Muscle fibres Flashcards
Be able to identify the structure and function of a Fast Glycolytic muscle cell. Be able to identify the structure and function of a Fast Oxidative muscle cell. Be able to identify the structure and function of a Slow Oxidative muscle cell. Be able to explain the links between the fibre types and performance
What are the structural characteristics of muscle fibres?
How the cell is made/built to that enables it to do its job
What are the functional characteristics of muscle fibres?
Because of how it is made or built this is how the cells functions/does its job.
What are the structural characteristics of slow oxidative type 1?
Size: Small
No. of Mitochondria: Many
No. of Capillaries: Many
Myoglobin Concentration: High
Glycogen Stores: Low
Triglyceride Stores: High
PC Stores: Low
What are the structural characteristics of Fast Oxidative Type 2a?
Size: Intermediate
No. of Mitochondria: Many
No. of Capillaries: Many
Myoglobin Concentration: High
Glycogen Stores: High
Triglyceride Stores: Low
PC Stores: High
What are the structural characteristics of Fast Glycolytic Type 2b
Size: Large
No. of Mitochondria: Few
No. of Capillaries: Few
Myoglobin Concentration: Low
Glycogen Stores: High
Triglyceride Stores: Low
PC Stores: Highest
What are the functional characteristics of slow oxidative type 1?
Contractile Speed: Slow
Contractile Strength: Low
Fatigue Resistance: High
Aerobic Capacity: High
Anaerobic Capacity: Low
What are the functional characteristics of Fast Oxidative Type 2a?
Contractile Speed: Fast
Contractile Strength: Intermediate
Fatigue Resistance: Moderate
Aerobic Capacity: Moderate
Anaerobic Capacity: High
What are the functional characteristics of Fast Glycolytic Type 2b?
Contractile Speed: Fast
Contractile Strength: High
Fatigue Resistance: Low
Aerobic Capacity: Low
Anaerobic Capacity: High
Types of activity that use Slow Oxidative Type 1?
Endurance:
Marathon, Cycling, Triathlon
Types of activities that use Fast Oxidative Glycolytic Type 2a?
Moderate to High Intensity:
400m, 800m, periods of high work rate in invasion games
Types of activities that use Fast Glycolytic Type 2b?
High Intensity and Explosive:
Weight Lifting, Long Jump, Triple Jump, 100m
What is contractile speed?
speed at which fibres contract
What is Mitochondria?
‘powerhouse’ of cell, provides large amounts of energy using O2
what are capillaries?
provide blood to muscles, site of gas exchange (O2 and CO2)
what is Myoglobin?
O2 carrier in muscle fibre (strong attraction to O2).
What does the colour mean in myoglobin?
related to myoglobin - more myoglobin = more red in colour = more o2 present in cell.
What is an aerobic reaction?
produces energy with the presence of o2
What is an anaerobic reaction?
Produces energy without the presence of o2
What is oxidative capacity?
muscles ability to work aerobically with O2
What is glycolytic capacity?
muscles ability to work anaerobically without O2
What is fatigue resistance?
how long before the cell cannot continue at that intensity
What is contractile strength?
Force at which the cell contracts.
What are the fuel sources?
fats - require more O2
Glycogen - can use O2 or not
PC - up to 10 seconds without O2.
What is Slow Twitch (Type 1) Muscle Fibres?
- Type 1/SO (Slow oxidative) MF are recruited for sub-maximal aerobic work
- Produce LOW force
- They recover quickly and are available for recruitment in about 90 secs
- Use oxygen (aerobic) to create energy
what are Fast Twitch (Type 2) Muscle Fibres (Fast Twitch Glycolytic (IIb)/FTG (fast glycolytic))
- Use glycogen as main energy source
- Do not require oxygen (anaerobic) Fast
Twitch - High contraction speed and strength
- Explosive activities
what are Fast Twitch (Type 2) Muscle Fibres (what are Fast Twitch (Type 2) Muscle Fibres)
Share characteristics of type I and type IIb
Used in partly anaerobic exercise but has aerobic properties.
What is a Motor Unit?
made up of a motor neuron and the skeletal muscle fibers innervated by that motor unit.
what is a Motor Neuron?
a nerve cell forming part of a pathway along which impulses pass from the brain or spinal cord to a muscle
What is a Muscle Fibre?
are the cells or basic building block of the muscle.
