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
