L22 Flashcards
When you train for aerobic fitness, adaptations include:
Heart Vascular system (blood vessels) Muscles Lungs increase in VO2max increase in CO increase in O2 extracted by the muscles
main change is increase in SV
Hypertrophy (increase in size) left ventricle leads to
– Increase in stroke volume
– Increase in cardiac output
– Increase in contractility- more force/beat (increased SNS)
describe physiological hypertrophy of the heart
All the continue work and pressure that the heart undergoes while under the endurance conditions leads to a physiological hypertrophy of the heart, similar to what you see this in the skeletal mussle
The hypertrophy that you see is the growth within the left ventricle. With a larger chamber of the left ventical you can get a larger SV
Not only goes the chamber size increase so does the thickness of the muscle chamber
Physiological hypertrophy = everything gets bigger but everything is still functional
describe the difference in what you would see with physiological hypertrophy compered to pathological hypertrophy (Mild hypertrophic
cardiomyopathy)
it both causes the thickness of the left ventricular wall is the same however when the wall contracts which physiological hypertrophy the ventical will still have a round shape and will still have some space within the ventical
in Mild hypertrophic
cardiomyopathy there is a non round shape (it is non uniform squeezing of the ventricle) which leads to not enough blood getting pushes out of the ventricle
SV increases with endurance training
how much can it increase by
untrained = 50-70mL/beat at rest and 80-110 during excersize
tained = 70-90 at rest and 110-150 during excersize
highly trained = 90-110 at rest and 150-220+ during exercise
what becomes a measure of fitness as adaption occures
HR
why does HR become a measure of fitness as adaption occures
HR is a really inefficient way to get O2 blood to skeletal muscles as when the HR gets too high the ventricles don’t fill
A better was of increasing the CO is to make the left vertical larger
With training athletes are able to decrease HR to do the same power
The training also lets them go longer before their HR maxes out
therefore lower HR while doing intense exercise is a measure of fitness
how does resting HR change with endurance training
decreases 1 beat per min per week of training
this is because of an increases with parasympathetic signaling to the heart
how does submaximal HR change with endurance training
when it is most obvious
HR decreases for the same intensity of exercise
this becomes more obvious at higher submaximal intensities
how does MAXIMAL HR change with endurance training
there is no significant change with training but it dose decrease with age
how does exercise cause adaptations to the vascular system
Increased blood volume, including plasma levels. • antidiuretic hormone, aldosterone- acts on kidneys to reabsorb water
Increased red blood cells
and haemoglobin
- EPO
The maximal aerobic capacity of muscle increases dramatically
because of adaptations to
exercise training
why is this
increases dramatically
because of these
adaptations which influences the relative smaller changes in
VO2max
(fiber tye, capillary supply and myoglobin)
describe fiber type in terms of muscle adaption to exercise training
Increased size and number of type I fibres (type IIa
converts to type I)
Type IIx may perform more like type IIa
Increased mitochondria and oxidative enzymes
describe cappilary supply in terms of muscle adaption to exercise training
Increased number of capillaries
May be key factor in increased VO2max
describe myoglobin in terms of muscle adaption to exercise training
Increased myoglobin content by 75 to 80%
Supports increased oxidative capacity in muscle (better extraction of O2 from the blood)
