neuromuscular fundamentals Flashcards
what is an agonist
prime movers
movements can have ? agonists
multiple
agonists may produce what contraction ?
concentric or eccentric
agonists muscle during bicep curls is
biceps brachii
what is located on opposite side of joint from agonist
Antagonists muscle
contralateral muscles are
antagonist muscles
main function of antagonist muscles is
to relax and allow agonists muscle to produce movement
surround joint or body part
stabilizers
stabilizers contract to fixate or
stabilize the area to enable body segment to produce movement
synergist assist
agonist muscles
synergists main function is to
assist in refined movement
Neutralizers
Counteract or neutralize action of another muscle to prevent undesirable movements
Force Couples
occur when two or more forces are pulling in different directions on an object, causing the object to rotate about its axis
Uniarticular Muscles
cross and act directly only on the joint that they cross Ex: Brachialis can only pull the humerus and ulna closer together
Biarticular Muscles
Muscles cross and act on two different joints Ex: Quadriceps muscle
What are the two advantages that biarticular muscles have over uniarticular muscles
- Cause and / or control motion at more than one joint
- Maintain a relatively constant length due to “shortening” at one joint and “lengthening” at another joint
Hip and Knee biarticular muscles during squats
Quadriceps : hip flexion and knee extension
Hamstrings: hip extension and knee flexion
In squatting down, hip and knee joints flex simultaneously
Quadriceps : Shorten at hip joint and lengthens at the knee joint
Hamstrings: lengthen at hip joint and shorten at knee joint
Multiarticular Muscles
act on three or more joints between their origin and insertion crossing multiple joints
Active Insufficiency
is reached when the muscle becomes shortened to the point that it can not generate or maintain active tension
Passively Insufficiency
is reached when the opposing muscle becomes stretched to the point where it can no longer lengthen and allow movement
When concentrically contracting quadriceps to simultaneously cause hip flexion and knee extension, no further hip flexion and knee extension is achieved beyond a certain range of motion. This occurs because of the
Active insufficiency of the quadriceps
When trying to perform hip extension with knee in fully flexed position, it is difficult to extend hip beyond a certain point because of
Passive insufficiency of hip flexors (quadriceps)
