Neuro-Muscular System Flashcards
AUTONOMIC NERVOUS SYSTEM AND NEUROMUSCULAR SYSTEM
The autonomic nervous system (ANS) regulates the function of our internal organs such as the heart and controls some of our skeletal muscles within the body. The movement of muscles during exercise is controlled by the brain via nerves. The neuromuscular system is where the nervous system and the muscles work together to allow movement. The sympathetic and parasympathetic systems transmit information from the brain to the parts of the body that need to adjust what they are doing to prepare for exercise. We know already that the sympathetic system prepares the body for exercise and the parasympathetic has the opposite effect, helping the body systems to slow down during recovery.
Why are some people able to run so much faster than others, while some people may run slower but can keep going for hours?
One reason is that there are three different types of muscle fibre and any one individual will have a different mix of these fibre types. As the fibres have distinct characteristics, this will affect performance in certain sporting activities. The mix of fibres in your physiological make-up is genetically determined and largely unaffected by training.
What are the 3 types of muscle fibre?
- Type 1 - Slow oxidative (SO) —- SLOW TWITCH —- - Type 2a - Fast oxidative glycolytic (FOG) - Type 2b - Fast glycolytic (FG) TYPE 2 = Fast twitch
Type 1 slow oxidative (SO) muscle fibres How do they contract compared to fast twitch?
They contract more slowly.
Type 1 slow oxidative (SO) muscle fibres Why are they more suited to aerobic work compared to fast twitch fibres? STRUCTURAL
- Mitochondria - Blood capillaries - Myoglobin - Oxidative enzymes
Type 1 slow oxidative (SO) muscle fibres Aerobic respiration is a slow process, however, which means that.. FUNCTIONAL
- Slow twitch fibres cannot generate as much force as fast twitch fibres, but… -Produce no fatiguing by-products - Can sustain low intensity exercise for prolonged periods of time.
Individuals with a high proportion of slow twitch fibres are suited to what sports?
-Distance running -Cycling -Swimming -Rowing
Type 2 fast twitch muscle fibres - Fast twitch fibres are used for what activities? -What sort of power do the contractions have?
- High intensities - Strong force of contraction
Type 2 fast twitch muscle fibres Why are fast twitch fibres used for activities at high intensities and why do they have much stronger force of contractions?
- The motor neurone that carries the impulse is larger. - There are generally more type 2 muscle fibres attached to each motor neurone - Type 2 fibres are much larger and thicker than other muscle fibres
Type 2 fast twitch muscle fibres Why are type 2 muscle fibres suited to anaerobic work?
- They have few mitochondria, capillaries, myoglobin & oxidative enzymes - Many glycolytic enzymes
Fast twitch fibre variation - What are the two types of fast twitch?
2A fast oxidative glycolytic (FOG) muscle fibres 2B fast glycolytic (FG) muscle fibres
Type 2A fast oxidative glycolytic muscle fibres -How do they contract compared to type 1 fibres and why?
They contract more quickly and so can exert more force than type 1 fibres.
Type 2A fast oxidative glycolytic muscle fibres - How can they produce energy?
Both aerobically and anaerobically
Type 2A fast oxidative glycolytic muscle fibres - What energy are they more suited to?
Anaerobic work
Type 2A fast oxidative glycolytic muscle fibres -Being more suited to anaerobic, what does this mean?
This means that there is a rapid build-up of lactic acid which causes these fibres to fatigue quite quickly. These are, however, more resistant to fatigue than type 2b fibres.
Type 2A fast oxidative glycolytic muscle fibres What example of sports are there?
-400m -200m swim
Type 2B fast glycolytic muscle fibres - When do these fibres work and for how long?
- These fibres work at very high intensity for a short period of time
Type 2B fast glycolytic muscle fibres - How do they accumulate lactic acid?
Quickly and also have high fatigability.
Type 2B fast glycolytic muscle fibres - Examples of sports?
-100m -Throw -Jump
Size of fibre - Structural or Functional - Slow twitch (Type 1) - Fast twitch (Type 2a & 2b)
- Structural - Small/thin - Big/thick
Speed of contraction - Structural or Functional - Slow twitch (Type 1) - Fast twitch (Type 2a & 2b)
-Functional -Slow -Fast
Force of contraction - Structural or Functional - Slow twitch (Type 1) - Fast twitch (Type 2a & 2b)
-Functional -Small -Large
Fatigability - Structural or Functional - Slow twitch (Type 1) - Fast twitch (Type 2a & 2b)
-Functional - Low - High
Mitochondrial density - Structural or Functional - Slow twitch (Type 1) - Fast twitch (Type 2a & 2b)
-Structural -High -Low