Chronic Adaptations to Strength Flashcards
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
