Skeletal and muscular systems Flashcards
1.1a content
What are the common features of a synovial joint?
- Ligament - connects bone to bone + stabilises joint
- Synovial fluid - reduces friction + nourishes articulating cartilage
- Articular cartilage - absorbs sock + allows friction free movement
- Joint capsule - encloses + strengthens joint secreting synovial fluid
- Bursa - reduces friction between tendons and bones
What are the 3 planes of movement?
- Sagittal - divides body into left and right
- Frontal - divides body into front and back (anterior/posterior)
- Transverse - divides body into upper and lower
State and describe the 3 main joint that can be found within the body. Use practical examples in your answer
- Ball and socket joint - shoulder and hip. Flexion and extension. Abduction and abduction. Horizontal flexion and extension + medial + lateral rotation
- Hinge joint - elbow, knee and ankle. Flexion, extension, Doris flexion and plantar flexion
- Condyloid joint - wrist. Flexion, extension and addiction, abduction
Define the components of movement (regarding muscles)
- Agonist - a muscle responsible for creating movement at a joint, the prime mover
- Antagonist - a muscle the opposes the agonist, providing a resistance for co-ordinated movement.
- Fixator - a muscle that stabilises one part of the body while mother part moves
State and explain the different types of muscular contractions (include sporting examples)
- Isometric - muscles contract but don’t change in length. Eg - holding a plank position
- Isotonic - concentric -muscle shortens to produce tension
State the 5 stages of the flow diagram summarising the role of a motor unit
- Nerve impulse initiated in the motor neurone cell body
- Nerve impulse conduced down the axon of the motor neurone by a nerve action potential to the synaptic cleft
- Neurotransmitter called ACh is secreted into the synaptic cleft to conduct the nerve impulse across the gap
- If the electrical charge is above the threshold the muscle fibres will contract
- This happens in an ‘all-or-none law’ fashion (depending whether stimulus is above threshold, all ,muscle fibres will give either a complete contraction or no contraction at all)
Slow oxidative muscle fibres (SO)
Key points -
-recruited and provide energy for sub-maximal aerobic work
-contract intermittently to give overall low force of contraction
-individual fibres will recover very quickly
Application for training and recovery -
-1:1 or 1:0.5 work:relief ratio
-training can be performed on a daily basis as fibre damage not associated with low intensity training
- low intensity use of SO fibres in between heavy weight training to increase blood flow to muscles + recovery
Fast oxidative glycolytic (FOG) fibres
Key points -
-designed to produce a large amount of force quickly
-have the capacity to resist fatigue
Application for training and recovery -
-used in high intensity activities lasting a few minutes
-examples = 800m running
Fast glycolytic (FG) fibres
Key points -
- recruited in the last 2-10 seconds of contraction when maximal efforts are needed quickly
- accompanied by eccentric muscle fibre damage which causes DOMS felt 24-48 hours post exercise
Application to training and recovery -
- if used to exhaustion they take 4-10 days to recover
- maximal weight training should leave 48 hours before using same muscle group
Give a sporting example for each muscle fibre
Slow oxidative - marathon running
Fast oxidative glycolytic - 800m running race
Fast Glycolytic - 100m sprint or javelin
Structural and functional characteristics of so muscle fibres
Structural -
- capillary density = high
- Mitochondria density = high
- phosphocreatine store = low
Functional -
- speed of contraction = low
- force of contraction = low
- fatigue resistance = high
- aerobic capacity = high
- anaerobic capacity = low
Structural and functional characteristics of FOG fibres
Structural -
- capillary density = high
-mitochondria density = moderate
Phosphocreatine store = high
Functional -
- contraction speed = fast
- force of contraction = high
- fatigue resistance = moderate
- aerobic capacity = moderate
- anaerobic capacity = moderate
Structural and functional characteristics of FG muscle fibres
Structural -
- capillary density = low
- mitochondria density = low
- phosphocreatine store = high
Functional characteristics -
- contraction speed = fast
- force of contraction = high
- fatigue resistance = low
- aerobic capacity = low
- anaerobic capacity = high
