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PULLING MOVEMENTS Shoulder Or Elbow First?
Mark McKean (PhD Candidate)University of Sunshine Coast
Current Industry Issues
Scapula positioning and setting Scapula plane or coronal plane Should pulling movement be taught
as two actions or one? What should the range of movement
should the pull involve? Shoulder stability Push - pull Ratios? Structural balance of the shoulder?
Research Review
Scapula position/stability Shoulder strength ratios Scapula plane or coronal plane Other notes
Scapula Position/Stability
Trapezius and serratus anterior most important stabilisers acting on scapula thoracic joint (Mottram)
Deltoids generate significant shear force and compressive force in support of anterior shoulder instability.
The deltoid provides dynamic stability with the arm in the scapular plane and only decreased the stability of the shoulder with the arm in the coronal plane. (Lee & An)
Scapula stability exercises and thoracic curve correction should be done before rotator cuff exercises (Kibler)
Ideal scapula position yet to be determined but it is not in its inner range of lower traps, and “down and back” is not an appropriate command(Mottram)
Shoulder Strength Ratios
Suggested ratio of external to internal strength is approx 2/3.
Weight training more likely to cause imbalances (Kobler)
Rugby players – bench press to pull ups 1:1 (Baker)
Kayak paddlers – bench press to pull ups 1:1.47 (McKean - unpublished)
Relative height of the handle influences strength of push pull outcome and ratio (Badi & Boushaala)
Shoulder Structural Balance Deltoid : External Rotators : Lower
Traps 3 : 1.5 : 1 ratio of strength
Compared to 1RM Pull up (kayakers - Mckean unpublished data)
Deltoid – 18% External rotators – 9% Lower Traps – 6%
Scapula Plane or Coronal Plane
Internal rotator strength similar for both planes but external rotator strength better in scapula plane (Greenfield et al)
Horizontal muscle force was decreased 16.2% in the slouched thoracic position for abduction to horizontal in scapula plane. (Kebaetse et al)
Glenohumeral – Scapulothoracic Rhythm
The scapulo-humeral rhythm (2.2–2.5) and scapular tilting (2–4°) remained relatively constant during elevation (Graichen et al)
Mean ratio of gleno-humeral to scapulo-thoracic motion was 1.7:1
Normal scapular motion consists of substantial rotations around 3 axes
Significant relationship in scapula-thoracic-humeral-clavicle movement (McClure et al)
Clavicular and scapular angles were significantly related to the arm elevation (de groot)
Other Notes
Although movement analysis is considered an integral part of a physiotherapist's skill, research has shown that a sample of experienced manipulative physiotherapists had difficulty in determining the symptomatic status of patients with clinically diagnosed shoulder complaints by movement analysis alone. 58% accuracy achieved (Hickey et al)
Push pull movements/stabilising showed postural adjustments were initiated shortly before all focal movements (Cordo & Nashner)
Research Summary
Scapula neutral position requires muscular support and correct thoracic curve
Shoulder strength ratios exist but may be sport or activity specific
All rotator cuff strength most balanced in scapula plane
Scapula, thoracic spine and humerus all move in an associated manner not yet defined clearly
Movement analysis not an exact science
Movement Basics
Basic Movements
Throwing – force summation where forces overlap in sequence (involves rotational components)
Pushing – all joint move simultaneously (translation)
Squatting – all joints move together (translation)
Pulling – is it rotational or translation?
Translation
If a body is moved from one position to another, and if the lines joining the initial and final points of each of the points of the body are a set of parallel straight lines of length ℓ, so that the orientation of the body in space is unaltered, the displacement is called a translation parallel to the direction of the lines, through a distance ℓ.
– E.T. Whittaker: A Treatise on the Analytical Dynamics of Particles and Rigid Bodies,
Rotation
A rotation is a movement of an object in a circular motion. A two-dimensional object rotates around a center (or point) of rotation. A three-dimensional object rotates around a line called an axis. If the axis of rotation is within the body, the body is said to rotate upon itself,
Mathematically, a rotation is a rigid body movement which, unlike a translation, keeps a point fixed
Pulling Technique
Aaberg suggests – Start position of scapula in neutral Move both scapula and arms together Continue to retract scapula Pull arms till humerus parallel with
body or aligned with shoulders (if all joints move together -
translational)
Fees et al suggests Shrug with elbows locked and scapula
fully retracted Partial ROM Full ROM (If scapula becomes set and arms
move afterwards - rotational)
$64000 question
Is pulling a translational movement of rotational
movement?
Examples-Rotational Movement. Compound movements like throwing, or
kicking, Bigger slower muscles initiate action Smaller faster muscles build on the action
super imposing their forces on top of momentum already developed
Isolated movements like leg extension, leg curls, bicep curls Single joint rotation via action of muscle
above the joint Rotation occurs about the axis of the joint
Examples-Translational Movement Compound movements like Bench
press, squat, All joints start moving and complete the
movement at or about the same time utilising different muscles in an optimal way to achieve the fullest movement possible
Multiple joints and muscles contribute within their ability to the whole movement
Compound Pulling Movements Bent over row
DB Row
Chin up
Standing cable pull
a. Shoulder below b. Shoulder stopped c. Shoulder rotates
Once elbow passes trunk line and shoulder ceases to move to rear, movement becomes rotation
a. Shoulder below - translation
b. Shoulder above and stopped
c. Shoulder still but arm passed trunk line now rotation
Shoulder remains centrally positioned in all 3 shots but elbow never passes the trunk line, hence little rotation
Axis of rotation now involves the trunkThe shoulder and elbow has passed trunk line but has the movement become rotation at the shoulder?
Strength Training Application
What is the Training Focus? Thoracic position and curve Scapula stabilisers Large muscles of the back Rotator cuff Trunk rotation “core” muscles Re-patterning Combination of all
What is the Pulling Sequence? Should the scapula set first? Should the elbow bend with the
setting? Should the elbow cease moving at
the trunk line? Should the trunk rotate?
Scapula Setting
Some cases require retraining of the scapula positioning
Setting back and down, or in and down is not justified by research – find Neutral ??????
The need to engage the scapula stabilisers is important and may require initial strength training prior to full pulling movements.
Scapula stabilising automatically occurs prior to humerus movement
Injury prevention through scapula stability training is an important factor
Lowe
Grip Variations Alter Function Wide to narrow grips
Wide grips tend to allow more translational movements
High to low bars Low bar pulls to lower chest tend to
allow more rotational movements Supinated, pronated and neutral
grips Supinated grips tend to allow more
rotational movements
Adding rotation of the shoulder to the end of a pulling movement
Slow strength moves under high intensity transfer great force to small muscles of rotation if the elbow passes trunk line
Small muscles cannot complete the movement so enlist aid of other muscles causing postural adjustments to shoulder girdle
Are these scapula positional adjustments supporting the true function of the movement or a form of cheating
Under explosive or high speed movements the force summation reduces this stress and less adjustment of shoulder girdle occur.
In Summary
In slow strength training, movements should occur together unless retraining or rehabilitating a shoulder
If movement is slow or load is high take care with how far past the trunk line you allow clients to pull elbow
If this is a desired movement then be sure to account for postural adjustments of the shoulder girdle and trunk in this action and ensure light enough load that rotator cuff can manage
Aim to achieve push-pull ratios and ext-int rotation ratios appropriate to sport or activity.
References 1. Aaberg, E. 2006. Muscle Mechanics: Human Kinetics. 2. Badi, T, and Boushaala, A. Effect of One-Handed Pushing and Puling Strength at Different Handle Heights in
Vertical Direction. In: eds., 2008. 3. Baker, D, and Newton, R. An Analysis of the Ratio and Relationship Between Upper Body Pressing and Pulling
Strength. J Strength Cond Res 18: 3: 594-598, 2004. 4. Cordo, P, and Nashner, L. Properties of postural adjustments associated with rapid arm movements. J
Neurophysiol 47: 2: 287-302, 1982. 5. de Groot, J, van Woensel, W, and van der Helm, F. Effect of different arm loads on the position of the scapula
in abduction postures. Clin Biomech (Bristol, Avon) 14: 5: 309-314, 1999. 6. Fees, M, Decker, T, Snyder-Mackler, L, and Axe, M. Upper Extremity Weight-Training Modifications for the
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30-37, 2007. 8. Graichen, H, Hinterwimmer, S, Eisenhart-Rothe, R, Vogl, T, Englmeier, K, and Eckstein, F. Effect of abducting
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9. Greenfield, B, Donatelli, R, Wooden, M, and Wilkes, J. Isokinetic evaluation of shoulder rotational strength between the plane of scapula and the frontal plane. Am J Sports Med 18: 2: 124, 1990.
10. Hickey, B, Milosavljevic, S, Bell, M, and Milburn, P. Accuracy and reliability of observational motion analysis in identifying shoulder symptoms. Man Ther 12: 3: 263-270, 2007.
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12. Kebaetse, M, McClure, P, and Pratt, N. Thoracic position effect on shoulder range of motion, strength, and three-dimensional scapular kinematics. Arch Phys Med Rehabil 80: 8: 945-950, 1999.
13. Kibler, W. The Role of the Scapula in Athletic Shoulder Function. Am J Sports Med 26: 2: 325, 1998. 14. Kolber, M, KS, B, MS, C, and MA, H. Shoulder Joint and Muscle Characteristics in the Recreational Weight
Training Population. J Strength Cond Res 23: 1: 148-157, 2009. 15. Lee, S, and An, K. Dynamic glenohumeral stability provided by three heads of the deltoid muscle. Clin
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