Chapter 18 - Plyometric (Reactive) Training Concepts

Question 1

What is plyometric (reactive) training

Answer 1

Exercises that generate quick, powerful movements involving an explosive concentric muscle contraction preceded by eccentric muscle action.

Primarily revolves around exercise that uses explosive movements such as bouncing, hopping, or jumping to develop muscular power.

Question 2

What is rate of force production?

Answer 2

Ability of muscles to exert maximal force output in a minimal amount of time.

Question 3

True or False:
Clients must possess adequate core strength, joint stability, and range of motion and have the ability to balance efficiently before performing any plyometric exercises.

Answer 3

True.

Question 4

Describe the integrated performance paradigm.

Answer 4

To move with efficiency, forces must be dampened (eccentrically), stabilized (isometrically), and then accelerated (concentrically).
(Think of the movements/process of jumping).

Question 5

What is the stretch-shortening cycle?

Answer 5

• An active stretch (eccentric contraction) of a muscle followed by an immediate shortening (concentric contraction) of that same muscle
• Require neuromuscular system to react quickly and efficiently after an eccentric muscle action to produce a concentric contraction and impart necessary force (acceleration) in the appropriate direction.

(Since the length of the tendon increases due to the active stretch phase, if the series elastic component acts as a spring, it would therefore be storing more potential energy. This energy would be released as the tendon shortened. Thus, the recoil of the tendon during the shortening phase of the movement would result in a more efficient movement than one in which no energy had been stored)

Question 6

Describe the basics of the eccentric phase.

Answer 6

Eccentric phase: deceleration, loading, yielding, counter movement, cocking phase.
- Increase muscle spindle activity by pre-stretching the muscles before activation.
- Potential energy is stored in the elastic component of the muscle during this loading phase much like stretching a rubber band.

Question 7

Describe the basics of the amortization phase.

Answer 7

• Also known as the transition phase
• The electromechanical delay between eccentric and concentric contraction during which that muscle must switch from overcoming force to imparting force in the intended direction (rapid switch = more powerful response)
• Involves dynamic stabilization and is the time between the end of the eccentric muscle action (the loading or deceleration phase) and the initiation of the concentric contraction (the unloading or force production phase)

Question 8

Describe the basics of the concentric phase.

Answer 8

• Also known as the unloading phase
• Occurs immediately after the amortization phase
  -involved a concentric contraction resulting in enhanced muscular performance after the eccentric phase of muscle contraction
• Synonymous with releasing a rubber band after it was stretched

Question 9

Why is plyometric training important?

Answer 9

1. Enhances excitability, sensitivity, and reactivity of the neuromuscular system
2. Increases the rate of force production (power)
3. Increases motor unit recruitment
4. Increases firing frequency (rate coding)
5. Increases motor unit synchronization

Question 10

What is the ultimate goal of plyometric training?

Answer 10

Decreasing the reaction time of the muscle action spectrum (result = increase speed of movement in the individual).

Question 11

Describe the design parameters for developing a plyometric training program.

Answer 11

1. Systematic
2. Progressive
3. Client must exhibit proper levels of total body strength, core strength, and balance before progressing into plyometric training
4. Client must wear supportive shoes and perform exercises on a proper training surface such as grass field, basketball court, or track

Question 12

Describe the parameters of a plyometric stabilization exercise.

Answer 12

1. Involve little joint motion
2. Designed to establish optimal landing mechanics, postural alignment, and reactive neuromuscular efficiency (coordination during dynamic movement).
3. Hold “Landing Position” (stabilize) for 3-5 seconds (during this time, the individual should make any adjustments necessary to correct faulty postures before repeating the exercise.

Question 13

Give some examples of plyometric stabilization exercises.

Answer 13

1. Squat jump (with stabilization)
2. Box jump-up (with stabilization)
3. Box jump-down (with stabilization)
4. Multiplanar jump (with stabilization)

Question 14

Describe the parameters of a plyometric strength exercise.

Answer 14

1. Involve more dynamic eccentric and concentric movement through a full range of motion
2. The specificity, speed, and neural demand may also be progressed at this level
3. Exercises tend to improve dynamic joint stabilization, eccentric strength, rate of force production, and neuromuscular efficiency of the entire HMS
4. Exercises performed in a repetitive fashion (spending relatively short time on the ground before repeating the drill)

Question 15

Give some examples of plyometric strength exercises.

Answer 15

1. Squat jump
2. Tuck jump
3. Butt kick
4. Power step-up

Question 16

Describe the parameters of a plyometric power exercise.

Answer 16

1. Involve the entire muscle action spectrum and contraction-velocity spectrum used during integrated, functional movements
2. Designed to further improve the rate of force production, eccentric strength, reactive strength, reactive joint stabilization, dynamic neuromuscular efficiency and optimal force production.
3. Exercises performed as fast and as explosives as possible (safely).

Question 17

Give some examples of plyometric power exercises.

Answer 17

1. Ice Skaters (skater jumps)
2. Single-Leg Power Step-Up
3. Proprioceptively Plyometrics