Circulatory System and Exercise

Heart Facts: An adult’s heart contracts on average 72 times a minute, pumping about 70 milliliters of blood with each contraction. More than one-third of the 1.2 million Americans who suffer a heart attack each year die. Leading cause of death for both men and women worldwide Sedentary lifestyle #1 risk for heart attack

Circulatory System Works with the lungs: Pulmonary System –Cardiopulmonary –Cardiorespiratory System

Purposes: Transport O 2 and nutrients to tissues Removal of CO 2 wastes from tissues Regulation of body temperature

Heart Structure

Circulation Pulmonary Circuit –To the lungs Systemic Circuit –To the body

Circulation 2 pumps in one

Pulmonary Circuit Delivers blood from the heart to the lungs Pulmonary Artery Pulmonary Vein Blood rich in CO 2 –From heart to lungs Blood rich in O 2 –From lungs to heart

Pulmonary Circulation

Gas Exchange

Systemic Circulation Aorta Vena Cava Blood rich in O 2 –From the heart to the body –Cells will die if they don’t get oxygen Blood rich in CO 2 –From body to the heart

Systemic Circulation

Both Circuits

Conductivity of the Heart

Control of the Heart Beat SinoAtrial (SA Node)- "pacemaker" –located in the right atrium –sends message to the AV Node AtrioVentricular Node –works on a 1 millisecond delay –sends message to contract the ventricle Bundle Branches Purkinje Fibers

SA Node/ AV Node

Nerve Stimulation

Injured heart tissue conducts electrical impulses more slowly than normal heart tissue. Can lead to arrhythmias –Some can be lethal

Defibrillator

EKG / ECG Electro Cardio Gram

V-fib

The Heart’s Blood Supply The heart is working muscle –Requires O 2 –Removal of waste –Delivery of nutrients Coronary Arteries deliver blood to the working heart muscle

Coronary Circulation

Coronary Arteries Branch directly from the aorta Narrow Vessels

Heart Attack Heart attack results if coronary arteries are blocked

Blocked Artery

Heart Attack Myocardial Infarction

Heart Attack Interruption of blood flow to the heart muscle Causes heart cells to die –Necrosis – cells don’t grow back –May lead to lethal arrhythmias V-fib Blood clot Tearing of plaque

Atherosclerotic Plaque

Bypass Surgery

Angioplasty

Stent

Common Cardiac Vocab Cardiac arrest – stopping of heart Cardiac arrhythmia – irregular heart beat Thrombus – blood clot –Embolus Aneurysm –Ballooning and filling of an arterial wall –Aortic aneurysm Angioplasty – balloon catheter Stent Aspirin – blood thinner Hypertension – high blood pressure

Risk Factors for Heart Attack Smoking High blood pressure Low HDL’s High LDL’s Obesity Sedentary Lifestyle

Risk Factors for Heart Attack Alcoholism –May lead to arrhythmias Diabetes Drug abuse Stress Abnormal physical exertion

Exercise and Heart Attack Exercise is cardioprotective –Heart is a stronger muscle –Increased number of blood vessels –Better cardiac output –Lower blood pressure

Exercise and Heart Attack –Reduces the incidence of heart attacks –Improves survival from heart attack –Exercise reduces the amount of myocardial damage from heart attack

Exercise Protects Against Cardiac Injury During Heart Attack

Benefits of Exercise Heart: –stronger muscle –more blood per beat –slower/ more efficient Lungs –slower/ deeper breathing –more O 2 delivery

Benefits of Exercise Arteries –less risk of atherosclerosis –lower blood pressure –lower risk of blood clots –develop new (extra) blood vessels –bigger arteries = more blood flow

Healthy Arteries

Benefits of Exercise Veins –healthy valves

Benefits of Exercise Blood –Less bad cholesterol –More good cholesterol Cells –use O 2 efficiently –get rid of more wastes –use blood sugars and insulin more efficiently

Benefits of Exercise Strengthen your heart and cardiovascular system. Improve your circulation Increase energy levels –do more activities without becoming tired or short of breath. Increase endurance.

More Benefits of Exercise Improve muscle tone and strength. Strengthen bones. Help reduce body fat / keep a healthy weight. Help reduce stress, tension, anxiety, and depression. Improve sleep.

How to Avoid Heart Attack Keep body weight low Reduce cholesterol Keep heart healthy Keep body active All can be achieved with EXERCISE