1.4: The Musculoskeletal System and Analysis of Movement in Physical Activities Flashcards
What are joints?
- a joint is formed where any two or more bones meet.
- are necessary for muscles to lever bones, thus creating movement.
What are the types of joints?
- fibrous (fixed)
- cartilaginous (slightly movable)
- synovial (freely movable)
what are the two types of synovial joints?
- the ball and socket joint (shoulder and hip)
- hinge joint (elbow, knee and ankle)
Label skeleton:
- look at notes
What are ball and socket joints?
- allows movement in every direction.
- hip: ball - femur, socket - pelvis
- shoulder: ball - humerus, socket - scapula
- articulating bones:
- hip: femur and pelvis
- shoulder: humerus and scapula
Articulating definition:
- this refers to the bones that meet and move at a joint.
What movement is there at the shoulder joint?
- abduction
- adduction
- flexion
- extension
- rotation
- hyper-extension
What movement is there at the hip joint?
abduction
- adduction
- flexion
- extension
- rotation
- hyper-extension
What is a hinge joint?
- allows movement in only one direction, due to the shape of the bones making up the joint.
- examples: ankle, knee and elbow
Hinge joint - articulating bones?
- ankle: talus, tibia and fibula
- elbow: humerus, radius and ulna
- knee: femur and tibia
what are the types of planes?
- sagittal plane (transverse axis)
- frontal plane (sagittal axis)
- transverse plane (longitudinal axis)
What is the sagittal plane?
- this is a vertical plane, which divides the body into right and left halves
What is the frontal plane?
- a vertical plane that divides the body into front and back halves.
What is the transverse plane?
- this divides the body into upper and lower halves.
Différent planes - sporting examples?
- sagittal: bicep curl
- frontal: cartwheel
- transverse: ice-skating 360 degrees spin
What are the three axes of movement?
- transverse axis: runs from the side to side across the body.
- sagittal axis: runs from front to back
- longitudinal axis/ runs from top to bottom.
Movements in a sagittal plane about a transverse axis?
- flexion
- extension
- hyper-extension
- (plantar flexion and dorsiflexion)
Movements in a frontal plane about a sagittal axis?
- abduction
- adduction
Movements in a transverse about a longitudinal axis?
- horizontal abduction
- horizontal adduction
Flexion définition:
- decreasing the angle between the bones of a joint
Extension definition:
- increasing the angle between the bones of a joint
Plantar- flexion définition:
- pointing the toes towards the ground/ pulling up on your toes.
Dorsiflexion definition:
- pulling the toes up towards the shin
Hyper-extension definition:
- increasing the angle beyond 180 degrees between the bones of a joint.
Abduction définition:
- movement of a body part (limb) away from the midline of the body
Adduction définition:
- movement of a body part towards the body’s midline.
Horizontal abduction définition:
- movement of a limb forwards while it is held parallel to the ground.
Horizontal adduction définition:
- movement of a limb backwards while it is being held parallel to the ground.
Flexion and extension at the shoulder:
- flexion: raising the arms forward
- extension: lowering the arm down and backwards
Agonist definition:
- the muscle that is responsible for the movement that is occurring.
Antagonist definition:
- the muscle that works in opposition to the agonist (to help produce a co-ordinated movement)
What is the antagonistic muscle action?
- when one muscle is acting as an agonist and the other is acting the antagonist, the muscles are said to be working together as a pair to produce the required movement.
elbow flexion - agonist and antagonist
- agonist: biceps
- antagonist: triceps
elbow extension - agonist and antagonist :
- agonist: triceps
- antagonist: biceps
Ankle plantar flexion - agonist and antagonist:
- agonist: gastrocnemius
- antagonist: tibialis anterior
Ankle dorsiflexion - agonist and antagonist:
- agonist: tibialis anterior
- antagonist: gastrocnemius
Knee flexion - agonist and antagonist:
- agonist: hamstrings
- antagonist: quadriceps
Knee extension - agonist and antagonist:
- agonist: quadriceps
- antagonist: hamstrings
Hip flexion - agonist and antagonist:
- agonist: hip flexors (iliopsoas)
- antagonist: gluteals
Hip extension/hyper-extension agonist and antagonist:
- agonist: gluteals
- antagonist: hip flexors
Hip adduction - agonist and antagonist:
- agonist: adductors (adductor brevis/longus/magnus
- antagonist: tensor fascia latae and gluteus medius/minimus
Hip abduction - agonist and antagonist:
- agonist: tensor fascia latae and gluteus medius/minimus
- antagonist: adductors (adductor brevis/longus/magnus
Hip horizontal adduction - agonist and antagonist:
- agonist: adductors
- antagonist: tensor fascia latae and gluteus medius/minimus
Hip horizontal abduction - agonist and antagonist:
- agonist: tensor fascia latae and gluteus medius/minimus
- antagonist: adductors
Shoulder flexion - agonist and antagonist:
- agonist: anterior deltoid
- antagonist: latissimus dorsi
Shoulder extension/hyper-extension - agonist and antagonist:
- agonist: latissimus dorsi
- antagonist: pectorals
Shoulder horizontal abduction - agonist and antagonist:
- agonist: latissimus dorsi
- antagonist: pectorals
Shoulder horizontal adduction - agonist and antagonist:
- agonist: pectorals
- antagonist: latissimus dorsi
Shoulder adduction - agonist and antagonist:
- agonist: posterior deltoid/ latissimus dorsi
- antagonist: middle deltoid/supraspinatus
Shoulder abduction - agonist and antagonist:
- agonist: middle deltoid/ supraspinatus
- antagonist: posterior deltoid/ latissimus dorsi.
What are the two types of muscular contraction?
- isotonic contraction
- isometric contraction
What is an isotonic contraction?
- when a muscle contracts to make movement.
- two types: concentric and eccentric
What is a concentric contraction?
- when a muscle shortens under tension
- e.g. during the upward phase of an arm curl - the biceps performs a concentric contestation as it shortens to produce flexion of the elbow
What is an eccentric contraction?
- when a muscle lengthens under tension or performs negative work and acts like a brake
- e.g. landing from a standing jump - quads performing negative work as they are supporting the weight of the body when landing. The knee joint is in the flexed position but the quads are unable to relax as the weight of the body ensures that they lengthen under tension
What is an isometric contraction?
- when a muscle can context without actually lengthening or shortening and the result is that no movement occurs
- it occurs when a muscle is acting as a fixator or acting against a resistance
- e.g. crucifix position in gymnastics.
