Muscles

Question 1

What is an agonist and an antagonist muscle?

Answer 1

agonist = muscle responsible for creating movement at the joint

antagonist = opposes the agonist muscle

Question 2

What is a fixator muscle?

Answer 2

muscle that stabilises one part of the body while the other moves

Question 3

What is an isotonic muscle contraction?

Answer 3

a muscular contraction where the muscles contraction changes length

Question 4

Whats the difference between eccentric and concentric muscular contractions?

Answer 4

eccentric = where the muscle lengthens during contraction

concentric = where the muscle shortens during contraction

Question 5

What is an isometric muscular contraction?

Answer 5

where the muscle is under tension but there is no visible movement

Question 6

What is a motor unit and how does it work?

Answer 6

• consists of a motor neurone and muscle fibre
• nerve impulse is conducted down the axon of the neurone by an action potential
• the action potential travels to neuromuscular junction

Question 7

What is the all or none law?

Answer 7

if an electrical impulse is above the threshold required the fibres in motor unit contract (if below the threshold none contract)

Question 8

What are the structural features of slow oxidative muscle fibres?

Answer 8

• small motor neurone size
• few fibres per neurone
• high mitochondria density
• high myoglobin content
• high capillary density
• low PC + glycogen stores

Question 9

What are the functional features of slow oxidative muscle fibres?

Answer 9

• slow contraction speed
• low force produced
• high fatigue resistance
• high aerobic capacity
• low anaerobic capacity

Question 10

What are structural features of fast oxidative glycolitic muscle fibres?

Answer 10

• large motor neurone size
• many fibres per neurone
• medium mitochondria density
• medium myoglobin content
• medium capillary density
• high PC + glycogen stores

Question 11

What are functional features of fast oxidative glycolytic muscle fibres?

Answer 11

• fast contraction speed
• high force produced
• medium fatigue resistance
• medium aerobic capacity
• high anaerobic capacity

Question 12

What are structural features of fast oxidative muscle fibres?

Answer 12

• large motor neurone size
• many fibres per neurone
• low mitochondria density
• low myoglobin content
• low capillary density
• high PC and glycogen stores

Question 13

What are functional features of fast oxidative muscle fibres?

Answer 13

• fast contraction speed
• high force of contraction
• low fatigue resistance
• low aerobic capacity
• high anaerobic capacity

Question 14

Give a sporting example of each type of muscle fibre?

Answer 14

slow oxidative = marathon runner

Fast glycolytic = 800-1500

Fast oxidative = long jump