Topic 5 Flashcards
Major muscles on the humn body
What is the joint/main action of the Adductor group
Hip adduction
What is the joint/main action of the Biceps Brachii
Elbow & shoulder flexion
What is the joint/main action of the Triceps brachii
elbow & shoulder extension
What is the joint/main action of the pectoralis major
shoulder horiozontal flexion (in the transverse plane)
What is the joint/main action of the Deltoid
Shoulder flexion, abduction and extension
What is the joint/main action of the Latissimus dorsi
Shoulder adduction
What is the joint/main action of the Trapezius
Shoulder girdle elevation (shrugging)and depression
What is the joint/main action of the Rectus abdominis
Trunk flexion ( the traditional “6 pack abs”as in sit-ups)
What is the joint/main action of the Erector spinae
Trunk extension (keeps us upright/ erect)
What is the joint/main action of the Gluteus maximus
Hip extension
What is the joint/main action of the Rectus femoris (part of quadriceps group)
Knee extension and hip flexion
What is the joint/main action of the Biceps femoris (part of hamstrings group)
Knee flexion and hip extension
What is the joint/main action of the Gastrocnemius
Ankle plantar flexion and knee flexion
What is the joint/main action of the Tibialis anterior
Ankle dorsiflexion
describe the common place a muscles “origin” is found?
Usually at the proximal end of said muscle. it is usually the muscles tendon thats attached to either the least moveable bone OR bone(s) that are closest to the midline
what does “insertion mean”? (muscle’s OIA)
is often the distal attachment, it is usually attached to either the more moveable bone(s) OR the bones that are furthest away from the bodys midline
list the ANTERIOR major muscles
Trapezius Deltoid Pectoralis major Biceps brachii Rectus abdominis Rectus femoris Tibialis anterior Quadriceps femoris group Adductor group (groin)
List the POSTERIOR major muscles
Trapezius Deltoid Latissimus dorsi Triceps brachii Erector spinae Gluteus maximus Biceps femoris Gastrocnemius Hamstring group
What are agonist muscles?
are the prime movers of the action being carried out, they perform the movement that is being described. For example, in a bicep curl, Biceps brachii causes the movement, elbow flexion.
What are antagonist muscles?
are the opposing muscles to the movement being carried out. sometimes they do contact with some force to control the movement. In the case above of the bicep curl, the antagonist muscles are Triceps brachii.
What are synergist muscles?
These are muscles that help the agonists carry out the movement. In the example of the bicep curl, Brachialis and Brachioradialis assist the Biceps brachii to do elbow flexion.
What are stabilizer muscles?
do not contribute to the actual movement visible, but contract isometrically to stabilise the joint around where the muscle is moving to actually cause the movement.
As the Biceps brachii originates from the scapula other muscles around the scapula would be contracting to keep it from moving when it is doing its bicep curl movement causing movement at the elbow
what are the main functions of skeletal muscles?
Allow movement
Maintain posture
Stabilise joints
Produce heat
What are the five golden rules of skeletal muscle activity?
- All muscles cross at least one joint.
(The only exception to this is some of our facial expression muscles which go from skull bones directly onto the deepest layers of the skin.) - Typically, the bulk of the muscle lies proximal to the joint crossed.
- All muscles have at least two attachments: the origin and the insertion.
- During contraction, the muscle insertion moves towards the origin.
- Muscles can only pull, they never push.
