Muscular Skeletal System Flashcards
Shoulder muscles and bones
Trapezium, posterior deltoids, anterior deltoids, pectoralis, latissimus dorsi
Humerus, clavicle, scapula
Hip muscles and bones
Gluteus, hamstrings, psoas major
Pelvis, femur
Elbow muscles and bones
Bicep brachii and tricep brachii
Radius, ulna, humerus
Leg and knee muscles and bones
Quadriceps, hamstrings, gastrocnemius and soles
Femur,patella, tibia and fibula
Ankle and foot muscles and bones
Gastrocnemius, soleus, tibialis anterior
Tibia, fibula tarsals, metatarsals,phalanges
Wrist and hands bones
Radius, ulna, carpals, metacarpals, phalanges
Core/trunk muscles and bones
Rectus, abdominus, latisssimus dorsi
Vertebrae
Supination vs pronation and Eversion vs inversion
Supination- turning Palm of hand up = rotation between radius + humerus
Pronation- Palm down
Eversion- moving foot outwards
Inversion- moving foot inwards
Isometric contraction
- length of the muscle DOESNT CHANGE (shorten or lengthen) to develop tension
- amount of tension increases during contraction
- no movement produced/occur
-e.g if during a squat the person stopped moving at parallel the held position sill requires contraction by the quadricep muscle isomterically
Isotonic contractions
- generate force by changing length of muscle
- can be concentric contractions OR eccentric contractions
- Movement is result
Eccentric contraction
- Involves muscle lengthening while contracting under tension
- Muscle contracts eccentrically it acts as a brake
Concentric contractions
- Involves a muscle shortening while contracting under tension
Eccentric PHASE 1 ssc
- Pre loading + stretching of muscle
- Elastic energy is stored in muscle elastic component
- Muscle spindles are stimulated
Amortization stage: PHASE 2 ssc
- Transition time between the eccentric + resultant contraction
- Nerves synapse w motor neurons
- Motor neurons transmit signals to agonist muscle groups
Concentric stage: PHASE 3 ssc
- Stored elastic energy combines w voluntary concentric muscle contraction = force necessary for movement
- Elastic energy is released from muscle elastic components
- Motor neurons stimulate the agonist muscle group
Origin of a muscle
- Site of muscle attachment to the bone that doesn’t move during contraction
- Tendons that doesn’t move at origin of muscle
Insertion of muscle
- Site of muscle attachment to the freely moving bone of its joint
- Tendon that does move at insertion of muscle
Agonist vs antagonist
- Prime mover responsible for movement /muscle contracting/shortening muscle
-Muscle opposing the agonist for given movement/ Secondary mover/ muscle relaxing/ lengthening muscle
Fixation vs synergist
- Stabilizing the joint @ origin of muscle so agonist can achieve max contraction (immobilization)
- Stabilizing joint around which movement is occurring, helps agonist function effectively
First class lever system
-Fulcrum is triangle and is between load + effort
- Allows Large load to be moved w/ minimal effort
- Lacks speed + power
- attacking header; head is coming down on the ball (load) and fulcrum is pivot joint at atlas and axis + muscles at neck are effort.
- mechanical ADV + DISADv
Second class lever system
- load between effort + fulcrum
- enables you to move heavier loads
- small ROM + slow to move loads
- calf raises; ball of foot is fulcrum and gastrocnemius is effort + body weight is load and foot is lever
- Mechanical ADV
Third class lever system
- effort is between fulcrum and load
- provides speed/power + wide ROM
- greater force required then load to be moved
Bicep curl: fulcrum is elbow joint, effort is bicep contracting, load is weight lifted
- Mechanical Disadv
MECHANICAL ADVANTAGES of levers
1st= Overcome large load w minimal effort
2nd= Overcome large load w minimal effort + multiplies amount of force produced
3rd= Provides speed + distance/ Wide ROM and multiplies speed produced
MECHANICAL DISADVANTAGE
1st= Relatively slow movement
2nd= Small ROM
3rd= Amount of effort needed > load to be moved
Balanced forces
- When forces acting on object are EQUAL but OPPOSING IN DIRECTION —-> object in constant state of motion as it’s balanced due to NET FORCE = 0
Unbalanced forces
- When forces acting in object are unequal, object is MOVED in direction of larger force
- Unbalanced forces ——> acceleration OR deceleration
Law of inertia; Newton’s first law
- An object at rest tends to remain at rest
- An object in motion remains in motion at CONSTANT SPEED unless an outside forces acts upon it
- The inertia of an object is DIRECTLY proportional to its mass, a body w/ greater mass needs LARGER force to overcome its inertia than a a body w less mass
Law of acceleration; Newton’s second law
- An object will accelerate in the same direction as the force applied to it
-increase in velocity of moving object is proprtional to force applied + inversly proprtial to objects mass - E.g the harder a tennis player hits a ball = greater acceleration of racket
- F= M x A (N)
Law of action & reaction; Newton’s third law
- for every action there’s a opposite and equal reaction
- when 2 bodies/objects exert force on one another
- Action + reaction are equal + opposite and ALWAYS occur in pairs
- E.g powerlifter exerts muscular force on barbell/weight to lift it off chest during bench press + hold it above chest
STABILITY and 2 factors affecting
“The objects resistance to changing position”
- Area of base of support = having a wide base of support will increase stability
- Center of mass= point at which total BM is concentrated (raising center of mass reduces stability)
STABILITY and 2 factors affecting
- Position of line of gravity= a line of gravity closesr to center of mass will reduce stability
- Body mass= greater mass of body, more stable
Response to warming up p1-3
- Rate of Gas exchange increases, due to higher vol. of OXYGENATED blood to muscles = delayed onset of muscular fatigue
- Increase in enzyme activity within muscles = faster + more forceful muscular contractions
- Muscle viscosity reduced, improves elasticity + functional strength of muscle —-> reduced chance of injury + more efficient contractions
Response to warming up p4-7
- Speed of nerve transmission increases, allowing for improved contraction speed + force production
- Coordination between antagonistic pairs improved= better quality of movement
- Higher vol of synovial fluid produced, increasing ROM at joint
- Muscle temp increases during beginning of physical activity, improving lengthening ability of muscles/tendons = reducing risk of injury
3 functions of upper respiratory tract
- warms air
- filter out dust + bacteria
- moistens air so filtered
2 Analyse how the structural and functional characteristics of the different skeletal
muscle fibres contribute to success in different sports
The structural and functional characteristics of the different
fibres should then be related to the demands of the students
identified sport.
* Type 1 fibres are most suited to endurance based sports such
as marathon running, endurance cycling or other suitable
example(s) because of their ability to use oxygen and produce
force for long periods of time.
* Type IIx fibres are most suited to short duration, high intensity
activities such as 100m sprint, long jump or other suitable
examples because of their ability to exert rapid force.
* Type IIa fibres are most suited to intermittent sports such as
team games, tennis or other suitable examples because of their
ability to use oxygen without fatigue and produce force at high
rates when required.
Examine how the muscular ss repsonds to a warmup
- Muscle temp increases = imporoves lengthening/flexibility of muscles and reduce risk of muscle strain/tear
- muscle viscocity reduced
- Enzyme activity is facilitated
- Muscle metabolism increased
- Energy supply is made available due to brekadown of glycogen
- Increased temp leads to greater elasticity of fibres
- Increased elasticity of fibres causes greater speed and force of contraction
- increase speed of nerve transmission = more forceful/faster contractions
- More O2 is delivered to muscles = more GE in muscles tissue so muscles work longer before fatiguing
- Static stretching can reduce force of contraction
movemenst avail at shoulder
- Horizontal flexion at shoulder created by anterior deltoid + pecs e.g tucking arms in for a tuck
- Horizontal extension at shoulder created by post deltoid + lats e.g moving arms above head for prep of dive
- Adduction created by lats, traps and pecs e.g fronthand strike in tennis
- Abduction created by lats, traps, pecs and delts e.gbackhand serve in tennis/prep to throw discuss
- Rotation e.g tennis top spin/overhead serve
- Circumdruction e.g movement of arms in butterfly stroke
Outline stages of excitation and contraction during Muscle contraction
Excitation:
- Nerve impulse reaches NMJ/motor end plate
- Ach released synaptic cleft
- Nervous stimulation of muscel tissue triggers action potential
- Nerve to muscle is NMJ
Contraction:
- Ca2+ released + binds to troponin
- Tropomyosin moves to expose active site on actin
- ATP provides energy for myosin actin crossbrdiges to form
- Myosin heads form
- Slidint filament theory as myosin pulls on actin head
- Power stroke
- Recycled when ATP synthesized + relax = stimulation of nerve stops
explain 4 characteriscs of slow twitch MF (type 1) for endurance athletes
- High mitochondrial density allows better energy production from aerobic resp
- Slow contrcation time
- High oxidative caapcity
- Low glyoclytic capaicty
- High myoglobin content= better 02 carrying capacity
- High capillary density = better exchange of gases
- Small fiber diamater allows fats diffusion/GE due to small diffusion dist
- High Resistnt to fatigue + prologonged force production
- Low force production
fucntions of neurvous ss in muscle contractions
- nervous ss/CNS sends signals to MS
- electrical impulse travles to muscle via spinal cord
- nerve cell/motor neurone tranmist impulse
- impulse arrives at motor end plate/NMJ
- triggers release of ACH across synaptic cleft
- 1 motor neurone cannot stimulate whole muscle
- motor neurone stimulates motor units
- reactations based on reaction time/speed of contraction
- if impulse strong enough/all or nothing aw = muscle fibre is innerved/innervated/stimulated at NMJ
- an action potential is reached or not according to all or none law depends in motor units contracting
- wave summation
explain 4 features of type 11x (fast glycolytic twitch) for anerobic activities
- wide diamater + low capillary density + few myoglobin + small mitochondria
- Low oxidative capacity
- High in PC (phosphocreatine) –> High rate of contraction
- High stores of PC = mantain highr ate of prolonged contraction
- Increase fibre size = allows increased strength of contraction
- High force production= speed/power ouptut high
- high levels of actin + myosin = faster contraction of muscles
- High levels of ATP + glyocgen stores
- Low resist to fatigue
- Higehst force production
- High glycolitc capacity
- Fastest speed of contrcation
Roles muscles can perform
- Agonist/prime mover= responsible for movement e.g bicep brachii in flexion in bicep curl
- Antagonist= prevents overstretching of agonist e.g tricep brachii in flexion during bicep curl
- Fixator=stabalise bone where prime mover origantes e.g gluteus when kick ball
- Synergist= stabalise joint where prime mover acting
explain hwo training can adapt recruitment of diff MF types
- Low intensity/endurance training = recruitment of diff slow twitch MF
- High intensity training e.g sprinting recruits more type 11x MF
- As muscle gets stronger, fewer fibres required to provide force needed
- As load increases, type IIa will be recruited to help type 1, when load even greater IIa supports IIx
- High inetsnity training will increase rate of fibre recruitment/speed increases
- Muscle hypetrophy + increased ATP-PC stores + adaptive energy pathways
- Increase strenhth\ of contraction
SS+ function adaptations of warmup to NMS
- Exposes binding site on actin filamnets for myosin heads to attatch onto
- relayed to the CNS to innitate a nervous impulse to increase tension
- increased stimulation of heart muscle = increase CO
- Increased speed at which nerve impulse can be tranmitted
- influx of Ca2+ released = shape of troponon changes
- Muscles spindles stretched duruing movement
- Reduced Ph of blood during excercise
- increase in muscle temp
Type 11a fast oxidative glycolytic
- High oxidative capacity
- Fast contraction time
- Middle dist swimming e.g 400m
- Medium resist to fatigue
- High force production
- High glyoclytic capacity
- Medium capillary density
