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Plyometrics3.pptxPlyometrics
Chapter 7
Introduction
Power—a combination of speed and strength—is required for nearly all athletic movements.
Jumping
Bounding
Hopping
have long been used to enhance power & improve athletic performance.
Plyometrics - develop explosive reaction through powerful muscular contractions as a result of rapid eccentric contractions.
Plyometric Training
Plyometric Exercises Develop:
Physical Power
Quickness
Traditional weight room exercises don’t allow the athlete to move quickly enough or use movements needed to develop sport-specific power.
Mechanics of Plyometrics
Speed & Strength are directly affected by:
Muscle’s fiber type (fast or slow twitch)
Speed of muscle contraction
Speed & efficiency of neuromuscular firing
Plyometric training - the key to improving 3 muscle characteristics
Train fast- & slow-twitch muscle fibers
Power has a greater effect on fast-twitch fibers over slow-twitch fibers.
Forcing slow-twitch aerobic fibers to contract faster improves firing capability as well.
Mechanics of Plyometrics
All training forces fibers to take on characteristics of muscle fiber type common to sport
Ex: Sprinters = force slow –twitch fibers to adjust to more rapid firing
No immediate change
Adaptation must occur
Could take up to years
Reason sprinters continue to gain speed
Mechanics of Plyometrics
Plyometrics help the muscles produce greater force by causing it to rapidly produce that force.
Pre-stretch helps propel athlete to the side faster.
How and why do your muscles react to prestretch?
Muscle spindle types:
Muscle Spindle – muscle belly
Glogi Tendon Organ – within tendon of muscle
Muscle Spindle
Deep in muscle belly, along fibers
Registers & sends information about stretch & length of muscle to spinal cord
If severe/rapid stretch is detected, message is sent for muscle to contract
While muscle is contracting process of reciprocal inhibition occurs.
Reciprocal Inhibition – tells opposite/antagonistic muscle not to resist agonists muscle contraction
Ex: Patella Tendon reflex testing
Causes quadriceps to contract, lower leg raises rapidly, while hamstrings release from contracting (reciprocal inhibition)
Golgi Tendon Organ (GTO)
Registers changes in tension & stretch within tendon
Helps protect muscle by sending signal when tension is too great
Tells muscle to stop contracting
Causes opposite/antagonist muscle to contract
Ex: Curling heavy dumbbell (greater than 1 RM)
Biceps relax = tension is too great
Golgi Tendon Organ (GTO)
Reducing action of GTO:
Overload muscle at various positions along movement
Ex: Bench Press:
In safety rack, setting rack eight at position off chest
Lifter will push light loaded bar against it, creating maximal tension for 5-10 seconds
Elastic Energy
3rd concept in plyometrics
As muscle undergoes a pre-stretch – builds energy
If released promptly the energy aids in muscle contraction
Ex: pulling back on rubber band & releasing
If muscle is stretch & held too long = will not produce explosive effect
Will have to work harder to do same work
Portion of lift started by concentric/eccentric form:
Dumbbells = concentric
Barbell = eccentric
Machine = concentric
Elastic Energy
Eccentric movement =
Nervous system tells brain:
How much weight is present
How much stretch is occurring
How much counterforce is required
Eccentric contraction = GTO’s & muscle spindles do their jobs
Concentric movement = no elastic energy build up/stretch for receptors to monitor
Plyometric Components
3 Main Components of Plyometric Movement:
Eccentric Action
Amortization Phase
Concentric Action
Plyometric Components
Eccentric Component:
The initial pre-stretch or countermovement occurs
Process of storing potential energy for the movement
Amortization Phase:
Time where potential energy is converted to kinetic energy (movement) or the time it takes to repay the deficit obtained by energy buildup
Concentric Action:
The final force created to propel a person or implement upward or forward
Contraction should happen immediately once the pre-stretch has been reached or countermovement max point
Figure 7.1 pg. 149
Plyometric Sequence
Plyometric Sequence:
Landing or Loading phase
Amortization phase
Take-off phase
Landing or Loading Phase – begins as soon as muscles begin eccentric contraction
Rapid eccentric contraction stretches elastic component of muscle & activates the stretch reflex
Needed for landing phase
Amortization Phase – time on the ground
Most important part of plyometric exercise
Time from landing to take off
Crucial for power development
If this phase is too long, the stretch reflex is lost & there’s no plyometric activity
Plyometric Sequence
Take off Phase (Concentric)
Essential for power development
Follows landing
Too much impact time results in more time to recover
amortization time & decreasing force output
Stored elastic energy jump height
Categories of Plyometric Exercise
Single-Response Drills
One explosive effort
Repetition Land Pause Reset Focus on next effort
Multiple-Response Drills
Use skills developed while jumping in place & standing jumps
Single-Response Drills
Simplest form of plyometrics
Jumping in place
Standing jumps
Stress maximal effort in vertical & horizontal directions
Standing Jumps
Most often done onto or over boxes, hurdles, or other obstacles
Box Jumps
Performed by jumping for height on or over boxes/benches from single or double leg take off
Hurdle Jumps
Performed by jumping for height over hurdles from single or double leg take off
Single Response Drills
Depth Jumps
Jumping or falling from a height, followed by immediate rebound upward
Box height – determined by Maximum Vertical Jump Test (Ch. 2)
30 centimeter box
If individual does not have enough strength to do depth jumps, should focus on strength training and lower intensity plyometrics
Single Response Throws
Standing, sitting, lying
Involve single throw of medicine ball or weighted object for max height or distance
Multiple Response Drills
Use skills developed while jumping in place & standing jumps
Single Leg Jumps
Double Leg Jumps
Changes in direction or body orientation
Bounds
Multiple jumps for maximal distance
Hops
Normally performed over several cones or over & back across an object
Multiple Throws
Involve throwing ball back & forth to partner, catching, & releasing ball as quickly as possible
Goal: complete specific number of throws as quickly as possible or complete as many throws as possible in given period of time
Designing a Plyometric Program
Intensity
Measure of how hard an individual works
Compared to maximum amount of something an individual can do
Training Intensity
Factor in defining overall stress a training session creates
All repetitions in plyometric exercise are performed at maximal speed & power
Anything less stretch-shortening response & plyometric effect of movement ; reducing training effect
Designing a Plyometric Program
Designing a Plyometric Program
Intensity
Lunges – low intensity (little counter movement/pre-stretch, landing is light)
Jumping off box Landing Rapidly jumping again = High intensity
When landing on 1 or 2 leg(s), intensity is determined by initial movement
Ex: taking off from 1 leg = high intensity; taking off from 2 legs = low intensity
Guideline: The higher & longer the distance you cover in an exercise, the faster performance of the movement = higher intensity level
Plyometrics are recorded by the number of single-foot contacts with the ground
Contacts per session
Number of single-foot contacts with the ground
Ex: 80 contacts = 4 sets, 10 repetitions of a movement, uses both legs, or total of 80 steps with walking lunges
Designing a Plyometric Program
Designing a Plyometric Program
Contacts Per Set
Plyometric energy comes form anaerobic (ATP-CP) energy systems
Adenosine Triphosphate & Creatine Phosphate (phosphagens) are available for immediate use
Phosphagen stores are small & can only provide energy for about 5-15 seconds of all-out-effort
Plyometric Box Training
Normally 6 or < repetitons, unless rest period between jumps is long
Overtime – increase rep number/set time before fatigue
Designing a Plyometric Program
REMEMBER!!
Do NOT perform plyometric exercises more than twice per week
Unless sport requires movements that accelerate or change direction rapidly
Otherwise, two sessions per week is adequate
Rest between sets
Rest & recovery, crucial in plyometric program
Rest
Time between each exercise or set
Recovery
Amount of time needed before workout can be repeated
Rest period
Can last up to 7 minutes between sets or exercise
Rest depends on work & type of drill/exercise performed
Work period
Time it takes to perform action
Does not represent total time to complete each set
Designing a Plyometric Program
Table 7.3 pg 154: Fuideline for determining rest periods based on how long exercises take.
Note: Rest for prolonged sets should be between 3-5 mins between –exercise rest to as much as 10 mins.
Designing a Plyometric Program – Rest Periods
Rest Periods
Between sets, should last at least 2 minutes
Unless work period is short
Shorter rest periods aren’t sufficient for ATP-CP energy sytems to replenish phosphagen stores for lactic acid removal
ATP-CP energy system, mainly used when performing plyometric drills in sets of less than 8 reps
Buildup of lactic acid quantity & quality of work performed (inhibits power gains)
Lactic Acid
Lactic Acid
End product of anaerobic glycolysis
Can decrease pH in muscle
Chance of injury
Muscle fibers drop out of exercise, technique gets sloppy, makes it more difficulty to establish motor patterns
pH = enzymes stop functioning & muscle fibers stop producing energy
Avoid lactic acid build up
Interferes with release & update of calcium in muscle (necessary for muscle contraction)
Plyometric Drills – Body-Weight
Perfect technique first by using body-weight plyometric drills
Increase body-weight drills by performing with a single leg
Body-weight plyometrics
Great for soccer players
Great for aerobic sports (help develop power at level more appropriate for endurance athlete)
Plyometric Drills – Body Weight: Vertical Jump
Stand with feet shoulder-width apart.
Swing arms back & quickly dip until knees bend to about 120°
Explode upward extending knees, hips, ankles, & trunk while swinging arms forward & upward as explosively as possible.
Focus on completely extending body, reaching as high as possible.
Arm drive is important for reaching maximum jump height.
Plyometric Drills – Body Weight: Lateral Jump
Stand with feet shoulder-width apart.
Swing arms back & quickly dip until the knees bend to about 120°
Explode laterally extending knees, hips, ankles, & trunk while swinging arms forward & laterally as explosively as possible before landing.
Plyometric Drills – Body Weight: Split Jump
Begin in proper lunge position with forward leg flat on the ground & the back leg on the toes.
The front leg should be bent at 90°.
The trunk should be upright.
The body should remain in this position throughout the drill.
Thrust arms upward & extend the legs so the body moves explosively upward.
The athlete should switch his legs quickly in the air so when he lands, he’s in the opposite leg position than when he started in.
Plyometric Drills – Body Weight: Speed Skater
Begin in same position as lateral jump.
Cock arms over to the right side.
Explosively extend the knee, hip, ankle, & trunk while simultaneously thrusting arms to the left side.
Laterally jump from left leg to right leg.
Land on right leg, dropping into same position the drill began in, & then repeat the action back & forth.
Plyometric Drills – Body Weight: Plyometric Push- Up
Begin in push-up position.
If the athlete isn’t strong enough to do a regular push-up, the modified “knees on ground” position may be assumed.
Drill is preformed like a push-up, except athlete comes up, extending arms, explosively, trying to leave the ground.
Some coaches will have the athlete clap hands in the air.
This exercise is difficult for athletes that have insufficient upper body strength.
Plyometric Drills – Hurdle Drills
These drills should emphasize power and should be short in nature so ideally 6 hurdles will be sufficient.
Develop various skills for athletes
Hopping drills:
Provide stimulus that help athlete jump higher, farther, & quicker
Can be performed for speed or height
Speed hopping Drills:
Work on decreasing amortization time, help explosive leg turnover
Height/Distance Jump Drills:
Work on explosive strength in hip extensors & flexors
Plyometric Drills – Hurdle Drills
LINEAR HURDLE HOP FOR HEIGHT or LINEAR HURDLE HOP FOR SPEED
Set hurdles in straight line.
Hop over hurdles, jumping as high as possible, taking off & landing on 2 feet.
Focus on maximizing height & pulling knees up during the jump.
Option for this drill: complete lateral hurdle hops for height
Set up hurdles in a straight line.
Hop over hurdles, sideways, jumping as high as possible, taking off & landing on 2 feet.
Focus on maximizing height & pulling knees up during the jump.
Plyometric Drills – Hurdle Drills
SINGLE-LEG LINEAR HURDLE HOP FOR SPEED
Perform drill the same as the linear hurdle hop for speed, but hop on one leg.
After completing the drill on one leg, repeat it on the other,.
Option is to perform this drill the same as the lateral hurdle hop for speed, but hop on one leg.
After completing the drill on one leg repeat it on the other.
Plyometric Drills – Hurdle Drills
HURDLES BACKWARD
Place series of hurdles 2ft from each other in straight line.
Stand with your back to the hurdles & jump backward over each one by extending the ankles & driving the knees & hips up.
Explosively swing arms upward.
Focus on decreasing time on the ground between hurdles.
Keep weight balanced over the front of the feet, waist slightly bent, shoulders facing forward, & head up.
Land on the balls of the feet, with the knees bent.
HURDLES DIAGONAL
Place hurdles in zig-zag pattern.
Place first hurdle & the next at a 90° angle to the following one.
Follow this pattern, place the remaining hurdles (6-8)
Begin by jumping forward extending knees, hips, & ankles.
Immediately upon landing, jump over the next hurdle.
Repeat this process for the remaining hurdles.
Focus on decreasing time on the ground between hurdles.
Keep weight balanced over the front of the feet, waist slightly bent, shoulders facing forward, & head up.
Land on balls of the feet, with knees bent.
Plyometric Drills - Hurdle Drills: Hurdles Diagonal
Plyometric Drills - Hurdle Drills: 90° Hurdles
Place series of hurdles 2ft from each other in a straight line.
Jump forward over first hurdle, while in midair make a half turn to the left.
On next jump, make a half turn back to the center.
Over the third hurdle make a half turn toward the right.
Next jump will be a half turn back to the center.
Repeat this process over the series of hurdles.
Medicine Ball Training
Advantages:
Add variety to stale training routines
Come in a variety of shapes, sizes, & weights
Made with handles & ropes for gripping
Serves many purposes
Heavier ball = Strength-speed or Power Sports/Activities
Med. Ball training mimics sports movement directly transfers to sport improvement
Medicine Ball Training
Effective way to build explosive power & muscular endurance
Can be used to develop speed with light weight ball
Can be used to develop power by using heavier balls with explosive movements
Important to learn proper technique
Do NOT perform single-arm-over-head throws (football) risk of injury
Improving endurance through med ball training:
rest between sets & exercise or…
number of repetitions or both
Medicine Ball Throws
Two-Hand Twist Toss
V-Up
Seated Trunk Rotation
Sit Up Toss
Twisting Sit Up Toss
Lying Power Drop
Two-Hand Overhead Throw
Axe Chop
Ancient Log Throw
Medicine Ball Throws
Two-Hand Twist Toss
V-Ups
Medicine Ball Throws
Seated Trunk Rotation
Sit-Up Toss
Medicine Ball Throws
Two-Hand Overhead Throw
Axe Chop
Medicine Ball Throws
Ancient Log Throw
Lower Body Power Drills
Designed around body-weight activities & improve power in jumping
basketball & volleyball
Power developed helps overall hip power that will help most other athletes.
When using a box for plyometrics select height between 12-24 inches.
Skilled athletes, 12-18 inches
Jump onto box
Depth jumps
Drills can be modified to include resistive tubing & med balls.
Body-weight plyometrics are best for athletes that fall into the speed-strength or explosive power categories.
Lower Body Power Drills – Depth Jumps
video
Complex Training
Complexes are a series of exercise performed in quick succession.
Used to improve conditioning or build explosive power.
Dumbbell & body-weight complexes use relatively light weights
Fit into speed-strength continuum somewhere between strength-speed & power
To build power-explosively perform 2-3 reps of each exercise.
| Complex | Exercise |
| Dumbbell Complex I | Upright row High-pull snatch Squat push press Bent-over row Power snatch |
| Dumbbell Complex II | Upright row High-pull snatch Squat & Press Good morning Bent-over row |
| Dumbbell Complex III | Biceps curl Upright row Bent-over row High-pull snatch Squat push press |
| Plyometric-Dumbbell Complex | Squats Vertical jumps Split-lunge jumps Split jerk Clean to press |
