Week 2 readings summary Flashcards
how does CHD occur?
blood flow to myocardium is compromised due to narrowing of coronary arteries
modifiable risk factors for CVD
Dyslipidaemia
Hypertension
Smoking
Obesity
Hyperglycaemia/diabetes
non modifiable risk factors for CVD
Family history
Age
Gender
Ethnic background
3 protective mechanisms
lipoproteins
blood pressure
endothelial function
how do lipids protect?
HDL protect from CVD as it assists removal of cholesterol whereas chylomicron, LDL and VLDL do not
Higher levels of HDL associated with higher level of PA
Exercise is more likely to be beneficial to those with dyslipidaemia than in those with normal lipid/lipoprotein concentrations
When does BP remain low?
when there is a low salt intake, freedom from stressors, high levels of PA
when is hypertension less likely to develop?
in those who do PA
where is blood pressure lowering effect of exercise greatest?
in hypertensive individuals
when is post exercise hypotension?
a single session of aerobic exercise causing transient lowering of BP
lasts 24 hours
more typical on endurance athletes as less tension in muscle
what mechanisms explain blood pressure lowering effect of exercise?
Reduction in total peripheral resistance due to reduced sympathetic nerve activity
Increased responsiveness to vasodilators e.g. nitric oxide
Structural changes to arteries - increase cross sectional area and less resistance to blood flow
Resetting of blood pressure to lower level via baroreceptor reflex after exercise
coronary arteries and PA
Coronary arteries have greater dilating capacity in those that are physically active due to the activity of nitric oxide synthase (enzyme producing nitric oxide) and an enzyme that prevents the breakdown of NO (superoxide dismutase)
