Neuromuscular System Flashcards
Name the Anterior muscles (from top to bottom)
Upper Trapezius
Deltoids
Pectoralis major
Biceps brachii
Internal obliques
Rectus abdominis
External obliques
Iliopsoas
Quadriceps
Abductors
Adductors
Tibialis anterior
Name the posterior muscles (top to bottom)
Trapezius
Rhomboids
Triceps brachii
Erector spinae
Latissimus dorsi
Gluteus maximus
Hip abductors
Hamstrings
Gastrocnemius
Soleus
What are the 3 types of muscles? Give examples.
Smooth - the digestive system
cardiac (myocardioum) - the heart
skeletal (striated) - hamstring, tricep etc
What is a smooth muscle?
- Controlled by the ANS (autonomic)
- Smooth, spindle shaped
- Involuntary - unconscious
- Found in digestive system, blood vessels and urinary and reproductive systems
- Used in processes involved in homeostasis
What is a cardiac muscle?
- Found in the heart (in chamber walls)
- Striated (striped)
- Main function is to pump blood around body
- Involuntary - unconscious
- Controlled by sinoatrial node (SAN)
What are skeletal muscles?
- Attaches to bones across joints via tendons
- Controlled by SNS (somatic)
- Striated
- Voluntary - conscious
- Contracts and pulls on the bones to produce locomotion and movement
- Resists the force of gravity to hold the body upright
Name 4 characteristics of muscle tissue
- Contractility - ability to shorten
- Extensibility - ability to stretch and lengthen
- Elasticity - Ability to return its original size and shape
- Excitability - ability to respond to stimuli from the nervous system
Name the cross sections of a muscle from outer layers to inner layers
- Tendon
- Fascia
- Muscle belly
- Epimysium
- Perimysium
- Fasciculi
- Muscle fibre
- Myofibril
What are the two types of muscle fibres?
Slow twitch (1) and fast twitch (2)
What are the characteristics of type 1 muscle fibres? (Slow)
- Red - rich in blood supply
- Aerobic activity
- Rich in mitochondria
- Lower force production
- Slow in fatigue
What are the characteristics of type 2 muscle fibres? (fast)
- White - poor blood supply
- Anaerobic activity
- Poor in mitochondria
- Higher force production
- Quick to fatigue
What are the 4 roles of muscles?
- Prime mover or agonist
- Antagonist
- Synergist
- Fixator
Explain what an agonist is
The working muscle, for example, bicep in bicep curl
Explain what an antagonist is
The opposite muscle to the agonist; allows the prime mover to work
For example triceps in a bicep curl
Explain what a synergist is
A muscle that aids or modifies agonist movement
For example the brachialis in a bicep curl
Explain what a fixator is
A muscle that stabilises the joint where movement is taking place
For example, the deltoids fix the shoulder in a bicep curl
What are the 4 types of contraction?
- Isometric
- Isotonic
- Concentric
- Eccentric
Define isometric contraction
Static
The muscle contracts but remains the same length - plank
Define isotonic contraction
Dynamic
The muscle contracts and changes length by either shortening or lengthening
Define concentric contraction
Positive
The muscle contracts and shortens - upward phase of bicep curl
Define eccentric contraction
Negative
The muscle contracts and lengthens - downward phase of a bicep curl
What are the short-term effects of exercise on muscles?
- Capillaries dilate
- Increased blood flow to working muscles
- More oxygen taken from blood by muscle
- Muscles able to contract more often and more quickly
- More muscle fibres contract in muscle
- Temperature of muscles increase - increased pliability
- Metabolism increases
What are the long-term effects of exercise on muscles?
- Individual muscle fibres get shorter and fatter, increasing thickness and strength of muscle
- Improved blood supply to muscles
- Muscle reacts more quickly to stimuli
- With correct training, fast twitch muscle fibres contract more powerfully, improving performance in maximum effort activities
- Fatigue is delayed for a few seconds
- With correct training and diet, muscle’s energy supplies become more efficient
- Metabolism increases
What are the adaptations of the body due to muscular strength training?
- Strength training usually leads to growth in muscle tissue (hypertrophy) - especially for fast twitch muscles
- Growth in response to strength training is made faster by male hormone testosterone - partly explains difference between men and female in terms of strength
- The efficiency of recruiting muscle fibres is improved - especially true in first few weeks of resistance training when rapid gains in strength can be observed
- Larger amount of fibres within the muscle can be used at any one time while strength training
What are the adaptations to the body due to muscular endurance training?
- Fuelled by lactic acid system and aerobic energy system
- Increased capillaries around muscle
- increase in size and number of mitochondria
- Improved oxygen supply to muscle and better efficiency, resulting in an offset of fatigue from lactic acid build up which improved muscular endurance
- Improved efficiency of muscle fibre recruitment - slow twitch
- Muscles look toned due to hypertrophy on slow twitch muscles
What is the central nervous system? (CNS)
- Brain and spinal cord
- Control base for the whole nervous system
- Source of all nerve impulses
What is the peripheral nervous system (PNS) ?
- Branches of nerves that transport electrical messages to and from the CNS
- Subdivides into somatic (voluntary) and autonomic (involuntary)
What is the function of a sensory neuron?
Carry messages from PNS to CNS
What is the function of a motor neuron?
Carry messages from CNS to PNS
What are the sections of a neuron?
Neuromuscular junction
Myelin sheath
Axon
Nucleus
Cell body
Dendrites
Also - action potential travels through sections mentioned
Explain what the ‘All or nothing’ law is
As long as stimulus is above threshold, action potential will always remain the same. If stimulus isn’t above threshold, there will be no potential. Action potential results in the response/contraction of a muscle.
What are the immediate effects of exercise on the neuromuscular system?
- Increased muscle temperature
- Increased muscle pliability
- Increased power output from muscles
- Increased nerve-to-muscle link
- Increased recruitment of muscle fibres
What are the long-term effects of exercise on the neuromuscular system?
- Increased muscular fitness
- Increased glycogen and CP stores in muscle
- Increase in actin and myosin
- Increased basal metabolic rate
- Improved posture
- Increased neuromuscular connections
- Increased recruitment of motor units
