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Flashcards in Chronic Adaptations to Strength Deck (23):

What is the difference between STR-Type RE and HYP-type RE?

STR-Type RE = high loads, low volume, low rest (central fatigue and neural adaptations)

HYP-Type RE = mod loads, high volume, short rest (peripheral fatigue and hypertrophic adaptations)


How does our body adapt from strength training?

Body adapts to new stimuli - if fibres are not recruited then they are not trained
Recruit smaller STF fibres before larger FTF
Super-compensation curve commonly used (fatigue enables us to make adaptations)


What are some of the different training methods in which we can follow?

Why is Isoinertial training good for strength?

Improvements in strength when completing Isoinertial, isokinetic and electrical stimulation training

Greater increase in isometric forces and improves functional performance


What factors affect adaptations from occurring?

Programme design, Gender, Training History and Age


What do strength and power adaptations both improve?

Jump and sprint performance

Power increases neural drive, force and RFD
Strength increases neural drive, RFD and thickness


What is the typical time course for adaptations occur?

What is the relationship between neural changes and muscular changes?

Neural changes - <6-8 weeks
Muscular changes = 9-12 weeks

As muscular increase neural decreases


What are the pros and cons of the research on adaptations?

Been criticised due to:
Techniques (EMG), types of training and test frequency

Literature against:
Shown to be muscular adaptations after 4 weeks and molecular pathways adapt after a few sessions


What is the difference between hypertrophy and hyperplasia?

Hypertrophy => increase muscle size - increases in CSA and thickness (Type II preferential)

Hyperplasia => longitudinal splitting of fibres (generally occurs alongside hypertrophy)


What is hypertrophy influenced by?

Training design, age, contraction type


What is the stimuli for hypertrophy?

1) Tension and muscle damage
2) mTOR signalling
3) Training intensity
4) Muscle activation


What is the affect of Blood Flow Restriction during resistance training?

At what loads is this actually beneficial?

Placement of a cuff around the proximal muscle - rush of metabolites passes through after taking it off to increase MU recruitment.

Only positive benefits come when doing low load resistance exercise


What is sarcopenia?

What type of exercise can prevent/reduce this?

Why does this accelerate in the elderly?

Loss of muscle mass with ageing (75+ accelerates)

Resistance exercise is most effective way

MU restructuring and protein deficiency


What are some other adaptations that occur (fibres)?

Reduction in Type IIx but increases in Type IIA and IIB fibres
Increased fascicle length and pennation angle


What are some of the neural adaptations that take place?

Cross-Education = train one side and other will change

Imagined contractions = reinforce neural pathways and get stronger


What is ultrasound techniques used for?

Measures thickness and muscle size (transverse)
Measures pennation and fascicle length (longitudinal)


What does an increased neural drive result from?

Increasing MU recruitment/synchronisation
Increasing firing frequency


What did Miller-Brown and Semler find on MU synchronisation?

Miller = MU synchro increased after 6 weeks of training

Semler = Synchro largest in weightlifters and smallest in pianists (random fire)


How does improved coordination affect MU's?

Reduces activation of antagonist muscles
Preferential recruitment of high-threshold MU's


Can we recruit faster MU's preferentially?

Slow => progressive activation of MU's to limit of recruitment at around 80-90% of MVC

Rapid => MU's recruited at lower forces


How does exercise selection affect MU activation?

Olympic Lifting = increased jump height
Traditional = increased coordination and stiffness


Why are neural adaptations hard to quantify?

Found in spine or supra-spinal
These reduce coactivation of antagonists
Reflux potentiation


How can you evoke a contraction and what effect does it have?

Electrical stimulation
Independent of central motor drive - measures the muscles capacity to peripheral fatigue


What is the difference between the merten hand method and the interpolated twitch technique?

Merten --> stimulate yourself to elicit a twitch - measure the time and size of it and take away the influence of the CNS

Interpolated --> voluntary muscle actions - measure same technique and discover how much from involuntary muscles