Plyometrics: Jumping into Rehab

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Transcript Plyometrics: Jumping into Rehab

Regaining Speed for Sport
in Rehab
Trina Radske-Suchan, PT, CSCS
Why Speed Training in Rehab?
Prepares body for sport-specific
stress/loads
Enhances sport-specific
neuromuscular patterns
Increases muscle efficiency
Decreases risk of further sports
injury
OPTIMAL SPORTS PERFORMANCE
General POC
Regain ROM
Recover Balance
Regain Strength
Train Muscle Endurance/Conditioning
Develop Plyometric skills
Speed Training
Regain Strength
Static Strength
– Open and closed kinetic chain exercises
VMO, Hamstrings/Glutes, Hip
– Build a strong foundation
Dynamic or Functional Strength
– Needs to involve core
– Multi-joint movements
– Whole body coordination
Sport Specific Strength
Sport Specific Strength
Strengthening specific to explosive
sprinting
Force x Velocity= Power
Therefore, one needs to tolerate
developing power in order to return
to sprinting
DB snatch; resisted HS turnover or
knee drive
Specificity of Training
According to theory of “Specificity of
Training”, what are we doing in the
clinic that is specific to running or
sprinting?
Why is this important?
How would a patient be best
prepared for a plyometric activity
such as running or sprinting?
Specificity of Training
Specific exercise elicits specific adaptations, thus
creating specific training effects (McArdle, Katch,
& Katch 1981)
Functional exercise works on the principle of
specificity of training
In this case, how are we addressing speed which
is functional for most athletes?
Running is Plyometric
Running is a plyometric activity
Plyometric training is a type of athletic
enhancement thought to produce
significant improvements in maximal
strength, power development, increasing
speed, improving vertical jump height,
and reducing injury
– Masamoto et al 2003, Matavulj 2001, Diallo et al 2001, ACSM
2001, Rimmer and Slievert 2000, Hewett et al 1996, Newton and
Kraemer 1994, Bedi et al 1990, Borkowski 1990, Radcliffe and
Gambetta 1986, Bosco et al 1982.
Science behind Plyometrics
A muscle that is stretched prior to a
concentric contraction will contract
with more force and contract more
rapidly
Produces a more explosive action
Mechanical versus Neuromuscular
Models
Stretch-Shortening cycle
Mechanical Model
Muscles and tendons create elastic energy
Elastic energy is stored as a result of a stretch
Energy is lost if not followed by immediate
contraction
Energy is released when followed immediately by
a contraction
Series elastic component
Eccentric contraction loads the muscle prior to
the explosive concentric contraction
The faster and greater the load, the more
powerful the contraction
Neuromuscular Model
A neuromuscular event
The Stretch Reflex causes the muscle to contract
in response to being stretched
– Stretch (how much and how fast) activates the sensory
spindle receptors in the muscle
– Message is sent to spinal cord via one synaptic junction
– Motor horn cells in spinal cord respond as a protective
mechanism
– Causes a contraction of muscle
– Inhibits the antagonist muscle from contracting (Chu
1983)
– Results in powerful concentric muscle action
Stretch Reflex
Develop Plyometric Skills
Plyometric Training
Plyometric training utilizes powerful
muscle contractions to enhance the
explosive movements used in sports
The fundamental reason to train with
plyometrics is to reduce the ground
contact time that an athlete spends when
running or jumping (“Plyometric Training
for Youth”, www.donchu.com)
Speed Training
This type of training enhances an athletes
ability to increase speed of movement and
improve power production (American
College of Sports Medicine, 2001)
The use of speed/sprint training is an
applicable training method of improving
explosive performance of athletes (J
Strength Cond Res. 2007)
Clinical relevance: Both plyometric and
dynamic stabilization/balance exercises
should be included in injury-prevention
protocols (Am J Sports Med. 2006)
History of Speed Training
Prior to the 1960’s, genetics were
believed to be the only factor in
determining an athlete’s speed or
quickness.
History of Speed Training
1960’s – Began questioning the theory of
genetics & began testing neuromuscular
system to see if different training techniques
influenced speed
1960’s – Dr. Dintiman towed athletes behind
a motor scooter and automobile to force
faster speeds and longer strides
Mid 1970’s – Bob Ward was hired as the 1st
full time strength & conditioning coach for the
Dallas Cowboys to include speed training
Clinical Assessment
Identify strengths and weaknesses to
design an individualized speed
improvement/rehab program or to assess
readiness for speed training after injury
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Strength
Muscle Balance
Flexibility/ROM
Power
Quickness/Agility
Sprint Form/Mechanics
Past Medical History
Assessing Sprint Mechanics
Physical therapists should know what to
look for when assessing running and
sprint mechanics
Patients do not automatically regain
speed for sport after injury
Not unlike gait training in the clinic
No other profession can assess motor
deficits or movement disorders as well
as physical therapists
Sprint Mechanics
Thigh rises to parallel
Touchdown is under the
body’s center of gravity
Touchdown is with ball of
foot
~145° angle between
thighs
Compare to Longer Distance
Running Mechanics
Thigh rises to 45°
Touchdown is slightly in front
of the body
Touchdown is with the entire
foot (foot rocker)
~90° angle between thighs
Sprint Mechanics
Arm Action
 Counteracts hip & leg rotational
forces
 Keeps body aligned
 Maintain 90° elbow angle
 Hands & shoulders stay relaxed
 Thumb to nose level & hand past
buttocks
Arm Action
Sprint Mechanics
Leg Action
 Foot dorsiflexed except during ground contact
 Foot should leave ground in a straight line
towards buttocks
 As speed increases heels get closer to buttocks
 Knee drives close to 90°, thigh parallel to
ground, pelvis maintains posterior tilt
 Knee extends & straightens underneath hip
 Stride completion is ensured with a powerful
“push-off” the ground
Sprint Mechanics
Sprint Mechanics
Posture
 Acceleration: 45° lean
 Maximum speed: 70° to erect
 Straight line from ankle to head
Sprint Drills in the Clinic
Ankling
 Quick “push-off” ground with balls of feet
 Minimize ground contact time
 Emphasize quick “toe-up”/dorsiflexion
Straight Leg Shuffle
 Straight-legged ankling
 Shuffle picks up tempo as you incorporate arm drive
A’s
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Focuses on beginning of running cycle
Alternate knee drives, up & outwards
Be explosive with knee drives
Foot plants underneath hips
Forward progression
Sprint Drills
B’s
 Continuation of A’s
 As knee drives up & outwards, kick heel
straight ahead
 Pull down & sweep heel under hip in a
cyclic manner
C’s
 Heel is drawn up towards buttocks
 In a cyclic manner, heel accelerates down
toward ground
 Foot “paws” ground & heel draws back up
to buttocks
Sprint Drills
A Skips
 If there is room in clinic
 Drive knees upwards & outwards in skipping
motion
 Aim for height & distance over the ground
 Minimize ground contact time
 Knee drive is explosive
Sprint Drills
High Knees
 Alternate knee drives as quickly as possible
 Minimize ground contact time
 Include appropriate arm drives
Pawing Drills
 Individual uses support of wall or fence
 Starting position: opposite knee 90° & thigh
parallel to ground
 Foot is dorsiflexed or in “toe-up” position
 On cue: foot drives towards ground, “paw”
ground, heel pulls towards buttocks in a cyclic
manner
Sprint Drills
Wall Drills
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Aim: quick knee drives & minimize ground contact
Position: facing against wall
Practice at varying degrees of body lean
One leg in 90° of knee flexion, foot in “toe-up” position
On cue: quickly switch leg position
Fast Leg Drill
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Much like C drill except incorporated into running rhythm
Can do single or alternate leg
Emphasize quick turnover
Pattern: Stride, stride, fast leg, stride, stride, fast leg
Include appropriate running arms
Plyometric Drills for Speed
Development
DL – DL jumps
SL – DL jumps
DL – SL jumps
Tuck jumps
Lateral hops
Alternate leg hops/bounds
Single leg hops/bounds
Enhancing Sport Specific
Speed
Instructions to patient’s coach or trainer
Increase stride length
 Incorporate speed resisted training
Increase stride frequency
 Incorporate speed assisted training
Improve quickness
 Incorporate sport specific agility & plyometric
drills
↑Speed = ↑Stride Frequency &
↑Stride Length
Stride Frequency
 Number of strides taken in a given time
or distance
 Increased by speed-assisted training
Speed-Assisted Training
 Bungee cord running
 Down hill running
↑Speed = ↑Stride Frequency &
↑Stride Length
Stride Length
 Distance covered from heel strike of left foot to
heel strike of left foot again
 Optimal stride length is 2.3 – 2.5x leg length
at full speed
 Increased by speed resisted training
Speed Resisted Training
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Weighted vests
Parachutes
Weighted sled
Partner resisted running
Bungee cords
Periodized Training
Speed training should be
accompanied by continued strength
training and addition of power
training
Periodized training is the best
method to reduce over-training
injuries and optimize training effects
References
American College of Sports Medicine, “Plyometric Training for
Children and Adolescents,” December 2001, www.acsm.org.
Baechle, T.R., Earle, R.W., eds. Essentials of Strength Training
and Conditioning, 2nd ed. Champaign, IL: Human Kinetics. 2000.
Chu, D.A. Jumping into Plyometrics. 2nd ed. Champaign, IL:
Human Kinetics, 1998.
Dintiman, G., Ward. Sports Speed. 3rd ed. Champaign, IL: Human
Kinetics. 2003.
Dintiman, G., Ward, B., Tellez, T. Sports Speed. 2nd ed.
Champaign, IL: Human Kinetics. 1997.
Foran, B., ed. High Performance Sports Conditioning. Champaign,
IL: Human Kinetics. 2001.
Kotzamanidis C. Effect of plyometric training on running
performance and vertical jumping in prepubertal boys. J Strength
Cond Res. 2006 May;20(2):441-5.
Markovic G, Jukic I, Milanovic D, Metikos D. Effects of sprint and
plyometric training on muscle function and athletic performance. J
Strength Cond Res. 2007 May;21(2):543-9.
References
Myer GD, Ford KR, McLean SG, Hewett TE. The effects of
plyometric versus dynamic stabilization and balance training on
lower extremity biomechanics. Am J Sports Med. 2006
Mar;34(3):445-55.
Norkin, C.C., Levangie, P.K. Joint Structure and Function. 2nd ed.
Philadelphia, PA: F.A. Davis Company. 1992.
“Plyometric Training for Youth”, Donald A Chu. www.donchu.com
Radcliffe, J.C., Forentinos, R.C. High Powered Plyometrics.
Champaign, IL: Human Kinetics. 1999.
Saunders PU, et al. Short-term plyometric training improves
running economy in highly trained middle and long distance
runners. J Strength Cond Res. 2006 Nov;20(4):947-54.
Spurrs RW, Murphy AJ, Watsford ML. The effect of plyometric
training on distance running performance. Eur J Appl Physiol.
2003 Mar;89(1):1-7.
Yeisis, M. Explosive Running. Chicago, IL: Contemporary Books.
2000.
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