Phase One - xdocs.net

The Body as OneUpper Extremity Movement Mechanics

By: Fabio Comana, MA., MS. NASM CPT, CES, PES; NSCA CSCS; ACS< HFS: ACE CPT, HC; CISSNNASM Faculty Instructor

April 24, 2014

Scapulothroacic Region = Stable

Thoracic Spine = Mobile

What Do You Want to Learn?

Learning Outcomes: • Describe the overall function of the human body in

movement.

• Explain primary components of human movement science.

• Administer and interpret an upper extremity movement screen.

• Implement a simple UE corrective exercise program.

• Instruct proper mechanics for UE movements.

Movement• Fundamental trait we all share – improve movement efficiency.

o Requires appropriate levels of simultaneous stability and mobility.

What happens when the Software or Hardware becomes faulty?

Stability

Ability to maintain or control joint movement or position

Mobility

Possessing uninhibited 3-D ROM around a joint or body segment

Must Never Compromise Each Other

Foot = Stable

Knee = Stable

Lumbar Spine = Stable

Scapulo-thoracic Region = Stable

Ankle = Mobile

Hips = Mobile

Thoracic Spine = Mobile

Glenohumeral = Mobile

Examining the Body as One

Movement

Movement

What Happens if the Body Loses / Lacks this Relationship?

• Step One: Law of Facilitation = ‘Dyskinesis’o Compensation: Compromised stability to facilitate mobility.

o Compensation: Movement into other planes.

Example: Bird-dog

Why?

Movement and InjuriesWhat Happens if the Body Loses / Lacks this Relationship?

• Step Two: Loss of stability = injury potential.o Chronic overuse injuries versus acute injuries.

Low back – stable ! Knees – stable ! Shoulder girdle – stable !

80 – 90 % of all adults 200,000 ACL injuries/year. 70 – 75 % non-contact.

21 % of population with 40% persisting < 1 year

$100 billion annually $650 million (surgery + rehabilitation)

$39 billion annually

Sport & Exercise-related Injuries

Injuries in Recreational & Sports Facilities

Sprain/Strain-type Injuries

1997 13.4% of all injuries 11.6% of all injuries 26.4% of all injuries

2007 17.9% of all injuries 15.0% of all injuries 30.7% of all injuries

Look at popular programs since 2004 – What will happen to injuries between 2007 and 2017?

Movement MechanicsSpecifics: Shoulder Abduction

Frontal Plane Action

Application: • Internally rotate the arms and abduct as high as possible – notice end ROM.• Externally rotate the arms and abduct as high as possible – notice end ROM.

Difference?• Impingement of greater tuberosity (humerus) against coracoid process (scapula) - space is generally small

(~ 5-10 mm).

Implications for Movement:

• Caution against excess shoulder abduction with internal rotation = bursitis and tendonitis (supraspinatus and biceps long head).

• Example: Upright rows, front and lateral raises.

Movement MechanicsSpecifics: Shoulder Abduction

Scaption Plane Action

Application: • Perform a lateral raise movement with the arms in the frontal plane – notice any resistance to movement?• Perform a lateral raise movement with the arms 30° forward in the frontal plane – notice any resistance to

movement?

Difference?• With arms 30° forward to frontal plane, greater tuberosity falls in line with highest point of coraco-acromial

arch - experiencing least amount of resistance.

Implications for Movement: • Perform lateral raises with slight external rotation or forward 30° in frontal plane. • Example: Moving from 3 / 9 o’clock position to 4 / 8 o’clock position for shoulder flexion exercises (press,

lat pull-down, lateral raises).

Movement MechanicsSpecifics: Overhead Press

Frontal Plane Action

Application: • Three heads offer anterior, middle and posterior containment of shoulder (lowered position).• Place index finger and thumb over origin and insertion points of anterior deltoid - perform overhead raise

movement.

Difference?• Observe external rotation of humerus - changes muscle’s orientation. • Arm lowering - no anterior stabilizer to prevent anterior humeral displacement (exacerbated with behind

the head presses).

Implications for Movement: • Overhead positions – External humeral rotation creates no anterior containment beyond passive structures

– need to engage lats as stabilizers.

Force-Coupling VectorsDirection, Magnitude and Timing Movement application?

Scapulohumeral Rhythm

• 180° abduction - scapular and glenohumeral (GH) joint movement ratio = ~ 2-to-1.

o 2° of GH motion for every 1° of scapular motion (120°-to-60° ratio).

• True scapulae movement = 45 – 60° upward rotation coupled with:

o 20 – 40° posterior tilt.

o 15 – 35° external rotation.

o All designed to reduce encroachment into sub-acromial space.