1.4 - The musculoskeletal system and analysis of movement in physical activities

Question 1

what are the three types of bones?

Answer 1

1. fibrous or fixed
2. cartilaginous or slightly moveable
3. synovial or freely moveable

Question 2

make sure you can label the bones of the body.

Answer 2

cranium to the phalanges

Question 3

what are ball and socket joints?

include examples.

Answer 3

• allows movement in every direction
• formed by round head of one bone fitting into the cup-shaped capsule of the connecting bone

example: hip and shoulder

Question 4

what are articulating bones?

include examples.

Answer 4

refers to the bones that meet and move at the joint

example: articulating bones of the hip are the femur and pelvis
the humerus and scapula articulate at the shoulder
the articulating bones at the ankle are the talus, tibia and fibula

Question 5

what are hinge joints?

include examples.

Answer 5

• this joint allows movement in only one direction (due to the shape of the bones at the joint)
  example: ankle, knee and elbow

Question 6

what is the sagittal plane?

Answer 6

vertical plane

divides the body into right and left halves

Question 7

what is the frontal plane?

Answer 7

vertical plane

divides the body into front and back halves

Question 8

what is the transverse plane?

Answer 8

divides the body into upper and lower halves

Question 9

what movement is allowed at what plane?

Answer 9

sagittal:
extension, flexion, plantar-flexion, dorsi-flexion and hyper-extension

frontal:
abduction, adduction

transverse:
rotation, horizontal abduction and horizontal adduction

Question 10

what is the transverse axis?

Answer 10

runs from side to side across the body

- with the sagittal plane

Question 11

what is the sagittal axis?

Answer 11

runs from front to back

- with the frontal plane

Question 12

what is the longitudinal axis?

Answer 12

runs from top to bottom

- with the transverse plane

Question 13

define flexion

Answer 13

decreasing the angle between the bones of a joint

Question 14

define extension

Answer 14

increasing the angle between the bones of a joint

Question 15

what is hyper-extension?

Answer 15

increasing the angle beyond 180 degrees between the bones of a joint

Question 16

what is adduction?

Answer 16

movement towards the midline of your body

Question 17

what is abduction?

Answer 17

movement away from the midline of your body

Question 18

what is horizontal abduction?

Answer 18

movement of the arm forward across the body at 90 degrees to shoulder abduction

Question 19

what is horizontal adduction?

Answer 19

movement of the arms backwards across the body to shoulder abduction

Question 20

what is an agonist?

Answer 20

the muscle that is responsible for the movement that is occuring

Question 21

what is an antagonist?

Answer 21

the muscle that works in opposition to the agonist (to help produce a coordinated movement)

Question 22

what are antagonistic muscle pairs?

Answer 22

when one muscle is acting as an agonist, contracting
and the other is acting as an antagonist, relaxing and lengthening
they work together as a pair to create the required movement

Question 23

make sure you know the main agonist and antagonist for each of the joint actions

Answer 23

pg 44

Question 24

what are isotonic contractions?

Answer 24

contractions that create movement

Question 25

what are the two types of isotonic contractions?

Answer 25

concentric and eccentric contractions

Question 26

what are concentric contractions?

Answer 26

when a muscle shortens under tension

Question 27

what are eccentric contractions?

Answer 27

when a muscle lengthens under tension - and doesn’t relax (or performs negative work and acts as a break)

Question 28

what are isometric contractions?

Answer 28

when a muscle is under tension but there is no visible movement

• there is no shortening or lengthening of the muscle
• muscle acts as a fixator/ acting against resistance

e.g: crucifix position in gymnastics