Lecture 27: Skeletal muscle contraction

Question 1

Limited stores of ATP in muslce produce ______s of contraction

Answer 1

2 - 4 s

Question 2

Creatine phosphate breakdown produces enough ATP for _______ s of contraction

Answer 2

20s

Question 3

What is the function of myoglobin

Answer 3

• carries oxygen around in the blood

Question 4

What are the three types of muscle fibres?

Answer 4

RED - slow type 1
INTERMEDIATE - intermediate type IIa
WHITE - fast type 11x

Question 5

What fibre type uses the aerobic metabolism?

Answer 5

• RED -slow type

Question 6

What fibre type uses the anaerobic metabolism?

Answer 6

• White - fast type

Question 7

What is the function of the RED muscle fibre type I ?

Answer 7

• Slow force production
• Slow rate
• Slow energy consumption
• Slow fatigue = endurance

Question 8

What is the function of the WHITE muscle fibre type IIa?

Answer 8

• Fast force production
• Fast rate
• Fast energy consumption
• Rapid fatigue = explosive exercise e.g sprinting

Question 9

What is physiological fatigue?

Answer 9

ATP depletion and depletion of glucose. Build up of lactic acid

Question 10

What is psychological fatigue?

Answer 10

feedback from working muscles to the brain produces the sensation of fatigue , even though muscles are still capable of contraction

Question 11

What happens when we disuse our muscles?

Answer 11

• Loss # of contractile filaments —>cell atrophy - death

- withdrawl of motor neurone

Question 12

What effect does endurance training have on our muscles?

Answer 12

• Increases blood supply to muscle
• More # of blood vessels, mitochondria & aerobic enzymes
• improved aerobic metabolism

Question 13

What effect does strength training have on our muscles?

Answer 13

• Increase # of contractile filaments —->hypertrophy
• more power
• increased anaerobic metabolism

Question 14

Where does energy for contraction come from?

Answer 14

Aerobic & anaerobic metabolism