Muscles & muscle actions

Question 1

What are the three types of muscle

Answer 1

Skeletal muscle (striated, voluntary)
Cardiac striated, involuntary
Smooth, Visceral involuntary digestion, bladder, lungs etc etc

Question 2

Describe the structure of muscle

Answer 2

Epimysium (surrounds muscle)
Perimysium (surrounds fascicles)
Fascicles
Endomysium (surrounds muscle fibre)
Myofybrils
Sarcomeres 
Actin (thin) 
Myosin (thick)

Question 3

What are the properties of slow twitch muscle fibres?

Answer 3

Type I
Slow oxidative 
AEROBIC (generate energy in presence of oxygen) can only happen inside MITOCHONDRIA 
High capillaries
High blood flow
Only way to metabolize fat

slow to contract (40-50 milliseconds)
slow to fatigue (no byproducts to slow it down, only water, heat, CO20
Low firing threshold (don’t’ need much stimulus)
Low capacity for force

Question 4

What activities use slow twitch muscle fibres

Answer 4

Walking, long distance running, light weight low reps,

Train slow twitch for endurance activities

Question 5

What are the properties of fast glycolytic muscle fibres

Answer 5

Type IIb
ANEROBIC production of ATP 
Uses Phosphocreatine/lactic acid system (PC) 
Low mitochondria 
Low capillaries
low myoglobin
More actin and myosin 
contacts quickly 5ms
High threshold (needs large stimulus)
high power
Fatigues easily
GLYCOLITIC PATHWAY 
Uses glucose/glycogen
produces lactic acid 
excess lactic acid prevents production of further ATP so activity has to stop

Question 6

What activities use fast twitch muscle fibres?

Answer 6

explosive movements 
Strength & power training 
heavy weight resistance
sprinting
throwing ball

Question 7

What are the properties of Type IIa fibres (FOG)

Answer 7

Intermediate pink
use both aerobic and anaerobic production
uses glycogen and/or oxygen
Some mitochondria/capillaries/myoglobin

Question 8

What are muscular adaptations to endurance training

Answer 8

will use mostly type I fibres
type I will hypertrophy
type IIb will atrpohy
Increase fat utilisation
Increases capillaries, myoglobin, mitochondria. 
Improves endurance

Question 9

What are muscular adaptations to anaerobic (strength) training?

Answer 9

Hypertrophy of type II
atrophy of type I
increased force