Musculoskeletal system and analysis of movement in physical activity Flashcards
What is a joint?
Where two or more bones meet.
What is a ball and socket joint?
It is formed by the round head of one bone fitting into the cup-shaped capsule of the connecting bone.
It allows movement in every direction.
What are the articulating bones at the shoulder joint?
The humerus and scapula.
What are the articulating bones at the hip?
The pelvis and femur.
What are the articulting bones at the ankle?
The talus, tibia, and fibula.
What are the articulating bones at the knee?
The femur and tibia.
What are the articulating bones at the elbow?
The humerus, ulna, and radius.
What is the sagittal plane?
It divides the body into left and right ‘Sides’.
What is the frontal plane?
It divides the body into front and back halves.
What is the transverse plane?
It divides the body into upper and lower halves / top and bottom.
What are the movements possible in the sagittal plane about a transverse axis?
Flexion and extension.
Plantarflexion and dorsiflexion.
Hyper-extension
What are the movement possible in the frontal plane about a sagittal axis?
Abduction and adduction.
What are the movements possible in the transverse plane about a longitudinal axis?
Rotation
Horizontal abduction and adduction.
What is the transverse axis?
It runs from side to side across the body.
What is the sagittal axis?
It runs from front to back.
What is the longitudinal axis?
It runs from top to bottom.
Which planes pair with which axis?
Sagittal plane - transverse axis.
Frontal plane - sagittal axis.
Transverse plane - longitudinal axis.
How are joints classified?
By how much movement they allow.
What are the three types of joints?
Fibrous - fixed.
Cartilaginous - slightly moveable
Synovial - freely moveable
What is flexion?
Decreasing the angle between the bones of a joint.
What is extension?
Increasing the angle between the bones of a joint.
What is hyperextension?
Increasing the angle beyond 180° between the bones of a joint.
What is plantar-flexion?
Pointing the toes / pushing up on your toes.
What is dorsi-flexion?
Pulling the toes up towards the shin.
What is shoulder flexion and extension?
With the arms by the side of the body, raising the arms forwards is flexion and lowering the arm down and backwards is extension.
What is abduction?
Movement away from the midline of the body.
What is adduction?
Movement towards the midline of the body.
What is horizontal abduction?
The movement of the arm backwards across the body to shoulder abduction.
What is horizontal adduction?
Movement of the arm forward across the body at 90° to shoulder abduction.
What are sporting examples of movement in the frontal plane about the sagittal axis?
Star jump
Cartwheel
Diving (sideways)
Goalkeeper (sideways)
What are sporting examples of movement in the sagittal plane about the transverse axis?
Sit ups
Kicking a football
Somersaults
Bowling
Diving (forwards/backwards)
Sprinting
What are sporting examples of movement in the transverse plane about the longitudinal axis?
Pirouette
Discus throw (at the shoulder)
Pivot in netball
Tennis forehand
What is an agonist?
The muscle causing the movement that is occurring (contracting).
What is an antagonist?
The muscle that works in opposition to the agonist.
It controls and co-ordinates the movemnt. (Relaxes).
What are the agonists and antagonists of elbow flexion and extension?
Flexion: A - biceps
An - triceps
Extension: A - triceps
An - biceps
What are the agonists and antagonists of plantar-flexion and dorsi-flexion of the ankle?
Plantar: A - gastrocnemius
An - tibialis anterior
Dorsi: A - tibialis anterior
An - gastrocnemius
What are the agonists and antagonists of knee flexion and extension?
Flexion: A - hamstrings
An - quadriceps
Extension: A - quadriceps
An - hamstring
What are the agonists and antagonists of hip flexion?
A - iliopsoas/hip flexors
An - gluteals
What are the agonists and antagonists of hip extension/ hyper-extension?
A - gluteals
An - hip flexors
What are the agonists and antagonists of hip abduction and adduction?
Adduction: A - adductors (adductor brevis/longus/magnus)
An - Tensor fascia latae and gluteus medius / minimus.
Other way round for abduction.
What are the agonists and antagonists of hip horizontal adduction and abduction?
Adduction: A - adductors
An - Tenso fasica latae and gluteus medius/minimus.
Other way round for abduction.
What are the agonists and antagonists of shoulder flexion and (hyper) extension?
Flexion: A - anterior deltoid
An - latissimus dorsi
Extension: A - latissimus dorsi
An - anterior deltoid
What are the agonists and antagonists of shoulder horizontal abduction and adduction?
Abduction: A - latissimus dorsi
An - pectorals
Adduction: A - pectorals
An - latissimus dorsi
What are the agonists and antagonists of shoulder adduction and abduction?
Adduction: A - posterior deltoid / latissimus dorsi
An - middle deltoid / supraspinatus
What is an isotonic muscle contraction?
When a muscle contracts to create movement.
Two types: concentric and eccentric.
What is a concentric contraction?
When the muscle shortens as the fibres contract.
What is an eccentric contraction?
When a muscle lengthens when the fibres contract.
It can act as a brake
What is an isometric contraction?
When the muscle fibres are contracting but there is no visible movement occurring.
What are examples of concentric contractions?
During the upwards phase of an arm curl, the biceps concentrically contract.
They shorten as they contract to produce flexion of the elbow.
What are examples of eccentric contractions?
Landing from a standing jump. The quadrcieps are supporting the body weight during landing.
The knee joint is flexed but the quadriceps cannot relax as the weight of the body ensures they lengthen under tension.
What is an example of an isometric contraction?
The crucifix position in gymnastics.
The muscle is acting as a fixator or acting against resistance.
