enhancement - national strength and conditioning ... 1 performance enhancement training for the...
TRANSCRIPT
5/22/2013
1
Performance Enhancement Training for the Post‐Rehabilitated Knee
Robert A. Panariello MS, PT, ATC, CSCSProfessional Orthopedic and Sports Physical Therapy
Professional Athletic Performance CenterNew York, New York
NSCA National Conference
July 11, 2013
“If you do what you’ve always done, you’ll get what you’ve
always gotten”Timothy J. Stump MS, PT, USAW
5/22/2013
2
“In a competitive atmosphere, to stay the same is to regress” – NFL Hall of Fame Coach Bill Parcells
Thank You
• Don Chu
• Charlie Francis
• Derek Hansen
• Al Miller
• Johnny Parker
• Tim Stump
• Al Vermeil
• And so many others
Athletic Performance• The world class athletes, who run the fastest, jump the highest, throw the hardest,
etc. are those who apply the greatest amount of force into the ground surface area.
• Work = Force X Distance
• Power = Force X Distance over TIME!
– The fastest athletes spend the least amount of time on the ground (0.07‐0.09 sec at sprinting speed)!
– Main determinant of achieving maximum sprint speed was in reducing the contact time during the stance phase!
Mann 1998
Chu, Miller, Parker, Vermeil
5/22/2013
3
Athletic Performance• “Because of the narrow constraints on the minimum swing times and maximum contacts lengths that runners can use, speed is conferred predominately by an enhanced ability to generate and transmit muscular force to the ground.”
Weyand J Appl Physiol 2000
Ground Contact Time
• Sprinting – 100m Ground Contact Times
GCT and Horizontal Velocity
Ralph Mann
5/22/2013
4
The Running Gait Cycle• Stance Phase – 40% of the cycle• Swing Phase – 30% of the cycle• Float Phase – 30 % of the cycle• The majority of the Running cycle is spent with the leg off the
ground, therefore we must take advantage of the limited time spent on the ground
The Running Gait Cycle
• Since the Running Gait Cycle is a “Cycle”, any negative affect upon any phase of the “Cycle” will have a negative affect upon the entire running cycle
Poor Swing Phase Poor Stance Phase
Poor Stance Phase Poor Swing Phase
The Running Gait Cycle
• The Swing Phase
• The heel is placed on the inferior aspect (area of the gluteal fold) of the buttock
– Essential for a short lever arm resulting in efficient swing phase
– AROM knee flexion is essential for running success
5/22/2013
5
The Swing Phase
• Active knee ROM important for restoring speed
• Restoring normal mechanics of running
• Moment arms (distance) of heel to butt
The SwingPhase
Figure 1 Figure 2
Active Knee Range of Motion• After knee surgery athletes lose the ability to actively touch their butt with
the heel of the foot
• This inability is a biomechanical disadvantage in sprinting performance
– Longer lever arm in swing phase of sprinting gait
– Requires an extra .01 sec per stride
• 40 Yard Dash requires 18 to 20 strides
– Decreased 40 yd. time of .09 to .1 seconds (single leg)
Seagrave
5/22/2013
6
Rearview
Restoring Active Knee Flexion
• Butt Kicks
– Knee down
– Knee up
• Mach Drills
– “A” Skip
– “A” Runs
The Physical Qualities of Athletic Performance
• Enhancement of the various physical qualities of strength is necessary for the application of optimal force production into the ground surface area
Vermeil’s Hierarchy of Athletic Development
5/22/2013
7
Hans Selye’s General Adaptation Syndrome (GAS)
We need to stress the body for adaptation to take place!!!
The Physical Quality of Strength
• Maximum strength – the maximum amount of force that a muscle can exert
• No time requirement– Squat
– Deadlift
– Bench Press
– Overhead Press• Military
• Push Press
The Physical Quality of Strength
• Foundation of Athletic Performance
– Application of force into the ground surface area
– Maintenance of proper postural position during running
– Muscle and Joint Stiffness (requirement for SSC)
– Joint Stability
• Co‐activation index at or close to 1:1
– The physical quality necessary for all other physical qualities to develop
5/22/2013
8
The Physical Quality of Strength
• ACL Reconstructions
• Limb asymmetries in muscle strength and performance are consistently noted following the return to high‐level activity
– Squatting
– Jumping
– Landing
Risberg JOSPT 1999
Meyer JOSPT 2011
Neitzel Clin Biomech 2002
Paterno JOSPT 2011
The Physical Quality of Strength
• Squat Exercise
– Provides a Foundation of strength
– Descent ‐> Eccentric ‐> Deceleration (i.e. landing)
– Ascent ‐> Concentric ‐> force applied to the GSA
• Two (2) Questions
– How do I eliminate the “shift” during the descent?
– How deep do I squat?
“Posting” for the Squat Exercise• Often when performing the squat exercise, the athlete will “shift” their body away from the injured/surgical knee during the decent phase of the exercise. “Posting” the non‐op leg assists in correcting this shift.
Shifting away from the surgical extremityPosting the “good” extremity to correct the exercise “shift”
Post-op kneeNon-op Knee
5/22/2013
9
How Deep Do I Squat?
Maximum Quadriceps Activity During Squat Exercise
Muscle Knee Flex/Knee ExtSquat
(Degrees)
Rectus Femoris Knee Descent 83 - 95
Knee Ascent 95 - 83
Vastus Medialis Knee Descent 71 - 95
Knee Ascent 59 - 95
Vastus Lateralis Knee Decent 69 – 95
Knee Ascent 55 - 95KF = Eccentric DecentKE = Concentric Ascent
Vertical Hip Height (Strength) in Sprinting
• Appropriate vertical hip height:– Decreases ground contact times (i.e. properly inflated tire)
– Allows the hamstrings to work as a hip extensor vs. a knee flexor (increased “pawing”)
5/22/2013
10
The Physical Quality of Power
• The rate at which work is done per unit of time
• Power = Force X Distance/Time
The Physical Quality of Power
• Maximal Strength must be combined with either power (explosive strength) and/or reactive strength to enhance optimal athletic performance
• P = F X D/T Velocity Component
– Acceleration
– Rate of Force Production (RFP)
– The Co‐activation index is reduced with high speed training
Harris 2000, Tricoli 2005
The Physical Qualities of Strength vs. Power
• ACL Reconstructions
• 6 Months Post –op
– MVIC (Strength) ‐ 97% Pre‐injury level
– Rate of Force Development (RFD) – 63% Pre‐injury level
• 12 Months Post –op
– Rate of Force Development (RFD) –attained or exceeded 90% Pre‐injury levelAngelozzi JOSPT 2012
Angelozzi JOSPT 2012
5/22/2013
11
The Physical Quality of Power• Acceleration – transpires from a “preparatory” slower movement velocity followed by a higher velocity movement– i.e. NASCAR
• Olympic Weightlifting– 1st Pull transition to the 2nd pull– Requires bar acceleration from a slower preliminary speed
Peak Power Output
0
500
1,000
1,500
2,000
2,500
3,000
3,500
4,000
PowerClean
HangPowerclean
Mid-thighPowerClean
Mid-thighCleanPull
Power Clean
Hang Power Clean
Mid-thigh Power Clean
Mid-thigh Clean Pull
Comfort JSCR 2011
Pow
er (
W)
The Physical Quality of Power
• The Rate of Force Development (RFD)
MVIC
TIME
FO
RC
E (
N)
200 ms or less
300 ms or greater
Time to develop muscular strength in sportsTime for Max Contraction Strength
Aagaard Appl Physiol 2006
5/22/2013
12
The Physical Quality of Power
• Rate of Force Development (RFD)• ACL Reconstructions – Pre‐injury RFD levels take a year to return
• RFD – No preparatory bar movement. Initial bar velocity is zero i.e. Drag Race Car
• Olympic lifts from blocks– Below the knee– At the knee– Above the knee– Mid‐thigh– At the hips (Power Position)
Angelozzi JOSPT 2012
Comparison of Peak Rate of Force Development (RFD)
0
2,000
4,000
6,000
8,000
10,000
12,000
14,000
16,000
PowerClean
HangPowerClean
Mid-thighPowerClean
Mid-thighCleanPull
Power Clean
Hang Power Clean
Mid-thigh Power Clean
Mid-thigh Clean Pull
Comfort JSCR 2011Rat
e of
For
ce D
evel
opm
ent
(N/
s)
Peak Rate of Force Development (RFD) for Different Activities
0
50
100
150
200
250
300
MTCP VJ CMJ
Mid-thigh Clean Pull
Vertical Jump
Countermovement Jump
Tim
e (m
illis
econ
ds)
Kawamori JSCR 2006
5/22/2013
13
Comparison of Peak Ground Reaction Forces
0
500
1,000
1,500
2,000
2,500
3,000
PowerClean
HangPowerClean
Mid-thighPowerClean
Mid-thigh Pull
Power Clean
Hang Power Clean
Mid-thigh Power clean
Mid-thigh Clean Pull
Comfort JSCR 2011
For
ce (
N)
The Physical Quality of Elastic/Reactive Strength
• Elastic/Reactive Strength incorporates the Stretch Shortening Cycle (SSC)
• Accomplished by ‘shock” or “Plyometric” type training
• Short Amortization Phase
– Requires muscle and joint “stiffness”
• Olympic Lifts
– Barbell requires a second knee bend to clear the knees
– 2nd knee bend produces a SSC/RS quality at the Achilles and Patella Tendons enhancing the neuromuscular training of the musculoskeletal system for enhanced force output
Elastic (Strength) Energy When running tendon is the primary site for the
storage of elastic energy (EE) During the SSC storage of potential/EE during
the eccentric contraction is utilized as kinetic/EE during the concentric contraction
Tendon stretches, recoils, and releases EE At least half of the EE utilized for body
propulsion comes from the Achilles and foot tendons!
5/22/2013
14
Single Leg Hop Test
• ACLR extremity had a great asymmetry compared to the non‐involved extremity
• The non‐involved extremity performance was less than that of those in the control group
Schmitt JOSPT 2012
Ground Contact Time
Ground Reaction Times (EE) in the Post‐Operative Knee
The absence of appropriate levels of elastic strength and stiffness will result in increased ground contact times during the stance phase of the running gait cycle.
A protective mechanism of increased ankle plantar flexion occurs at ground contact: Dampens the ground contact forces in an attempt to reduce impact forces upon the knee
Negative affect on EE, power, and speed production
5/22/2013
15
Restoring Elastic/Reactive Strength Qualities
• Initiate Ankling Drills
– Restoring the elastic strength properties of the Achilles tendon
• Initiate Mach Drills (“A” Series)
– “A” Walks, Skips, and Runs
• Also restores full knee flexion AROM
• Progress to Olympic Lifts and/or components of the Olympic Lifts (i.e. pulls)
Summary
• Restore AROM Knee Flexion
• Proper heel placement at inferior fold of the glut
• Establishes a proper and efficient swing phased during the running gait cycle
• Restore the Physical Quality of Strength
• Foundation of the Physical qualities of Strength
• Establishes Muscle and Joint Stiffness (prerequisite for SSC)
• Applied force into the ground surface area
Summary
• Restore the Physical Quality of Power
– Acceleration
– Rate of Force Development
• Restore Elastic/Reactive Strength qualities
• Reduced ground contact times
• Physiological energy efficiency
