Other Exam 1 Info Flashcards
All or none principle
fibers either contract completely or not at all
Force-velocity principle
faster movement means less force can be moved
length-tension principle
optimally contraction occurs when the fibers are stretched just a little
muscle fiber cross-section principle
larger cross section= stronger contraction (hypertrophy)
how does size and motor unit recruitment contraction
muscle with more motor unit innervation have a stronger contraction
how does connective tissue strength influence muscle contraction?
the stronger tendons surrounding a muscle are, the more force the muscle can generate
nervous inhibition threshold principle
with training, the body will be able to accept higher forces before inhibiting contraction
describe PNF stretching
put muscle in a stretched position. then contract the stretched muscle against some form of resistance. this will trigger the GTO which will result in relaxation of the muscle
Main reason for delayed muscle soreness
damage to connective tissue
what is static stretching
just holding joint in a position opp of what the muscle does to contract
what is ballistic stretching
more elastic and less permanent. short term stretching that involves movement
problem with ballistic stretching
stretch reflex can be triggered which tells the muscle to come back and shorten because it has been stretched too far
acute vs. delayed muscle sorenesss
acute happens during the activity and delayed happens 24-48 hours after.
what are things that are associated w/ delayed muscle soreness (4 things)
- ) too much eccentric work
- ) progressing too quickly
- ) damage to conn tissue
- ) poor form (bc small synergists are being used)
* * stretching at the end can help alleviate DMS
what is the Q effect
every 10 degrees Celsius incr= a doubling of metabolic rate
What is VT1
when blood lactate starts to accumulate. starting to breath a little heavier. Anaerobic threshold corresponds to this
What is VT2
when high accumulation of lactic acid is happening and body is not able to clear it adequately. hyperventilation happens here and this corresponds to lactate threshold
point at which there is no longer a proportionate incr in HR in response to increasing intensity
HTRP (heart rate return point)
1 MET=
the amount of oxygen consumed while resting
what is the Valsalva maneuver
when venous return to the heart drops due to straining and not breathing. causes stroke volume to decr and heart rate would have to compensate
what does a GTO do?
says there is too much contraction occurring causes a relaxation in the muscle when there is too much contraction
what does a muscle spindle do
responds to too much stretch by contracting the muscle
what is reciprocal innervation
one on muscle is contracting, its opposing muscle has to be relaxing. this allows for coordinated movement
what is wolf’s law
tissues change due to the stresses placed on them
describe how to incr flexibility permanently
- hold for long duration w/adequate load
- let the tissue cool in the lengthened state
describe the difference between active and passive rom
active rom involves contraction of opposing muscle group and passive rom is when the muscle is not really doing any of the work
DMS is most associated with what type of work
eccentric due to friction forces
main reason for DMS?
damage to connective tissue
what is the load-deformation curve?
the amount of deformation that occurs when a stretch load is applied.
what is the elastic limit
the region of stretch beyond where the tissue can return to its normal length once the applied force is removed
what are the purposes for the acute physiological changes that occur when going from a nonmoving to moving position?
- ) Provide oxygen to working cells
- ) remove metabolic waste products
- ) dissipate heat from atp production
