1 / 63

Plyometrics: Reactive/Power Training

Plyometrics: Reactive/Power Training. Reactive Training. Reactive training: A quick powerful movement involving an eccentric contraction, followed immediately by an explosive concentric contraction This is accomplished through plyometric exercises

elden
Download Presentation

Plyometrics: Reactive/Power Training

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. Plyometrics:Reactive/Power Training

  2. Reactive Training • Reactive training: • A quick powerful movement involving an eccentric contraction, followed immediately by an explosive concentric contraction • This is accomplished through plyometric exercises • Plyometrics are activities that enable a muscle to reach maximal force in the shortest amount of time possible. This is called the rate of force production

  3. Plyometrics • This type of training involves powerful muscular contractions in response to a rapid stretching of the involved musculature. • These powerful contractions are not a pure muscular event; they have an extremely high degree of central nervous system involvement. • Reactive training improves neuromuscular efficiency

  4. Plyometrics • Plyometric exercises can be incorporated once a client has achieved proper core and balance stabilization • Ultimate goal of plyometrics is to increase the reaction time of:

  5. Plyometrics • A good example of this is watching any basketball player jump. • They jump higher when they can take a few steps before the jump. • The reason for this is that the few steps create momentum. • This momentum is used to create a bigger and faster “load” on the leg plant prior to jumping. • The response to this greater load is a greater contraction by the legs and a higher jump height. • The same phenomenon exists with all explosive actions.

  6. Mechanical Model of Plyometric Exercise • Elastic energy is stored following a rapid stretch, then released during a concentric muscle action increasing total force production • The mechanical model presents the function of the musculotendionous unit as a relationship between three mechanical components

  7. Mechanical Model of the Muscle • Three elements compose the mechanical model of the muscle influencing its mechanical behavior and effecting contraction:

  8. Contractile Component • The contractile component represents the muscle fibers, which are the active part of the muscle and are competent to produce tension

  9. Parallel Elastic Component • The parallel elastic component represents the connective tissue surrounding each muscle fiber, groups of fibers and thewhole of the muscle.

  10. Series Elastic Component • The series elastic element refers mainly to the tendons of the muscle which are placed "in series" with the contractile and parallel elastic elements. • When the muscle-tendon unit is stretched during an eccentric contraction, the SEC acts as a spring and is lengthened, storing elastic energy • If the muscle immediately begins a concentric contraction, the stored energy is released

  11. Neurophysiological Model of Plyometric Exercise • This model represents the • Plyometric exercise is composed primarily of • Muscle spindles are sensitive to the rate and magnitude of a ; when a quick stretch is detected muscle activity increases

  12. Neurophysiological Model of Plyometric Exercise • Stretch Reflex: • The body’s involuntary response to an external stimulus that stretches the muscles • When muscle spindles are stimulated, the stretch reflex is stimulated, sending input to the spinal cord via nerve fibers • The nerve impulses travel to the agonist muscle fibers, causing a reflexive muscle action

  13. Stretch Shortening Cycle (SSC) • The stretch-shortening cycle (SSC) employs both the energy storage of the SEC and stimulation of the stretch reflex to facilitate maximal increase in muscle recruitment over a minimal amount of time • A fast rate of musculotendinous stretch is vital to muscle recruitment and activity resulting from the SSC

  14. Stretch-Shortening Cycle • The SSC Model involves three phases:

  15. Phase I: Eccentric Phase • Stretch of the agonist muscle • Preloading the agonist muscle group • The SEC (muscle-tendon unit) stores elastic energy • Muscle spindles are stimulated • Signal is sent to the spinal cord • Example: A basketball jump shot • The person performs a half-squat before jumping up • The time from the beginning of the squat to the bottom of the movement is the eccentric phase

  16. Phase II: Amortization • Amortization or Transition Phase is the time between the eccentric and concentric phases • Pause between Eccentric to Concentric muscle actions • Spinal Cord begins to transmit signals to the agonist-stretched-muscle group • If the amortization phase lasts too long, the energy stored during the eccentric phase will be dissipated as heat • Example: Basketball jump shot • From the downward half-squat as soon as upward movement begins, amortization phase has ended

  17. Phase III: Concentric Phase • Shortening of agonist muscle fibers • Elastic energy is released from the SEC to increase force production • The stretched muscle is stimulated neurally • Example: Following the half-squat in the jump shot, the individual moves upward

  18. Explain the SSC with a Basketball Jump Shot Phase I: Phase II: Phase III:

  19. Stretch Shortening Cycle Basketball Jump Shot • Phase I: Eccentric Phase The agonist muscles (quadriceps) undergo a rapid stretch • Phase II: Amortization Phase There is a delay in the movement • Phase III: Concentric Phase The quadriceps acts concentrically to extend the knee, allowing the person to push off the ground

  20. Plyometric Program Design • Ideal when the goal is to improve muscular power • Power: The time rate of doing work • Force x distance/time • Force x velocity • Examples: police officers having to run quickly and change direction or jump over obstacles, firefighters, warehouse workers lifting boxes…

  21. Plyometric Program Design • Exercise Selection: • Safe • Done with supportive shoes • Performed on a proper training surface • Performed with proper supervision • Progressive: • Simple to complex • Known to unknown • Stable to unstable • Body weight to loaded • Activity specific

  22. Plyometric Program Design • Variables: • Plane of motion • Type of resistance • MB • Type of implements • Boxes • Cones • Hurdles • Muscle action (eccentric, isometric, concentric) • Speed of motion • Duration • Frequency

  23. Plyometric Program Design • Be systematic • Be progressive • A client must exhibit proper levels of core strength and balance before progressing into reactive training

  24. Age Considerations • Adolescents • Consider both physical and emotional maturity. • The primary goal is to develop neuromuscular control and anaerobic skills that will carry over into adult athletic participation. • Gradually progress from simple to complex • The recovery time between workouts should be a minimum of two to three days.

  25. Age Considerations • Older Adults: • Can perform plyometric exercises as long as modifications are made for orthopedic conditions and joint degeneration • The plyometric program should include no more than five low- to moderate-intensity exercises • The volume should be lower, that is, should include fewer total foot contacts than a standard plyometric training program • The recovery time between plyometric workouts should be three to four days

  26. Contraindicated Populations • Plyometric training may alter bone structure; spine height has been shown to decrease by up to 2 mm following a depth jumping program (high intensity) • Research has yet to determine the age at which one can participate in a plyometric training program

  27. Contraindicated Populations • Adolescents should be careful because of epiphyseal plate closures • Older adults should be careful because of osteoporosis • Clients who never participated in resistance training should be precluded • Plyometric training requires strength and muscle control

  28. Needs Analysis • Analyze needs of the client: • Age (safest over the age of 13) • Training experience and current level of training (more than three months of resistance training) • Injury history (no current injuries) • Fitness Evaluation: what are the client’s current abilities (beginner, intermediate, advanced)? • Training Goals: does the client want to improve a skill or a particular move (volley ball spike, tennis serve, baseball pitch…) or on the job activity

  29. Mode (Type) • Determined by the general body parts that are performing the given exercise • Example: • Depth Jump is a lower body plyometric exercise • MB Chest Pass is an upper body plyometric exercise

  30. Lower Body Plyometrics • Jumps-In-Place: • Squat jump and tuck jump • Standing Jumps: • Vertical jump and jumping over barriers • Multiple hops and jumps • Bounding and skipping • Box Jumps • Depth Jumps

  31. Squat Jump • Stand with feet shoulder-width apart • Draw naval in and activate gluteals • Jump up, extending arms overhead • Land softly, maintaining optimal alignment and repeat immediately

  32. Tuck Jumps • Stand with feet shoulder-width apart • Draw naval in and activate gluteals • Jump up, bringing knees to chest • Land softly, maintaining optimal alignment

  33. Box Jumps • Stand in front of a box or platform with feet shoulder-width apart • Draw in navel and activate gluteals • Using arms, jump up and land on top of box, keeping toes pointing straight ahead and knees over toes • Step off box

  34. Bounds • Jog into the start of the drill for forward momentum. • After a few feet, forcefully push off with the left foot and bring the leg forward. At same time drive your right arm forward. • Repeat with other leg and arm • This exercise is an exaggerated running motion focusing on foot push-off and air time

  35. Depth Jumps • Stand on a box or platform with feet shoulder-width apart • Draw in naval and activate gluteals • Using arms, jump off the box and land on floor, keeping toes pointing straight ahead and knees over toes

  36. Upper Body Plyometrics • Not used as often • MB Chest Pass • MB Slam • Two-Hand Overhead Throw • Single-Arm Throw • Depth Push-Up • Push-Up with a Clap • Power Drop

  37. Overhead Throw and Side Throw

  38. Overhead Back Toss • Stand with feet slightly wider than hip-width apart. • Have a partner or trainer stand approximately 10-15 yards behind you. • Grasp MB and lower body into a squat position. • Explode up extending the entire body and throwing medicine ball up and over the body. • The goal is to throw the ball behind you as far as you and generating most of the power in the legs.

  39. MB Slams • Stand with feet parallel, shoulder-width apart • Pull MB back behind head and forcefully throw ball down on the ground as hard as possible. • Catch the ball on the bounce from the ground and repeat according to prescribed repetitions

  40. Plyometric Push-Up • Get into a push-up position. • Lower yourself to the ground and then explosively push up so that your hands leave the ground. • Catch your fall with your hands and immediately lower yourself into a push-up again and repeat

  41. Intensity • Plyometric Intensity refers to the amount of stress placed on muscles, connective tissues, and joints • Factors affecting Intensity include: • : progress from double to single leg support places more stress on muscles, connective tissues, and joints • : greater speed increases intensity • : Raise the body’s center of gravity by increasing the height of the drill : Greater the individual’s weight more stress is placed on body. External weight can be added (vests)

  42. Intensity • Low Intensity: • Squat jump and vertical jump • Moderate Intensity: • Double leg tuck jump and split squat jump • High Intensity: • Depth jump and pike jump

  43. Frequency • Number of plyometric sessions per week • plyometric sessions per week

  44. Volume • Number of reps and sets performed during training sessions • Lower Body Plyometrics Volume: • Number of foot contacts per workout or expressed as distance • Upper Body Plyometrics Volume: • Number of throws or catches

  45. Lower Body Plyometrics Volume Guidelines

  46. Recovery • Recovery between sessions: • 48-72 hours between sessions • Recovery for depth jumps may consist of 5-10 seconds of rest between reps and 2-3 minutes between sets • Work to rest ration is 1:5 to 1:10 specific to the plyometric activity • Drills should not be thought of as cardiorespiratory conditioning exercises but as power training • Furthermore, drills for a given body area should not be performed two days in succession.

  47. Plyometric Length and Progression • Program Length • Currently, most programs range from 6 to 10 weeks; however, vertical jump height improves as quickly as four weeks after the start of a plyometric training program • Progression • Plyometrics is a form of resistance training and thus must follow the principles of progressive overload (the systematic increase in training frequency, volume, and intensity in various combinations).

More Related