Training adaptations - nerves Flashcards
When the level of force development increases what happens to the motor cortex activity?
It increases
Increases motor cortex activity does what to the neural drive to agonist muscle as well as firing rate?
Increases neural drive and enhances firing rate
What threshold motor units are recruited first?
Low-threshold
Do low-threshold or high-threshold motor units have lower force capabilities?
Low-threshold
In advanced lifters, what adaptations occur to the CNS in order to help with greater production of power or speed?
Able to recruit some motor units not in consecutive order, recruiting larger ones first.
What is postactivation potentiation?
Performing similar type movement at max or near maximal contraction so it is easier to recruit type II motor units
What does PAP do to rate of force development?
Speeds it up, quicker recruitment of fibres
PAP increases motor-neuron pool excitability, what does this do to the motor unit synchronization and acetylcholine release?
Bettwen synchronization and increased release of acherylcholine.
Why does postactivation potentiation help cross bridge formation and turnover?
Increases Ca2+ released from the sarcoplasmic reticulum which activates MLC kinase. More ATP broken down at the actin-myosin complex.
What is the optimal recovery from PAP?
7-10 mins
What happens if you leave rest after PAP more than 10 mins?
The effect is reduced
What % 1RM should be performed for PAP?
90%
What type of sports may benefit from PAP?
Single explosive events e.g sprinters, gymnasts
What happens to the acetylcholine receptors within the end plate region as a change from training?
Greater dispersion of these
What happens to the synapses and the nerve terminal branching as an adaptation of training?
More dispersed, irregularly shaped synapses and a greater total length of nerve terminal branching
what % improvement of the reflex response from the muscle spindles does anaerobic training enhance?
20-50%
Studies have shown strength and power training increases EMG activity by up to what %?
75%
What is rate of force development?
Change in force over time
Is RFD quicker in ballistic or isometric contractions?
Ballistic
When is peak force usually achieved in?
500ms
Why would it help performance if peak force could be achieved quicker?
Because many sports movements take less time than 500ms
What happens in the early phase (<100ms) of RFD?
More fibres are recruited to generate force
What happens in the late phase (>200ms) of RFD?
More nerve pulses are sent to each muscle fibre and generation of peak force
What phase of RFD does max strength have a better correlation with?
The late phase
