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Chapter 9
Running, Jumping, Throwing, Kicking & Lifting
Running
• Walking to Running
– 5 m/s or 4.5 mph
• Complex interaction of body movements
• Walking: Double & Single Support
• Running; Single Support & Flight phase
As speed increases
• First increases to stride length
– Anatomic limitors
• Then all further increases in velocity due
to stride rate increases
As speed increases
• 60-40 Walk
• Run
– 50-50
– 30-70
– 20-80
Muscle Activity
• End Swing Phase
– Glut-max: Ecc Slow Hip Flexion
– Hamstrings: Ecc Slow Knee Ext
– Tibialis-Ant conc dorsiflex-ankle
• Early Stance
– Glut-max, quad, gastro -> extensions
– Tibialis-Ant (isometricaly ?) stabilize
• Late Stance
– Plantar Flexors give push
• Through out EMG increases in magnitute
– Absolute Time (decrease)
– Relative (increase of % cycle)
Life Span perspective …2+…
• Muscle strength and flight phase
– Stride Length, ROM, Trunk Rotation
• Levels
–
–
–
–
1 Arms Assist
Feet flat – swing leg abducted
2 Arms swing trunk rotation Knee Flexion speed increase
3 Arm swing increase
Heel- sagittal toe-off
4 Arm independent trunk opposition
– Older Adults
– Acute vs Chronic Injuries
Jumping
• Jumping
– Land on both feet
• Hopping
– Take off & Land same foot
• Leaping
– Take off from one foot land on another
Basic Jumps
• Counter-movement Stretch-Shorten-Cycle (SSC)
• Squat
• Hip-Knee
– Extensors
– Arms 10%
• End of Flight Phase
– Anticipatory
Life-Span …Jumping
• Children
– 2-2, 1-2, 2-1 … also forward
– Over objects
• SSC
Jumps
Jumping Injuries
• Knee Extensor Mechanism (KEM)
– Quads-patellofemoral-tendon
• Patellar
– Maltracking
– Tendinitis
– Chondromalacia (degeneration)
• Quads
– tendinitis
Throwing
• Upper Extremity launch a handheld object
through air
• Projectile (object) and Ballistics (study)
• Overarm-underarm
• Push – Pull?
• Trajectory – Apex
• Speed -Angle -Height
Throws …
Throwing Phases
• Preparatory
– Favorable position – ROM – larger inside
– SSC – Length Tension – Elastic Energy
• Action
– Proximal to Distal
• Recovery
– Slow down decelerate
Windup and Cocking
EMG – Muscle activity
Life Span …Throwing
• Arm action (back-forward)
• Trunk Hip
– Trunk – Hip flexion
– Pelvic – trunk rotation
– Uncoupling
• Ipsilateral movement
• Backswing
• Force production ROM
Throwing Injuries
• Impingement Syndrome
– Suprahumeral structure (supraspinatus, subacromial
bursae) against acromion & cocacoacromial ligament
• Medial Epicondylitis
– Medial epicondylitis (ME) is an overuse injury
affecting the flexor-pronator muscle origin at the
anterior medial epicondyle of the humerus. ME is
often discussed in conjunction with lateral
epicondylitis (LE), which occurs much more
frequently.
– ME:LE = 1:5
Kicking
• Proximal to distal
• Impact – non-weight bearing
• Phases
– Approach – Momentum Build Up
– Pre-impact –
• Non-kicking leg support –
• Thigh Swing -- thigh slow down before impact
– Impact
.1 seconds or less
– Follow Through
• Hip Muscles whiplike sequencing
– Knee extensors minimal? (force-velocity curve)
Life-Span
• ROM
• Push to impact
• Foot Placement
• Injuries
– Knee
– Ankle
Lifting Techniques
• Squat
Stoop
• National Institute of Occupational Safetty and Health
(NIOSH) http://www.cdc.gov/NIOSH/
• Keep load close to body
• Use legs
• Leg Extensors vs Trunk Extensors
• Anticipatory Postural Adjustments (APA)
Injury related
• Children Older Adults
– Muscle strength dependence
• Lifting and Back disorders
– $$
– 80%
– Reduce loads --- increase strength
• Safety Guidelines
Safety Guidelines
• Design work tasks that facilitate variety (i.e., don’t do too much of
any single thing).
• Avoid a fully flexed or bent spine and rotated trunk when lifting.
• Select a posture to minimize the reaction torque on the low back by
keeping the external load near the body.
• Minimize the weight being lifted.
• Do not immediately perform strenuous exertions after periods of
prolonged flexion.
• Avoid lifting or spine bending after rising from bed.
• Prestress and stabilize the spine during light lifting tasks.
• Avoid twisting while generating high twisting torques.
• Use momentum when exerting force to lower spinal loads.
• Avoid prolonged sitting.
• Adopt appropriate rest strategies.
• Maintain a reasonable level of physical fitness.