EXPH 2190: Pylometrics & Jump training

pylometrics =

activities that enable a muscle to reach maximal force in the shortest possible time

pylometrics uses the

stretch-shortening cycle

how does resistance training utilization of SSC different from pylometrics use of the SSC

resistance training allows for training of the components of the SSC whereas pylometrics are an attempt to train SSC to elicit activity specific speed/power requirements

true/false: pylometric training improves the force-velocity relationship of muscle by increasing power

true

what are the two models of the SSC

mechanical and neurophysiological

what are the 3 components of the mechanical ssc model

contractile component, series elastic component, parallel elastic component

true/false: the contractile component of the mechanical SSC model is the tendon

false, it is the active component which is the muscle

what is the series elastic component of the mechanical SSC model

the tendon

what is the parallel elastic component of the mechanical ssc model

passive tension —> connective tissues

what component is responsible for performing the majority of the work in the SSC

the series elastic component

true/false: tendons can store energy if muscle produces high force

true

what time of energy does the series elastic component store

elastic energy

the series elastic component allows for the muscle to operate near

maximal force output which is more efficient

what happens if the amortization or eccentric phase is too long

the stored elastic energy is lost as heat

true/false: parallel elastic components exert passive force with stimulated muscle stretch

false, they exert force passively with unstimulated muscle stretch

what are the types of parallel elastic components

epimysium, perimysium, endomysium, and sarcolemma

what does the difference between fascicle and muscle-tendon behavior suggest

it suggests that the neural input in fast SSC exercises minimizes the length changes in muscle fascicle and enables storage and recoil of energy from elastic components

components of the neurophysiological SSC model

potentiation, stretch-reflex, muscle spindle, golgi tendon organ

true/false: the neurophysiological ssc model surrounds active tension

false, it is passive tension

what is potentiation

positive change in force-velocity characteristics of the muscles contractile components when stretched

the stretch reflex arises from?

muscle spindle activation

where are muscle spindles located

within the muscle

what are muscle spindles

proprioceptive muscle organs that are sensitive to stretch

true/false: when stretch is sensed by muscle spindles, the reflex excites the tendon

false, the reflex excites muscle activation and the motor unit fires

the more stretch there is, the greater the…

reflex or muscle spindle activation is

what is the golgi tendon organ

proprioceptor in tendon that is sensitive to tension in the muscle (stretch)

true/false: the golgi tendon organ has an inhibitory effect

true, protects against injury from excessive force

how are the muscle spindle and GTO activations different?

muscle spindles are located within muscle and detect changes in stretch and excites the muscle, GTOs are located in the tendon and has an inhibitory effect to prevent injury

true/false: heavy resistance training may increase motor cortex ability to decrease GTO sensitivity

true

during what type of muscle activation is muscular force output greater while doing SSC activities

concentric activation

why is muscular force output during SSC activities greater during concentric activations

higher stretch rate results in greater muscle recruitment during the concentric phase

why is the muscle activation before initial contact and during initial impact most important

because majority of the force generated is from pre-activation (eccentric-stretch phase) into concentric force

what is one exercise we could use to train the eccentric-stretch phase of the SSC model

drop jumps

with training, contact time was ___________ and ground reaction forces __________

decrease, increased

during braking: muscle activity _________ in the plantar flexors and __________ in dorsiflexors, and fascicle behavior of the gastroc was __________

increased, decreased, unchanged

during propulsion: muscle activity of the plantar flexors and shortening velocity of the gastroc _________ while shortening velocity of the tendon _________

decreased, increased

what mechanisms play a role in improving SSC exercise?

1.) optimization of muscle-tendon behavior of the agonists and neuromuscular activity during SSC exercise and increase in tendon stiffness

2.) decrease in neuromuscular activity of antagonists during a counter movement

ways to optimize force with pylometrics

1. high levels of preactivation (neural)

2. fast stretch to stimulate stretch reflex (neural)

3. strong tendons to recoil elastic energy (tendons)

4. fast shortening velocities to optimize transfer of force developed during loading (muscles)

what are some lower body pylometric exercises?

1. snap downs (ecc)

2. ground based jumps in place (con)

3. landings (ecc)

4. box jumps (con)

5. drop jumps (ecc, amort, con)

what are some upper body pylometrics?

pitching softball/baseball

tennis

shot put, discus, javelin

throwing children

explosive push up variations

MB throws and catches

why is trunk plyometrics important?

provides anterior core, low back, oblique work and is important to train quick action

what are some good trunk plyometrics?

rotational MB throws, sit up throws

what training frequency is recommended for plyometric program designs

48-72 hours recommended between sessions, but ultimately depends on training status and recovery ability

true/false: exercise order depends on the focus of the day

true

how could exercise order follow a graded progression of intensity for plyometrics?

1. eccentric focus

2. concentric focus

3. repeated combined SSC focus

4. application to sport movement

naming plyos:

jump =

hop =

bound =

jump = 2 leg takeoff, 2 leg land

hop = single leg takeoff, single leg land

bound = single leg takeoff, opposite leg land

what factors can be assessed with intensity?

stance (bilateral —> unilateral)

intent (0-100%)

height/distance (directionality, amount of impact force)

stiffness (full ROM or less ROM)

when are joint mechanics at the ankle best?

during two foot ankle hop and tuck jumps

when are joint mechanics at the hip best?

during repeated squat jumps or double leg hop

true/false: joint specific plyometric intensity during landing also differs between exercises and among joints

true

what exercise is best for ankle mechanics during landing?

box jump up

what exercise is best for hip mechanics during landing?

tuck jump

volume is plyometrics is typically described as?

number of foot contacts or distance

what is complex training?

high intensity resistance training followed by plyometrics

example of complex training

goblet RFE split squat —> MB split stance snap down —→ SL box jump, double leg land 12'“

what is the suggested load for resistance training plyometric combos?

30% 1RM

what is french contrast?

A training method that involves alternating between strength and power exercises, typically using a combination of heavy resistance and explosive movements.

example of french contrast set up

1. resisted movement of choice

2. unresisted plyometric

3. resisted plyometric

4. assisted plyometric