Muscular System B5-B8

Question 1

2 types of muscle fibres

Answer 1

Slow twitch type 1
Fast twitch type 2 (2a and 2x)

Question 2

Type 2a

Answer 2

FOG fast twitch oxidative glycolytic
Fast contraction with high force medium fatigue. Medium mitochondria density, myoglobin content, capillary density, aerobic capacity. High anaerobic capacity
Eg 400m run

Question 3

Type 2x

Answer 3

FG fast twitch glycolytic
Fast contraction high force. Does fatigue. Low mitochondria density, myoglobin content, capillary density. Low aerobic capacity but high anaerobic capacity
Eg knockout in boxing

Question 4

All or none law

Answer 4

When you send a nerve impulse to the muscle fibres they all contract at once or none at all.

Question 5

Short term responses

Answer 5

Increased blood supply - increased demand for o2. Vasodilation
Increased muscle temp - warm blood delivered
Increased muscle pliability
Lactate accumulation - anaerobic
Micro tears - cause swelling in muscle tissue which can cause pressure on nerve endings and pain
DOMS - caused by microtears

Question 6

Long term adaptations

Answer 6

Hypertrophy - increase muscle strength and size
Increased tendon strength
Increase in num and size of mitochondria - M in muscle fibres. More aerobic energy
Increase in myoglobin stores - transport O2 to mitochondria
Increase in storage of glycogen - train at higher intensity. Related to energy system
Increase in efficiency of fat - use as energy
Increase tolerance to lactate

Question 7

Sarcopenia

Answer 7

lose muscles mass as we age

Question 8

Cramp

Answer 8

Painful involuntary contraction of skeletal muscles caused by fatigue

Question 9

Slow twitch muscle fibres

Answer 9

Type 1
Contract slowly low force so don’t fatigue
Aerobic. High mitochondria and myoglobin.
Hiking Everest. Marathon