Impact of Physical Activity on Cardiovascular Disease

Physical Inactivity Mortality Stat

CDC estimates 200,000 US deaths annually are due to physical inactivity alone

Sedentary Living + Low CRF Risk

Risk for all-cause mortality is over 200% higher with sedentary living and low cardiorespiratory fitness compared to those who are highly active with high CRF

Greatest Mortality Risk Reduction

Occurs when moving from low to moderate fitness levels

CHD (Coronary Heart Disease)

Facilitated by hypertension, which causes atherosclerosis and promotes arteriosclerosis over time, resulting in a progressive reduction in blood supply to the heart

Atherosclerosis

Arterial wall damage with plaque accumulation; lesions in major arteries caused by hypertension that fill with cholesterol deposits and other debris

Arteriosclerosis

Arterial wall hardening that occurs over time

LDL (Low-Density Lipoprotein)

Cholesterol that accumulates at sites of injury and can cause progressive blockage or an aneurism

HDL (High-Density Lipoprotein)

Large lipoprotein that functions in reverse transport of cholesterol; provides a protective function against CHD

Aneurism

Localized bulging of an arterial wall that can rupture

Aerobic Training Effects on CHD Risk

At 60-80% of VO2max, reduces body fat, blood pressure, and systemic inflammation; improves blood lipid profile; limits risk for myocardial ischemia, blood clots, or heart rhythm disturbances

Platelet Adhesion

The stickiness of blood; lowered through aerobic training and high-volume anaerobic endurance, reducing atherosclerosis risk

Chronic Psychological Stress (CVD link)

Promotes greater circulating cholesterol and triglycerides as well as excessive platelet adhesion via adrenal hormonal mechanisms

Myocardial Ischemia

A lack of O2 supply in the heart muscle, often due to coronary artery blockage; severe blockage can trigger a heart attack

Cardiac Fibrosis

Scarring of heart tissue that promotes blood vessel wall hardening; decreased through routine aerobic exercise

Thrombosis

A blood clot capable of causing a heart attack, stroke, or pulmonary embolism; often starts with disruption or rupture of atherosclerotic plaque

Pulmonary Embolism

Life-threatening blood clot in the pulmonary arteries of the lungs, which can cause respiratory arrest and sudden death

Deep Vein Thrombosis (DVT)

A blood clot that can occur throughout the body, but often the legs, with the potential to promote postphlebitic syndrome

Postphlebitic Syndrome

Vein inflammation and consequent symptoms such as blood flow reduction, swelling, pain, skin discoloration, and/or sores

DVT Risk Factors

Bed rest, surgery, pregnancy, varicose veins, blood-clotting disorder, obesity, smoking, family history, older age

Stroke

Sudden regional brain death due to lack of O2; primary causes include vascular blockage (ischemic) and arterial rupture (hemorrhagic)

Ischemic Stroke

Accounts for ~80% of stroke cases; primarily caused by atherosclerosis and an ensuing blood clot; common among smokers

Hemorrhagic Stroke

Primarily caused by hypertension, occurring acutely from chronic vascular damage

Smoking and CHD Risk

Smokers have a 200-400% increased risk for CHD; smoking promotes progression of atherosclerosis/arteriosclerosis

Vascular Compliance

The ability of the arteries to expand and contract to accommodate changes in blood pressure

Hypertension

The predominant underlying contributor for CVD; affects about 33% of the US population

Aerobic Training Effects on Blood Pressure

3-4 days/week for 30-60 min at 60-70% of VO2max reduces systolic BP by 4-10 mmHg and diastolic BP by 3-8 mmHg

Hypertension Risk Reduction Mechanisms

Reducing resting and submaximal exercise heart rates, reducing hormone activity that increases blood pressure, improving arterial vasodilation and vessel compliance, and creating baroreceptor adjustments

Baroreceptors

Sensory receptors involved in blood pressure regulation that adjust to help the body better manage pressure changes

Additional Hypertension Risk Factors

Genetics, race, sex, age, obesity, and diet

CVD Medications and Training

Trainers should have a baseline understanding of CVD medications, as they can impact responses to cardiovascular training (e.g., beta-blockers may reduce measured heart rates)