Lecture 31 Flashcards
Aerobic Conditioning
is blood volume trainable
very trainable and have big advantages
more blood volume would increase someones what
increase their VO2 max
blood volume is equal to what
plasma volume + red blood cell volume
increased plasma volume leads to increased what and therefore what
increased venous return, therefore stroke volume
what is the key benefit to increased plasma volume from training
increased stroke volume
what are the other benefits to increased plasma volume from training
increased thermoregulation
off sets increased viscosity of increased red blood cell volume
how quickly can you measure the effects of training on increased plasma volume
takes only one day to become clearly measureable
what does increased red cell volume lead to
increased O2 delivery
decreased demand for peripheral blood flow
how quickly can you measure the effects of training on increased red cell volume
takes ~3 weeks to become measurable / apparent
plasma volume and red cell volume increase to a similar extent, but what do you not get more of
you do not get more O2 per litre of blood
how to stimulate increased blood volume in training
- heat
- long duration activity ?
- dehydration ?
- contractile activity (causes fluid shifts)
- upright during recovery
who will have greater blood volume, swimmers or cyclists
cyclists, because they exercise upright where as swimmers don’t
how does vascularisation influence O2 extraction and utilisation
- arteries and aretioles
- capillarisation
what is capillarisation
number of capillaries around each muscle fibre
what are the muscle factors that influence O2 extraction and utilisation
- fibre size and type
- mitochondria
- myoglobin
what mitochondria in muscle factors that influence O2 extraction and utilisation
mitochondrial …..
- size
- number
- cellular location
- oxidative enzyme concentrations
signals from exercise drive a wide range of adaptations to muscle, what are they
increased enzymes for energy storage and breakdown
increased slow twitch myosin
increased capillarisation
increased antioxidant capacity
what are the main changes to the systemic vascular capacity due to training
- larger arteries and arterioles
- some new networks of arteries and arterioles
- more capillaries
how does training increase systemic vascular capacity
- metabolic signals locally
- shear stress in blood vessels is regulated
how is shear stress in blood vessels regulated during exercise
increased nitric oxide production, so increased vessel dilation
capillarisation due to endurance training means what
more capillaries around each muscle fibre
endurance trained people have more capillaries surrounding what that untrained people
more capillaries around each muscle fibre
how does capillarisation aid exchange
decreased diffusion distance
increased time for exchange
increased blood flow into tissue
how does capillarisation increase time for exchange
more places for blood to flow so it slows down which means there is more time for exchange
how is capillarisation related to size of the fibre
bigger fibres need more capillaries
how is capillarisation related to fibre type (mitochondrial density)
oxidative fibres need more capillaries
what is the response of size of fibre in response to aerobic training
size : endurance training causes hypertrophy of Type I fibres (~30% larger)
in response to aerobic training what does the muscle fibres switch in favour of
switch in type Type II fibres towards IIa
what happens to all fibres due to aerobic training
all fibres become more oxidative
how to recruit (and therefore adapt) the type II fibres (aerobic training)
increase force (size principle of recruitment)
endurance training does what in terms of mitochondria
increased quantity of mitochondrial protein
what happens to aerobic enzymes in response to aerobic training and what are examples of these
proportional increase quantity of aerobic enzymes
- krebbs cycle and electron transport chain = to make ATP aerobically
increased aerobic enzymes due to aerobic training means what for metabolism
increased ability for aerboic metabolism
glycogen sparing in exercise means you have a greater ability to
greater ability to :
- metabolise fat
- save CHO for bursts (glycolysis) and endurance (oxidation) later
-
the effects of glycogen sparing helps. ….. and this allows for
helps increase endurance and allows higher training volume
glycogen sparing in exercise is strongly related to and caused by :
- capillarisation
- mitochondrial volume
how is capillarisation related to glycogen sparing
increased local O2 availability
increased fatty acids delivery
how does mitochondrial volume related to glycogen sparing
increased O2 utilisation
increased fatty acid uptake
increased NADH
maintain increased ATP/ADP ratio, so glycolysis inhibited
what makes oxidative muscles red
myoglobin (as does capillarisation)
what % of muscle is myoglobin
only 0.7%
what does myoglobin do
- ready source of O2
- aid diffusion of O2 from membrane to mitochondria
what can possibly happen to myoglobin in endurance trained
possibly increase
what can be used as a marker of muscle damage
myoglobin in blood can be used as a marker of muscle damage
