Exam 4 The Final Flashcards
Stretch- shortening cycles (SSC)
a Model that explains the energy-storing capabilities of the series elastic component and stimulation of the stretch reflex that facilitate a maximal increase in muscle recruitment over a minimal amount of time
Series elastic component (SEC)
elastic structures in series with the contractile component that can store energy like a spring after being forcibly stretched
SSC Stages
phase 1 - eccentric
phase 2- amortization
phase 3- concentric
Phase 1 - eccentric
stretch of the agonist muscle
- elastic energy is stored
- muscle spindles are stimulated
- signal is sent to spinal cord
phase 2- amortization
pause between phases 1 and 3
- nerves synapse (meet) in spinal cord
- signal is sent to stretched muscles
phase 3- concentric
shortening of agonist muscle fiber
- elastic energy is released from the SEC
- stretched muscle is stimulated by nerve
Series elastic component (SEC)
primarily involves the tendon but also series with the contractile component that can store energy like a spring after being forcibly stretched
plyometric exercise
a quick, powerful movement preceded by a pre-stretch (countermovement ) and involving the stretch-shortening cycle (SSC)
Purpose of plyometric exercise
to used the stretch reflex and natural elasti components of muscle and tendon to increase the power of subsequent movements
Speed:
ability to achieve high velocity
To development involves several componets
-exploitation of SSC
-development of f via ↑ muscle f production
-technique
-stride frequency and stride length
Plyometric exercise
exploits 2 components of the stretch - shortening cycle (SSC)
1 mechanical
2 neurophsiological
mechanical
Plyometric exercise
- as the SEC lengthens, elastic energy is stored
- if a concentric muscle action is performed immediately after the eccentric action, the stored energy is released and contributes to force production
- if the transition phase is too long, the stored energy is lost as heat
Neurophysiological
Plyometric exercise
- involves potentiality of the concentric muscle action by used of the stretch reflex
- muscle spindles sensitive to rate and magnitude of stretch
- a quick stretch of high magnitude results in a reflexive muscle action
- if the concentric action does not immediate follow the stretch, the potentiating ability is negated
What is it used for
Plyometric exercise
- to develop explosiveness
- starting power
- power (perhaps also joint stiffness)
- high-magnitude
- short-duration eccentric loading
what to consider
Plyometric exercise
This are all really important to considere
- age
- experience
- current training level
- injury history
- physical testing results
- training goals
- both upper and lower body are involved
Injury
Plyometric exercise
- intensity, volume, frequency, recovery should be appropriate
- ideally, plyometric training should take place when individual is freshest and most rested
- general and specific warmup should take place prior to PE
- assessment of jumping and landing biomechanic
Injury number 2
Plyometric exercise
- balance, proprioception, speed, strenght
- landing surface should be nonslip and posses shock- absorbing properties but not so much that the amortization phase becomes significantly lengthened
- shoes should have good ankle and arch support, good lateral stability , and a wide, nonslip sole
- do the goals of the individual warrant plyometric training
- some jobs and sports
Speed-strength
Speed Training
application of maximum force at high velocitie
Speed-endurance
speed training
ability to maintain running speed over an extended duration ( usually > 6 sec)
speed training
speed is ultimately dependent on energy, muscle force, form/ technique, stride frequency, and stride length
Technique
speed training
this is significant effect on speed expression
-maximizing sprinting apeed depends on a combination of optimal body posture, leg action, arm action
body weight
speed training
flat grade sprinting (often interval), form drills
sprint-assisted training
Speed training
- downgrade sprinting (3-7 dergges), hight speed towing, high speed treadmill
- should not ↑ speed by more than 10% of the indiidual max speed
resisted spriniting
Speed training
- upgrade sprinting, sled pulling (pushing), elastic tubing, parachute
- too much external resistance will become counterproductive to speed development
Volume
Quality of effort is crucial
speed training
volume does not need to be particularly high if quality of effort is high
- high bolume with low quality may be essentially useless
- -conditioning, work capacity and mental toughness training have different goals
- –be sure to know what the goal of the training is
Spped
Quality of effort is crucial
speed training
-speed training should take place when individual is freshest and most rested
-does not always happen that way for athletes whose sport is not running
Example on on the handout
high levels Strenght/power
will only help so much in the absence of optimal technique
- some will naturally have good technique, most will probably require some coaching
high speed running
requires high power production capabilities
- person can be strong an not powerful BUT a person ca NOT be powerful without also being strong
- –optimal development of sprinting speed probably requires a combination of running training and strength training and power training
straight line and Lateral movement
lateral movement involves ability at accelerate, decelerate, change direction, accelerate
- -in sports this occurs at high speeds and under high forces (agility training )
- *speed training and plyometric training in the same session (or even the same day) might be problematic
Plyometrics
Joes PP
yuri verkhoshanky in russia in ealry 1960
- shock method
- father of plyometrics
Plyometric
.
pilometric
.
power metric
.
Injury considerations
Joes PP
- injury risk is elevated with these types of exerise
- reaseach is less clear
- guideline exist for this such as you should be able to lift a certion amount first
- most are from overused injries or injury due to poor form (quanlity is better than qunaityt)
Who should preform plyometrics
Joes PP
- perform a need analysis
- -peeps who need to be explosive
- sports and jobs
“triain the way you play”
– old peopel can do this too
Benfit risk ratio NEEDS to be looked at
contrast load
Joes PP
-alternating sets of strenght with power
Strength
-load- 85% 1RM
Power
- load- 30-45% 1RM
- have to have light weight and fast to work
Plyometrics
Joes PP
the lower body is jumping type motions
- Upper body can be used too
- – more with explosive push ups
- this can really hurt the wrist and shoulders
- work with medican balls is the best
Esploiting the SSc
- the time btwn the concetric and eccentric need to be short
- long SSC- >250 ms
- short SSC
Post activation potentiation
Joes PP
.
Post activation potentiation part 2
Joes PP
- ↑ in throw height following tradtional heavy load barbell lift
- 3 sets of 3 reps of 80% 1 RM in bench press was performed first
- after 10 min of rest, throws were performed & by 38-40% this was a huge diff
muscle - tendon unit
Joes PP
→// elastic compenent (pec) -epimysium, perimysion, endomysion, sarcolmmal →series elastic component (sec) -tendon cross bridges, myoflimanet , →contractile component (cc) -actin, myosin, cross bridges
Contribution of SEC
Joes PP
-estimated that elastic energy may account for 20-30% of the diff btwn a countermovement & noncountermov. jump
Plyometrics part 3
Joes PP
- used to ↑ speed, power, quikness
- typically involved something (movement ) that invovles a release
- also called stretch - shortening cycle training
- exploitation of the ssc lead to ↑ force production during a con. phase.
Back ground
Musculoskeletal injuries
- risk of injury with any physical activity, sport, E
- range from (serious or minor)
identifying risk of injury
Back ground
Musculoskeletal injuries
1 personal/medical history
2 known association w/ certain activities
–lower back injuries in lifting
– tendinitis in repetitive movement
–shin splints in running
3 injury- prone people
4 idea of pre habilitation has gained much attention in recent years
spontaneous?
Back ground
Musculoskeletal injuries
some injuries appear to be spontaneous with no warning signs! but many have warning signs but you just dont recongnized them
common ingredients for MS injuries
Back ground
Musculoskeletal injuries
-bad techniqu (fatigue, inflexibility, miseducation) -excessive overload (stress-strain-failure relationship) -chronic overuse -ignoring warning signs
Freak injury
Back ground
Musculoskeletal injuries
usuall very rae and upreditable but can have catastrophic consequences
- the guy that was paralyed during a lift ( crossfit) video in class
Injury types ( acute )
1 strains
2 sprains
Strains
Injury types
1 tears/ ruptures avulsion involving muscle and bone
2 muscle tears graded by degree of damage
3 muscle tear can present with a significant contusion/ hematoma
muscle tears graded by a degree of damage
Strains
Injury types
1st- partial tear; strong but painful muscle activity
2nd- partial tear; weak and painful muscle activity
3rd- complete tear; very weak and painless muscle activity
Sprains
injury types
-ligaments trauma 1 blunt force or other trauma 2 intervertebral disc herniation 3 skeletal fracture 4 other --dislocation --subluxation
dislocation
complete displacement of joint surfaces
subluxation
partial displacement of joint surfaces
Injury types (chronic)
- overuse
- intervertebral disc bulging
overuse examples
injury types
tendon: tendiopathies
bone: skeletal microdamage- stress fractures
overuse ingredients
injury types
1 poor program design 2 suboptimal training surfaces 3 faulty biomechanices/ technique 4 insufficient motor control 5 ↓ flexibility 6 skeletal malignant
Intervertebral disc anatomy
injury types
nucleus pulposus- the middle portion
annulus fibrosis-the outer parr
commonly injured joints/ areas
1 strength training: knee, shoulder, low back , wrist, elbow, neck
2 endurance training: knee, foot, ankle, lower leg, hip
Management
1 acute injuries
2 chronic overuse injuries
3 professionals involved
acute injuries
management
1 know emergency response and 1st aid procedures
2 direct injured person to appropriate medical personnel
3 soft tissue injuries: rice, heat/cold application
chronic overuse injuries
management
1 avoid aggravating activity/ movement
2 analgesic and anti- inflammatory medication
–masks the symptoms often does not fix the problem
–underlying problem can get worse becuz body normal means of letting person know there isa problem have been impaired so the damage continues
professionals involved
management
1 athletic trainers 2 physical therapists 3orthopods 4 psychologist 5 nutritionists 6 other
Athletic trainers
professionals involved
management
usually involved in acute, on the field management in athletic settings
- may also be involved in rehabilitation
physical therapist
professionals involved
management
usually involved in rehabilitation setting
orthopods
professionals involved
management
can be involved in any aspect of injury management
- also responsible for advanced treatment (surgery, mediction)