Exercise Physiology Flashcards
what does exercise do homeostasis and body systems
Exercise disrupts homeostasis and often requires prolonged coordination among most body systems (such as muscular skeletal and nervous stem)
what changes with maximal exercise
With exercise heart rate , stroke volume , cardiac output, systolic pressure decreases but diastolic pressure decreases
Cardiac output during excerise
CO increases in proportion to work load
CO = HR X SV
what controls of heart rate
Control of heart rate is coordinated by cardiovascular control centre in the brain stem
why does heart rate increase
immediate response to exercise is Heart rate increases to deliver more oxygenated blood to the exercising muscle
why happens when regualr excerise
the heart long-term adaptation to a regular exercise programme increases strength and efficiency
What is stroke volume
control of stroke volume by intrinsic and extrinsic control
Intrinsic : muscular contraction compress veins and vasoconstriction
Extrinsic : sympathetic stimulation and adrenaline
how does stroke volume increase
Increase venous return increases end diastolic volume and increase in strength of cardiac contraction which increases stroke volume
what does increase sympathetic activity
increase sympathetic activity increases venous return and strength of cardiac contraction
what does the AV node do
AV node ensure that there is enough time to fill the heart with blood as it stops the action potential to help keep the pace of the heart
How ventricualr volume chnages at increase heart rate
with increased heart rate decreases the time for a heart beep. Normal heart rate has a rapid reduced fillings and increase caused by atrial contraction
change of body systems energy taking when exercising
most body systems’ energy decreases during exercise as not important except the brain which always needs a specific amount and skeletal muscle increases because of the movement
how PO2 PCO2 H+ muscle temeprature chnages in excerise
exercise causes PO2 fall , PCO2 increases, H+ increases and muscle temperature rises
what does PO2 PCO2 H+ cause
PO2 PCO2 H+ and muscle temperature lead to metabolic hyperaemia
PO2 PCO2 H+ controls override what
PO2 PCO2 H+ controls override generalised sympathetic vasoconstriction
PO2 PCO2 H+ are reinforced by what
PO2 PCO2 H+ are reinforced by the vasodilatory effects of adrenaline
metabolic hyperaemia
increase in oxygen needs , increases blood flow, which causes vasodilation of coronary vessels leading to increase adenosine which increases metabolic activity of cardiac muscle cells
blood pressure during exercise
during exercise systolic pressure greatly increases and diastolic blood pressure stays the same or decreases
calculation of TPR
resistance inversely proportional to r4
blood pressure is proportional to TPR
how does the body meet metabolic demands
to meet the metabolic demands of the skeletal muscle there is a large drop in TPR brought about by the vasodilation of the arterioles supplying the working muscles
why does DBP and SBP increase or drop
what is the overall effect
diastolic BP drops due to decreased TPR
Systolic BP is increased due to increased CO
the overall effect is a marginal increase MABP
ventilation increase during excerise
ventilation VE, VO2 , VCO2 increases during exercises
oxygen deficit
oxygen uptake during exercise is steady amount but it increases until it reaches this steady rate
oxygen deficit is the difference between oxygen uptake in the first few minutes and the point it reaches a steady state (lag phase)
what is oxygen debt
once exercise stops recovery phase occurs which is oxygen debt to combat this oxygen is consumed above the resting state. this is metabolic rate increases heart and increases ventilation
increasing rate of external work
VE increases disproportionately to VO2, while VO2 exactly matches workload until VO2 max
what happens excerise
In serve exercise lactic acid produced
H+ stimulates peripheral chemoreceptors
Ventilation excessively stimulated
ventilation
CO2 excessively blown off - VCO2 exceeds VO2
what happens to arterial PO2 and PCO2
Arterial PO2 and Aterial PCO2 do not change
what does Slight decline in arterial PCO2 during heavy exercise do
Slight decline in arterial PCO2 during heavy exercise + ventilation increases abruptly at the onset of exercise long before changes in arterial blood gases can influence the respiratory centre
factors the may increase ventilation during exercise
reflexes originating from body movement
increase in body temperature
adrenaline release
impulses from the cerebral cortex
what does excise physiologists
VO2 max measurements to prescribe or adjust training programmes to help individuals achieve their optimal level of aerobic conditioning
what happens to surface are aduring excerise
during excerise the surface area for exchange can be increase to enhance the rate of gas transfer
what does increase CO do
increase CO increases pulmonary Blood pressure which forces open capillaries
why are alveolar membranes are stretched
alveolar membranes are stretched due to larger tidal volume
Ve = TV x Rf
