Muscle Fibre types

Question 1

Slow Twitch fibres (5 things, 1 example)

Answer 1

• Known as slow oxidative OR Type 1
• Small amount of force produced
• Resistant to fatigue for a long period of time
• Structurally designed to store oxygen in myoglobin and process oxygen in the mitochondria
• Works aerobically
  e.g. gastrocnemius may have 70% of these muscle fibres

Question 2

Fast oxidative glycolytic (3 things, 2 examples)

Answer 2

• Structurally designed to produce a large amount of force and quickly
• Also known as FOG, and Type 2a
• Is also capable of resisting fatigue

Examples

    - High intensity activities such as an 800m runner will have a high proportion of these
    - Team sports

Question 3

Fast glycolytic (5 things, 2 examples)

Answer 3

• Designed to work anaerobically
• Also known as FG, and Type 2b
• Create largest amount of force
• Fatigue quickly
• Have large stores of phosphocreatine – rapid energy production

Examples:

 - Used in sports that are of high intensity, e.g. 100m sprint
 - Approximately 70% of his gastrocnemius would be made up of these muscles

Question 4

Muscle fibre type and exercise recovery - Slow Twitch

What type of activity is it for?
What is the force of contraction like?
What is their recovery period like?
How often can it be used and why?
What is the ratio?

Answer 4

• Recruited for sub-maximal aerobic work
• Contract intermittently to create low force of contraction
• Have a quick recovery period
• No fibre damage associated with aerobic training meaning it can be performed on a daily basis
• Work: relief ratio 1:1 OR 1: 0.5

Question 5

Muscle fibre type and exercise recovery - Fast Glycolytic

When is it used? (2 things)
How often can it be used?
What is the recovery like?
What is the ratio?
What should you do when it comes to weight training?

Answer 5

• Only recruited in the last 20-30 seconds of contraction; when the activity requires maximal effort very quickly
• Often associated with muscle fibre damage aka DOMS
• Takes much longer to recover from – if used to exhaustion it will take 4-10 days to recover
• Work: relief ratio 1:3, e.g. 3-5 mins rest between sets of 2-6 reps
• When weight training you should ideally leave 48 hours between before working the same muscle group.