Plyometric training

Question 1

Plyometric training is a ….. followed by a …… ……..

Answer 1

Pre-stretch

Forceful contraction

Question 2

What are the 3 mechanical processes of plyometrics?

Answer 2

Elongation of SEC (series elastic component) —–Storage of elastic energy —-Release of elastic energy

Question 3

What does the rapid stretch cause?

Answer 3

An increase in elastic energy in tendons and muscles

Question 4

When concentric action is followed, what happens to the stored elastic energy?

Answer 4

released

Question 5

If the stretch is not followed by a contraction, what happens to the stored elastic energy?

Answer 5

Lost as heat

Question 6

What does the PEC (parallel elastic component) do?

Answer 6

Exerts a passive force with unstimulated muscle stretch

Question 7

Give an example of a PEC

Answer 7

Epimysium, perimysium

Question 8

What does the CC (contractile component) do?

Answer 8

Primary source of muscle force during concentric action

Question 9

Give an example of a CC

Answer 9

Actin and myosin

Question 10

What does the SEC (series elastic component) do?

Answer 10

Acts as a spring and stores energy that increases force production

Question 11

Give and example of SEC

Answer 11

Tendons

Question 12

What muscular component detects the stretch?

Answer 12

Muscle spindles

Question 13

How is the signal transported to the spinal cord?

Answer 13

Via type 1a nerve fibres

Question 14

What does the signal synapse with in the spinal cord?

Answer 14

alpha motor neurons

Question 15

Where does the impulse go after the spinal cord and what happens here?

Answer 15

To the agonist extrafusal fibres, causing a reflexive muscle action.

Question 16

What does the neurophysiological model involve?

Answer 16

potentiation

Question 17

Define stretch reflex

Answer 17

The body’s involuntary response to an external stimulus that stretches the muscles.

Question 18

What does the neurophysiological model say happens to the muscles contractile components?

Answer 18

Change in the force-velocity characteristics caused by the stretch of the concentric muscle action.

Question 19

What does the stretch shortening cycle employ to facilitate maximal increase in muscle recruitment over minimal amount of time?

Answer 19

Both the energy storage of the SEC and stimulation of the stretch reflex.

Question 20

What is vital to muscle recruitment and activity resulting from the stretch shortening cycle?

Answer 20

A fast rate of musculotendinous stretch.

Question 21

What are the 3 stages of the stretch-shortening cycle?

Answer 21

Eccentric
Amortization
Concentric

Question 22

What happens in the eccentric phase?

Answer 22

stretch agonist muscle, energy stored in SSC, muscle spindles activated

Question 23

What happens in the amortization phase?

Answer 23

Pause, Type 1a afferent nerves synapse with alpha motor neurons and these transmit signal to agonist muscle.

Question 24

What happens in the concentric phase?

Answer 24

Shortening of the agonist muscle, energy released from SEC, alpha neuron stimulate agonist muscle.

Question 25

What is another term for the amortization phase?

Answer 25

electromechanical delay

Question 26

Define electromechanical delay

Answer 26

The delay time of the afferent and efferent nerve transmission

Question 27

If the EMD is not kept short what happens?

Answer 27

Energy is lost as heat

Question 28

What is the delay time of nerve transmission related to?

Answer 28

The distance of the muscle to the spinal cord

Question 29

Plyometric training increases what performance factors?

Answer 29

``` Jump height and power Sprint speed Running economy Kicking speed Throw velocity Max strength Sport specific performance Muscle hypertrophy ```

Question 30

What effects does plyometrics have on speed and multidirectional speed?

Answer 30

``` Improves acceleration Improves ground reaction force into horizontal propulsion Decreases ground contact time Reduces deceleration Enhances sprint technique ```

Question 31

How does plyometrics enhance rate of force production?

Answer 31

enhances muscle spindle activity, enhances elasticity of SEC.

Question 32

TRUE or FALSE. Plyometrics increases firing frequency, synchronization and motor unit recruitment?

Answer 32

TRUE

Question 33

Plyometrics desensitizes GTO activity, what effect does this have on the muscle inhibition stimulation threshold?

Answer 33

Increases it

Question 34

Plyometrics increases fibre type transformation, what transformation is made?

Answer 34

Type IIx to type IIa

Question 35

Plyometric training can be used to cause ........potentiation

Answer 35

Post-activation

Question 36

What is the ground contact time of fast plyometrics?

Answer 36

100-250ms

Question 37

Greater neural training effects with fast plyometrics because of what reason?

Answer 37

Greater neural activation and faster shortening velocity

Question 38

What does fast plyometrics increase in type II fibres?

Answer 38

Peak power

Question 39

What does fast plyometrics increase in the tendon?

Answer 39

CSA

Question 40

What is slow plyometrics?

Answer 40

slower to complete each rep, hence slow SSC

Question 41

What muscle spindle does fast plyometrics use?

Answer 41

Both stretch and muscle spindle

Question 42

What muscle spindle does slow plyometrics use?

Answer 42

Primarily muscle spindle

Question 43

As intensity increases, volume should ....

Answer 43

Decrease

Question 44

How frequent should plyo sessions be performed per week?

Answer 44

2-4 times

Question 45

How is volume assessed in lower body drills and upper body drills?

Answer 45

lower body = contacts per workout | Upper body = number of throws or catches

Question 46

State the volume (contacts per session) for beginners, intermediate and advanced

Answer 46

``` Beginners = 80 to 100 Intermediate = 100 to 120 Advanced = 120 to 140 ```

Question 47

How much recovery between reps?

Answer 47

5-10s

Question 48

How much recovery between sets?

Answer 48

2-3 mins