physiological adaptations to resistance training Flashcards
1
Q
neural adaptations with any new task….
A
- early increases in strength (newbie gains)
- coordination
- learning increases activation of prime mover muscles
2
Q
recognizing changes from RT
A
- depends on movement literacy, skills that transfer across a person
- high movement = easier
- low movement = harder
- general training age
- after a plateau, gains start to come from physiological adaptations
- cross-over effect : gains/strength travel when working on one muscle
ex. greater cross-over = higher hypertrophy
3
Q
firing frequency
A
- RT allows motor units to maintain consistent firing intervals at lower rates = maintaining forceful contractions for longer periods of time
- higher threshold MU requiring more neural input) are able to fire longer before firing intermittently or shutting off
4
Q
specifically to velocity
A
- nature to which exercise is performed
- change = training in that manor
- MAX RFD (exp > heavy resistance training (HRT))
- Peak force (HRT > EXP)
- MU activation (EPX > HRT at early peak onset)
- SAID principle
5
Q
increased synchronization
A
- synergists and antagonists
- untrained
- strong and rapid movements
- highly precise
- all these increase antagonist activation
6
Q
hormone response to RT
A
- most influential to alter hormone concentrations
- optimal programing to change these hormones
7
Q
optimal programming includes …
A
- MU recruitments
- exercise selection
- intensity, volume, rest
- nutritional intake
- need to recover in order to capitalize on stress!
8
Q
testosterone
A
- increases protein synthesis + inhibits protein breakdown rates
- RT increased total test. in males, conflicting results in females
- differences in training age, physiological ceiling, volume intensity (> 80% 1RM)
9
Q
testosterone response to RT
A
- increases hypertrophy
- free testosterone in RT vs. endurance training
- certain training factors impact differently
- sequencing of exercise
- be careful of diminishing returns !
10
Q
sequencing of exercise
A
- multijoint over single joint exercises INCREASES testosterone
- 80-85% elicits highest response
11
Q
yerkes-dodson law
A
- relationship between pressure and performance
- 4 sets, 6-8 reps, 80-85% intensity
- sweet spot at the top of the bell-curve
12
Q
testosterone response in females
A
- limited concentrations -> minimal response to RT
- possible chronic adaptations with correct programming
- low volume circuit training ( increases at 12 weeks/ decrease baseline at 24 weeks)
- periodized high volume multi set programming increases @ 12 weeks / doubly increases at 24 weeks
- may be a result of growth hormone in females
13
Q
human growth hormone
A
- stimulates uptake of amino acids to make muscles
- secreted by pituitary gland
- RT causes secretion of GH isoforms with extended half lives = sustained action on target muscle tissue including skeletal muscle
- upregulation of IGF-1
- temporary elevation of GH aprox. 30 min part RT
-> impaceted by exercise selection, intensity, volume, and rest
14
Q
cortisol
A
- “stress hormone” (stress is stress is stress)
- detrimental to muscle development b/c it reduces protein synthesis
- acute response increases with high intensity/volume, volume being the biggest driver, and rest periods decreasing the acute response
- buffered by CHO (carbs) (reduces cortisol possibly)
- when following a training program there is a less acute response to cortisol b/c the body becomes used to it
ex. crossfit = bad to buffer cortisol and recover
15
Q
Insulin-like growth factor (IGF-1)
A
- no optimal prescription
- provided main anabolic response for whole body
- deceases proteolysis (atrophy)
- hypertrophy increases the rate of protein synthesis
- RT enhances acute response, IGF-1 is released during mechanical stress as it “kick-starts” hypertrophy at a muscular cellular level
- chronic levels affected by long term RT
- resting levels = trained > untrained males
- small/no change over 4-12 weeks
16
Q
why is henneman’s size principle important for hypertrophy ?
A
- type I muscle fibers are more oxidative and have a VERY HIGH training status in most people because they are used constantly
- type II are used infrequently and have a lower training state and response to training
17
Q
primary mechanisms that effect muscle growth
A
- mechanical tension
- muscle damage
- metabolic stress
18
Q
3 keys of mechanical tension
A
- nature of the tension (active/passive)
- role of external resistance
- effects of fatigue
19
Q
nature of the tension
A
- active is preferred
- passive includes myofibrils and muscle segments
20
Q
role of external resistance
A
- extent of MU firing frequency is influenced by % external resistance
- larger resistance = slower contraction velocities = more actin-myosin cross-bridges = increase in tension that each fiber provides
- fatiguing muscle types as exercise progresses
- time / tension = giving muscle fibers time to be exposed to elicit cellular responses
21
Q
effects of fatigue
A
- increase in fatigue = decrease in contraction velocity
- working muscle fibers = unable to produce required force to do the work — higher threshold MU required
- slower speeds = more cross-bridging = more mechanical tension on individual fibers
- increase motor recruitment = greater stim of muscle fibers = increase hypertrophy response
22
Q
muscle damage
A
- can occur to various components of contractile tissue (inflammatory response )
- eccentric = increase in muscle fiber length
- concentric = increase in fiber diameter
- need to have a balance and alternation!
23
Q
metabolic stress
A
- anerobic glycolysis for ATP = build up of lactate, hydrogen ions (acid), and phosphates
- muscle ischemia
- fatiguing sets that produce metabolic stress are directly linked to mechanical tension –> more high threshold MU needed to be recruited
24
Q
muscle ischemia
A
- restriction of blood flow causing a shortage of O2 can increase metabolites
