KNES465-0101 Lecture 4: Arterial Function Flashcards
Endothelium
inner lining of all vessels; single cell layer.
(tunica intima)
Elastin
rubber-like material; accounts for most of the stretch of vessels at normal pressures (can be stretched over 100%)
(tunica media)
Collagen
connective tissue that is far less distensible than elastin; (can only be stretched 3-4%)
(tunica adventitia)
Smooth Muscle
regulates blood flow; contraction of vascular smooth muscle cells (VSMC) causes vasoconstriction which decreases blood flow; relaxation of VSMC causes vasodilation which increases blood flow.
(tunica media)
Sarcopenia
progressive decline in muscle mass due to aging
Arterial/vascular stiffness
refers to the material property of the arterial wall
This in turn affects the manner in which pressure, flow and diameter change.
Arterial/vascular function
refers to the balance between the vasodilating and constricting substances.
Benefits of Resistance Training
Increase Strength
(Functional Status)
Increase Bone Mineral Density (Osteoporosis)
Improve Body Composition
(Sarcopenia)
Improve Blood Glucose (Control Diabetes)
Lower Blood Pressure
(Hypertension)
Preserve/Improve Resting Metabolic Rate (Obesity)
Resistance exercise has benefits but the evidence on arterial stiffness is debatable.
Relationship Between Exercise and Arterial Stiffness
Arterial compliance (endothelial function) increases with moderate intensity exercise
Relationship Between Resistance Exercise and Arterial Stiffness
Resistance exercise tends to increase arterial stiffness, which is driven by blood pressure (can get up to 300ml/mm hg systolic).
Stiffness is necessary to accommodate the increase in pressure. Too much compliance and the artery will rupture.
Compliance
distensibility; the ability of arteries and veins to tolerate changes in volume; indicates the presence of elastic fibers and smooth muscles
