Transcript Plyometric and Speed Training

Plyometric and Speed
Training: Part A
Explosion and Power
Introduction
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In terms of performance…athletes are always
looking for advantages to put them over the top
Use of plyometrics and speed training has been
used to develop that advantage for most sports
involving explosive and powerful movements
Plyometrics and speed training have become
important in increasing ability of athletes to
better control deceleration forces, which can
contribute to athletic injury
Introduction
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Plyometric Exercise: quick, powerful movements
preceded by a pre-stretch or counter-movement
followed by an immediate powerful concentric muscle
action
Speed: the ability to achieve a high velocity
The purpose of the plyometric and speed training is to
elicit the SSC to achieve increased power in important
athletic movements
Speed training essential works to do the same thing, but
also adds in technique and muscular strength to
produce larger ground forces, which allows clients to
run faster
Plyometric Mechanics and
Physiology
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Power: term used to describe the force-velocity
relationship
When done correctly…plyometric exercise can
effectively improve muscle force and power
Increased power production can be explained in
two ways:
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Mechanical and Neurological
Plyometric Mechanics and
Physiology
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Mechanical Model of Plyometric Exercise
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Elastic energy is stored following a rapid stretch and then
released during the concentric muscle action…this then
increase muscle force production
Series Elastic Component (SEC) is a major contributor to
force production…it includes some muscle, but it mainly
tendon
When the musculotendinous unit is stretched during
eccentric muscle action…the SEC acts like a coiled spring to
store elastic energy
Once and if immediate concentric action happens the stored
energy will be released to create increased force production
If there is no immediate concentric action then the energy is
wasted and lost as heat
Plyometric Mechanics and
Physiology
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Neuro-physiological Model of Plyometric Exercise
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This element involves a change in the force-velocity
characteristics of a muscle contractile elements
Concentric muscle action is enhanced through the stretch
reflex mechanism
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This is an involuntary response by muscles
Muscle spindles involved are sensitive to time and rate of stretch
Muscle spindles detect stretch and cause increased muscle activity
Just like the mechanical model, if not used immediately then the
increased muscle activity dissipates and the muscle relaxes due to
Golgi tendon organs kicking in (this is ideal for stretching!)
Plyometric Mechanics and
Physiology
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Stretch Shortening Cycle
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Simply put:
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Eccentric phase(deceleration phase)
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Amortization phase
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Muscle put on a stretch, preloading the agonist muscle group
Stores elastic energy for use in the concentric phase
Time between eccentric and concentric phases (end of eccentric to
beginning of concentric phase)
Phase must be kept in short duration for positive effects on force
production to take place (stored energy lost as heat if not immediately
used)
Concentric phase
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Muscle group action occurs causing release of stored elastic energy from
SEC
Increased muscle force production
Not effective if amortization phase is held too long (energy lost as heat)
When to Use Plyometric Exercise
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Plyometric Training and Sport Performance
Increased muscular power is an important and
necessary characteristics of most athletes and relates
to positive performance results
 Ideal for trying to improve muscle force production
 Prepares athletes for deceleration-acceleration and
change in direction requirements for athletic tasks
 Running economy improved as well in averagedistance runners
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When to Use Plyometric Exercise
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Plyometric Training and Work Performance
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There is some evidence that plyometric training can
be important for work performance
Police officers
 Firefighters
 Individuals preparing for the military
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All these professions must be able to run quickly, change
direction effectively, and jump onto or over objects to perform
their occupational duties
When to Use Plyometric Exercise
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Plyometric Exercise and Injury Prevention
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Studies have shown that athletic injury rate is decreased
following use of plyometric training programs
 Improves bone mineral content, muscle recruitment,
strength, body control, and balance
However, it has been difficult to generalize these results to
other populations
 Eccentric training may be a compromise for clients who
wish to engage in injury prevention activities but for
whom plyometric training is not appropriate.
When to Use Plyometric Exercise
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Contraindicated Populations
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Age
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Plyometrics are safe and beneficial for youth, as soon as a client is
mature enough to accept and follow directions.
Be mindful of high-intensity lower body plyometrics due to the
epiphyseal plates of prepubescent children still being open
Plyometrics are appropriate for adolscents
 Use low-intensity drills if all safety conditions have been met
Older clients should avoid high-intensity plyometrics, but low to
moderate plyometrics can be continued on an individual basis
Physical maturity is not the sole determinant of plyometric
predaredness.
When to Use Plyometric Exercise
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Experience and Training Level
Clients who have never participated in regular
resistance training programs should be prohibited
from participating in plyometric exercises
 Plyometric programs require a significant amount of
strength and neurological functioning so encourage
starting a regular resistance training program first
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Posture, Flexibility, and Stability
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A solid base of support is necessary for the traditional and nontraditional movement patterns used in plyometric training.
The partial or half-squat position is:
 Chin tucked in slightly
 The scapulae are slightly retracted
 The trunk is parallel to the tibias
 Knees are directly over or slightly posterior to the toes, and
heels should remain on the ground.
Once the client can hold the position above progress to the
bodyweight squat
Posture, Flexibility, Stability
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Once the client can hold a proper double-leg
squat position and perform a proper body
weight squat, they may begin low-intensity
plyometric exercises.
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They must learn to maintain the proper alignment,
providing a strong base for dynamic action.
Posture, Flexibility, and Stability
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Before increasing the level of plyometric exercises, the client
should be able to hold a single-leg squat position as described for
the balance tests shown in table 17.2, pg. 417
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Each test position must be held for 30 seconds
Strength
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Before adding plyometrics to a client’s workout
program, the personal trainer must also take the
client’s level of strength into consideration.
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For lower body plyometrics, the client’s 1RM squat should be at least 1.5
times his or her body weight
For upper body plyometrics, clients weighing more than 220 pounds
should have a bench press 1RM of at least 1.0 times their bodyweight;
those under 220 pounds should have a bench press 1RM of at least 1.5
times their bodyweight
An alternative measure of prerequisite upper body strength is the ability
to perform five clap push-ups in a row
Medical History and Physical
Characteristics
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Medical clearance is prudent for any client with
a diagnosed condition.
Physical characteristics
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Clients who weigh above 220 pounds are at
increased risk and should avoid high volume
plyometrics
No depth jumps greater than 18 inches tall
 Plyometric exercises should be limited to those involving
double-leg take offs and progress to single-leg when
proficient with double-leg.
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Speed
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For lower body plyometrics the client should be able to perform
five repetitions of a squat with 60% of body weight in 5 seconds
or less
For upper body plyometrics the client should be able to perform
five repetitions of the bench press with 60% bodyweight in 5
seconds or less
If the client lacks the necessary speed they may begin a lowintensity plyometric program that does not rely heavily on speed
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Two-foot ankle hop, standing long jump, double leg vertical jump
Landing Position
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Shoulders over the knees, knees should be
slightly over or slightly posterior to the toes,
with the ankles, knees, and hips flexed and the
feet approximately shoulder-width apart.
Weight should be placed more on the ball of the
foot and not the heel to facilitate quick turn
around on landings and enhance control of the
center of gravity
Equipment and Facilities
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Landing surface
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Training Area
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Adequate shock absorption (grass field, turf, suspended floor, rubber
mats)
Hardwood, concrete, and tile are not recommended as they are not
sufficiently shock absorbent
Bounding and running require 33 yards of straightaway, and up to 109
yards
Most standing, box, and depth jumps require an area of 9.8 to 13.2 feet,
but adequate height is necessary
Equipment
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Boxes should have a non-slip top, be closed on all sides
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Height can range from 6 to 42 inches with a landing surface of at least 18 by 24 inches
Plyometric Program Design
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Needs Analysis: Evaluate the client’s current abilities before
plyometric exercises begin
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Age: does age predispose client to injury and therefore preclude them
Training experience or current level of training: has client been resistance
training? What types of exercises has client been performing? Plyometrics
before?
Injury history: currently injured? Have any previous injuries that would
affect plyometric training status?
Physical testing: what are clients capabilities in relation to power
production
Training goals: what does client want to improve? Particular skills
Incidence of injury in a client’s job or chosen activity: what is risk of
injury in chosen activity?
Plyometric Program Design
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Mode
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Which kinds of plyometric exercises are appropriate based on
client goals and specific sporting involvement
Lower Body
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Appropriate for clients in almost any sport
Requires participants to produce maximal force in a minimal amount
of time
Clients in sports like basketball would benefit greatly from lower
body plyo’s due to repetitive jumping involved in the sport
Types of lower body plyo’s…depth jumps, standing jumps, bounds,
box drills, etc.
Plyometric Program Design
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Upper Body Plyometrics
Rapid upper body movements are required in a
variety of sport such as golf, baseball, football and
tennis
 Not used as often, but are very effective nevertheless
 Examples include…med ball throws, catches, and
push up variations
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Plyometric Program Design
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Intensity
Refers to the amount of stress placed on the
muscles, connective tissues and joints and is
controlled by the type of drill performed and
distance covered
 Intensity ranges from low-level to high-level
 Intensity should be kept low for beginners
 Efforts should be geared towards technique rather
than volume to help prevent injury
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Plyometric Program Design
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Intensity
Better to underestimate than overestimate
 Youth and adolescents should begin with one or two
sets of 6-8 repetitions to ensure quality reps each set
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Plyometric Program Design
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Frequency
Number of plyometric training sessions per week
 Depends upon client’s goals
 Optimal frequency is limited in terms of research
 Two times per week for moderate intensity
plyometrics is best
 For youth: Two non-consecutive days per week is
recommended
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Plyometric Program Design
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Recovery
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Amount of time or rest between plyometric exercises
Depends upon work to rest ratio (range of 1:5 to 1:10) and is
specific to volume and type of drill being performed
Higher intensity of a drill, the more rest a client requires
Rest times of 60-120 seconds between drills should allow for
full or near full recovery
48 to 72 hours between plyometric sessions is recommended
Plyometric Program Design
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Volume
Typically expressed as number of repetitions and
sets performed during a training session
 Lower body plyo’s expressed as number of foot
contacts (e.g. bounding contacts)
 Upper body usually expressed as number of throws
or catches
 Refer to Table 17.6 (pg. 425) for volume guidelines
by age and experience level
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Plyometric Program Design
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Progression
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Plyometrics is a form of resistance training so it
must adhere to principles of progression such as
overload and F.I.T.T
As intensity increases, volume decreases
 Landing first
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Horizontal or vertical components
 Double leg before single leg
Plyometric Program Design
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Warm Up
Plyometric exercise should begin with general and
specific warm ups
 General may consist of light jogging or stationary
bike, etc.
 Specific would be dynamic movements similar to
those in plyometric training
 See Table 17.7 (pg. 426) for examples of plyometric
warm up drills
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Safety Considerations
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Maturity
Caution with children under 14 yrs old and older
than 60 yrs old
 Clients must also respond positive psychologically to
specific instructions
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Safety Considerations
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Clients must be closely monitored to ensure
proper technique
Plyometric exercise once again is not inherently
dangerous, but supervision helps reduce injury
prevention