Chapter 4 - Muscles At Work Flashcards
What is another name for static muscle contraction
Isometric contraction
What are the 2 forms and types of muscle contraction?
Static and dynamic
Static muscle contraction
Nothing moves. There is internal force exerted against an external load
How much tension can be developed from static muscle contraction
High amounts because energy used from cross bridge activation is high
Give 3 examples of static muscle contraction:
Planks
Pushing against a stable wall
Pressing your hands together
Arm wrestling
Dynamic muscle contraction
Change in limb structure that the muscle is moving around. Muscle tension/force is exerted against an external load
Internal force is _____ than the external load in dynamic muscle contraction.
Greater
Auxotonic isotonic
A dynamic contraction. The tension required to move an external load varies while the mass of the load remains constant
The strength needed to perform a barbell curl depends on what 4 internal factors?
1) the athletes physique
2) the athletes leverage
3) the angle position of the limbs
4) the speed of the movement
Isokinetic
A dynamic contraction that involves a constant speed contraction against a pre-set resistance
Where does muscle strengthening occur for isokinetic muscle contraction?
At all joints
List 5 examples of isokinetic contraction:
1) CYBEX
2) KINCOM
3) LIDO
4) HydraGym
5) nautilus (controversial)
Concentric
Involves muscle shortening while tension is generated as it goes through a range of motion; usually termed flex ion
What is an example of concentric?
Moving the heel closer to the buttocks is concentric of the hamstring
Eccentric
Involves muscle lengthening while tension is generated as it goes through a range of motion; usually termed extension
Name an example of eccentric
Moving the heel away from the buttocks is eccentric of the hamstrings
If one muscle group is being used to describe concentric what needs to be used to describe eccentric?
The same muscle group
List 8 factors influencing the force and power of muscle contractions:
1) the individuals state of health
2) the individuals training status
3) joint angle
4) muscle cross sectional area
5) speed of movement
6) muscle fiber type
7) age
8) gender
Joint angle
The type of contraction and the force required to resist an external load change as the joint angle changes
What type of muscle contractions might be required for joint angle to occur?
Static dynamic concentric eccentric may all be required
Coordination between ______ and ______ muscles is required
Agonist and antagonist muscles
Maximal force is produced at a joint angle that corresponds to ______ _______ _____ interaction
Maximal cross bridge
Muscle cross sectional area
Body mass is positively correlated with strength, provided that the mass is primarily muscle tissue or lean mass
The larger the muscle cross sectional area the more _____ it can potentially generate
Force
Maximal strength
The ability to perform maximal voluntary muscular contractions in order to overcome powerful external resistances
One repition maximum (1RM)
The greatest force that can be exerted during one repition for a given contraction of muscles
What activities are examples where greater absolute strength is necessary?
Weightlifting and track and field events
Amount of force generated over time gives us _____
Power
Relative strength
The performance of athletes classified by weight or athletes who much overcome their own body mass, depends on the proportion of maximal strength to body mass
Relative strength = _____/_____
Maximal strength/ body mass
As speed of movement _______ the force a muscle can generate _______
Increases, decreases
Speed of movement compromises cross bridges dice they cannot ______ and ______ fast enough
Couple and uncouple
Muscular endurance
The ability of a muscle to exert force as then do more and more. Important in acyclic events that involve strength and endurance including gymnastics wrestling icing downhill skiing etc.
What is the number of repitions that can be performed against a high resistance dependent on?
Maximal strength
The greater an athletes maximal strength the greater the muscular ________ at a particular load
Endurance
Endurance
The number of repitions against resistance in a certain amount of time
Vigorous cardiovascular training can lead to?
An associated decrease in the diameter of fast twitch fibers
Increased endurance can be associated with?
Decrease muscle strength as a result of a corresponding decrease in muscle volume
Activities that are solely endurance will see a loss in ______
Fast twitch muscle fibers
Activities that are solely maximum will hve no _____
Speed
What does repetitive maximal strength decrease? What does it increas?
Decrease endurance, increases strength
The greater the fast twitch fiber content of a muscle….
1) the greater the force output
2) the greater the over speed of contraction
3) the greater the fatigabiliry (decreased endurance) when the muscle has been maximally activated
The greater the slow twitch fiber content of a muscle…
1) the lower the force producing capacity
2) the slower the contraction speed
3) the greater the endurance characteristics of the muscle
What does she affect
Muscle force output
What is there a loss of with age
Fast twitch fibers
Apoptosis
Programmed cell death
Sarcopenia
The medical term that describes muscle loss
What is the differences between male and females mainly due to?
The difference that exists in muscle volume
