand pulls ona whip. Hip rotation is acceleratedin a counterclockwise direction bythe extension of the left leg (i.e., driv-ing the left hip back) as the right hipcontinues its forward trajectory

(Figure 1D). The acceleration phaseis complete as the ball is released andthe follow through phase begins(Figure 1E). The follow throughphase is decelerated by the posteriorserape that goes from the left gas-trocnemius muscle to the rightlatissimus.

Thus, the muscles create force andtuned stiffness. This tuning inessence allows active muscle forcesto work with the elastic recoil of other

tissues (e.g., ligament, tendons, andfascia). The muscles of the shoulders,hips, and limbs are generating forcesto create the motion in a pulsedsequence. The core is creating a stiff-ened anchor (proximal stiffness) tounleash this distal athleticism. Duringthe cocking and acceleration phases,the great athletes are better able totune the stiffness of the core muscu-lature to optimize the serapes whip(Figure 1).

The architecture of the serape is the

key. By creating a stiffened core ina spiral pattern, the proximal endsof the hip and shoulder muscles areanchored producing faster armand leg motion across the body. Thisis an essential component for allrapid reciprocal motion, such asrunning (particularly sprinting),throwing, kicking, changing direc-tion, sta ir c limbing, choppingfirewood, and even single-sided lift-ing and carrying. Thus, a universal

law of human movement is

Figure 1. Notice that there is little twisting of the core during the entire pitchingmotion beginning at wind up; the core is actually stiffened during thecocking and acceleration phases. This stiffening allows the serape muscleand other tissues to transfer the serapes hip power to the shoulders and

eventually the hand all the way to the follow through.

Figure 2. Logan and McKinneys (8) original serape looks like a giant scarf wrappedaround the back of the neck, crosses the front of the body, and tucks into

the pant line.

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establishedproximal stiffness en-hances distal mobility and athleticism(12). This requires core stiffnessenhanced by the serape.

Creating rotational power in the torsosection of the core is problematicfor enhancing performance whileimproving injury prevention. Power

is the product of force multiplied byvelocity, or in a rotational sense, twistvelocity multiplied by twisting torque.One of these must be low if the other

is high. For example, in the golf swing,the twist velocity is high, but the rota-tional force is low resulting in lowpower, and low risk. If the twist forceis high, then the speed must be low.This same concept holds true forpitching in baseballobserve themotion at the hips and shoulders asthere is very little torso twisting. How-ever, if the rotational force is high,then the twisting velocity must below to keep the torso power low.The implications for training are to

stiffen the torso and focus the twistmotion about the hips and shoulders.Consider exercises, such as the Paloffpress, birddogs, short cable/band ro-tations, one-arm push-ups, and one-arm standing cable pressesall ofthese are designed to enhance perfor-mance of the serape with minimal risk.For example, a staggered stance (leftfoot forward), contralateral-arm, bandor cable press, involves the diagonalcore musculature consisting of theright serratus anterior, the rightexternal obliques, left internal obli-ques, and the left hip flexor/adductorcomplex (1517).

Various functions, such as swinginga bat, use gravity to passively loadthe various systems of the body,together with active muscle forceincreasing and directing groundreaction forces to turn the hips,a stiffening of the core to connectthe hips to the shoulde rs a ndproduce rotation, the upper extrem-

ities then transfer the rotationalpower to the bat. This rotationalpower is a common theme through-out many of the bodys most cele-brated and used functions, fromswinging implements to running.The original serape effect presen-ted by Logan and McKinney (8) pro-vides some insight into the force-generation patterns used by thebody to transfer forc es a crossthe core. However, Logan and

McKinney clearly indicate that

Figure 3. The anterior and posterior oblique systems popularized by the physicaltherapy profession.

Figure 4. Vleemings (17) work on the anterior and posterior oblique sling systemclearly provides an insight as to how forces cross the pelvic junction in front

and behind the body.


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their serape effect is only part ofa multisystem model and it is thismultisystem model this article will

present.

Logan and McKinneys originalserape looks like a giant scarf wrappedaround the back of the neck, crosses

the front of the body, and tucks into

the pant line (Figure 2). This modelprovides graphic insight into the spiralnature of the bodys core, more spe-cifically, the diagonal nature of the

anterior accelerators.Introductory anatomy courses usuallydescribe the anterior and posterioroblique systems (Figure 3). In 10years of investigation and countlesscommunication with core/spineexperts, such as Vleeming (17,18),Myers (13,14), and others, we havenot been able to ascertain the originsor source of the anterior and posterioroblique system. However, the originof the oblique system may be tracedto the early 1900s, and the work ofLovett (9), and Dart (3) who intro-duced the concept of a spiralingmovement system governed by mus-cle and joint actions (3). In the mid1900s, Voss et al (19) also mention theoblique system and the pivot points,referring to them as patterns offacilitation.

Regardless of the origin of the ante-rior and posterior oblique musclesystems, Vleemings (17) work onthe anterior and posterior oblique

sling system clearly provides aninsight as to how forces cross thepelvic junction in front and behindthe body (Figure 4).

What is clear from the anatomicaldescription of the serape is that theinvolved muscles are arranged inseries fashion along spiraling lines.Myers (13) describes the myofascialconnections between these musclesand their tendons. Many of thesemuscles and tendons do not

connect directly to bone, rather theyconnect to one another transmittingforce along pathways rangingmuch further than simply the lengthof any one muscle (Figure 5). How-ever, to transmit force along theserape, muscle pairings emerge. Forexample, according to the posterioroblique model, the right glutealmuscles would pair with the left lat-issimus dorsi.

The anterior and posterior serape

(APS) is a concept to explain the

Figure 5. The serape involves muscles arranged in series fashion along spiraling lineswith myofascial connections between the muscles and their tendons.Many of these muscles and tendons do not connect directly to bone,rather they connect to one another transmitting force along pathwaysranging much further than simply the length of any 1 muscle.

Figure 6. The anterior serape looks like a ribbon wrapped around the back andcrossed in the front of the body, illustrating the bodys ability to function as

a bow using the anterior core musculature.



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total body routing of power inhuman movement (Figures 6 and 7).This model expands the originalserape spiral concept to include theupper and lower body on both sides.The diagonal ribbon crosses theupper body anteriorly through thepectorals and posteriorly throughthe rhomboids.

The APS model can provide a practi-tioner with an easy method to followthe force-generation patterns thebody uses to perform just about anyactivity, from running to throwinga ball, to picking up a barbell (e.g.,deadlift). The batting motion is usedto illustrate how the body works withthe APS (Figure 8).

A left-handed batter will load up theback swing on his left leg, while rotat-ing his shoulders to the left. This loadsup the posterior serape active muscu-

lature and related passive fascia fromthe left leg to the right shoulder: Left gastrocnemius/soleus. Left hamstring. Left gluteals and hip abductors. Right latissimus.As the posterior serape fires fromlower left to upper right, it loads theanterior serape from lower right toupper left, loading the following: Right hip flexors. Right adductors. Right internal oblique.

Left external oblique. Left serratus anterior.Once the above-mentioned APSmuscles (and related fascia) completethe contact phase, the opposite APSmuscles decelerate the swing, using thefollowing muscles (and related fascia):

Posterior serape: Right gastrocnemius/soleus. Right hamstring. Right gluteals. Left latissimus.Anterior serape: Left hip flexors. Left adductors. Left internal oblique.

Figure 7. The posterior serape looks like a ribbon wrapped around the front andcrossed behind the body, illustrating the bodys ability to function as a bowusing the posterior core musculature.

Figure 8. A left-handed batter will load up the backswing on his left leg, while rotating his shoulders to the left. This loads up theposterior serape musculature from the left leg to the right shoulder. As the posterior serape fires from lower left toupper right, it loads the anterior serape from lower right to upper left. Once the anterior serape completes the contact

phase, the opposite posterior serape decelerates the swing.


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Right external oblique. Right serratus anterior.The interplay of these diagonal pat-terns of muscular contractions pro-

vides the rotational power we seein many sports and functional activ-ities, such as running, golfing, kick-ing, and changes in direction. Evenwhat seem to be vertical activities,such as getting up out of a chair,throwing a soccer ball overhead, ver-tical jumping, piking during a dive,and deadlifting a bar, use the APS.During vertical activities such asthese, both diagonal patterns of theAPS are synchronously coordinated,so there is no net rotation when both

sides of the torso and legs produceforce, in essence creating whatMcGill (12) refers to as a super stiffcore. If all of the muscles of the ante-rior serape simultaneously contract,activities such as throwing a soccerball or performing a pike-tuck in div-ing become possible. Conversely, ifall of the muscles of the posteriorserape simultaneously contract,deadlifting a bar or performing a ver-tical jump is enabled.

CONCLUSIONS

The APS system unifies an under-standing of how the body organizesthe many parts of the body linkage tocreate rotational activity. Muscles ofthe serape form a spiraling system,augmented with elastic passive tissuessuch as fascia that enhances the effi-ciency of cyclic activity such as walk-ing, together with power and speedactivities such as throwing and golf.The stiffened core enables power pro-

duced distal and beyond the ball andsocket joints to transmit to the ball andsocket joint at the other end of thecore forming a whip. While this articleserved to form a foundation of definingand describing the serape or rotationalcore, a companion article suggests sev-eral techniques to enhance athleticperformance taking advantage ofthe APS.

Conflicts of Interest and Source of Funding:The authors report no conflicts of interest

and no source of funding.

Juan C.Santanais thePresident of theInstitute of

HumanPerformance.

Stuart M.McGill is a Pro-

fessor at theUniversity of Waterloo.

Lee E. Brown isa Professor atCalifornia StateUniversity.

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Anterior and Posterior Serape the Rotational.2