Week 05 Flashcards
Power =
force x velocity
Power can be measured by…(3)?
- velocity of bar movement
- Rate of force development (isometric, isokinetic, testing modes)
- Explosive performances (speed, acceleration, vertical jump height)
Why do we care about power?
The rate at which can develop force is probably the most important factor in terms of athletic performance
- it is also related to injury mechanisms, determine starters and experienced
____ _____ muscle fibres may be a determinant for power produced
fast twicth
Neural components affecting power (4)?
- Neural drive (V wave mostly)
- Motor unit recruitment
- Rate coding / discharge rate ; how quickly we send signals to muscle
- Motor unit synchronisation (less evidence)
Do women and men have the same amount of muscle fibres?
Yes, mens fibres are just larger
Men have higher proportion of muscle area from the _____ isoform, women higher area from ____
Men type II, women type I
What are two important aspects of having high power?
- Supraspinal output (V wave)
- Ability to rapidly recruit type II motor units (and maintain a high firing rate)
What power % is most effective for increasing unloaded contraction velocity?
0% Fmax
What power % is most effective for increasing muscles strength?
100% Fmax
What power % is most effective for increasing peak muscular power in isolated muscle actions?
30% Fmax
In RT population, if we do a strength training protocol will we see an increase in strength AND power?
No, only strength
If we do strength training AS WELL AS power based training, will we see an increase in strength AND power (in novices)
Yes
It is expected that responses in elite athletes will be of _____ magnitude than of beginners
Lower
High ____ training can increase hypertrophy in novices
velocity (not load)
Power could be measured by(3):
- velocity of bar movement
- Rate of force development
- Explosive performance (speed, acceleration, etc)
Maximal force output of a muscle typically takes …..
> 300ms to develop
What is likely the most important factor in terms of athletic performance …?
The rate in which we can develop force
An ___ of _____ twitch muscle fibres increases power
increase, fast twitch
What is strongly related to the ability to produce force
muscle fibre types
RFD =
change in force / change in time
Neural involvement of power is mostly driven by the H or V wave ?
V-wave
What is the main factor in neural involvement of power?
Motor unit recruitment (how quickly we can recruit motor units)
What does the rate of coding / discharge rate mean…?
How quickly we can send signals to the muscles
What is the difference between men and womens muscle fibre types?
Men the same number, but larger fibres types than women
Two factors that will likely increase power?
- Supraspinal output
2. Ability to rapidly recruit type II (maintain high firing rate)
Up to 75ms RFD -> predominantly from…?
neural involvement
Longer than 75ms RFD -> predominantly from ….?
intrinsic muscle properties (and still neural involvement)
0% Fmax is most effective for…
increasing unloaded contraction velocity
100% Fmax is most effective for….
muscle strength gain
30% Fmax is most effective for…
increase peak muscular power in isolated muscle contractions
Why should beginners train for strength first before power?
Strength training will also increase power, but power training will not increase strength
In 24 week RT program, the first 12 weeks had the most….?
Hypertrophic and changes in force-time characteristcs
The _____ of training in the 12-24 weeks influenced the adaptation in early force development characteristics
specificity
There was an increase in ?????? up to 16 weeks
explosive power
However, in trained individuals, RT itself is may not be specific enough to improve _____
Power
In novices, changes in neural adaptations seem strong enough to overcome possible detriments from…
type IIx fibres types conversions into type IIa
Power in (0-50ms) in isolated joint movements is best explained by (3):
- contractile properties of the muscle
- early neural drive
- more so by total strength as duration of contraction increases
