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... 8. Gender-female lower chance up until menopause-then the risk equals that of men. (*estrogen) 9. Stress-type A-high correlation with increased risk. Type B-much lower correlation. Big 3 risk factors = cigarette smoking, high BP, high cholesterol levels. Uncontrollable factors = Genetics, Gender, age Q=SVxHR Cardiac output=Stroke volume x Heart rate. -> Cardiac output = refers to the volume of blood that is pumped out of the left ventricle in 1 minute. At rest = Q=5-6 L/min. During max. exercise = Q=30 L/min. ->Stroke volume is the amount of blood that is ejected from the left ventricle in a single beat. SV-generally (average) 71 ml. ->Heart Rate= is the number of times the heart contracts in a minute. SV and Q are influenced by the amount of blood that returns to the heart (venous return). Venous return increases as a result of: 1. Venoconstriction. 2. the skeletal muscle pump. 3. The thoracic pump. 4. Nervous stimulation of the heart. Cardio-vascular fitness benefits: Greater heart mass and size. 2 increase stroke volume. 3. increased blood volume and RBC (hemoglobin) 4. increased capillary density and hypertrophy in heart muscle and 5. decreased heart rate. Heart size 1.endurance athletes have an increase in their ventricular cavity and thickness of ventricle wall therefore they have more blood per ventricle filling (SV) and a more forceful contraction than a non-athlete. 2. SV increases ->same cardiac output. **non athlete has a higher HR in order to have the same Q. 3. Blood volume and RBC increases. ->contributes to a greater venous return and heat regulation. Larger volume, more able to dissipate deep body heat. 4. Capillary density and hypertrophy in heart increase. ->greater number of capillaries surrounding. ->hypertrophy of coronary arteries. 5. Heart rate decreases in athletes. Due 2 1. cardiac hypertrophy. 2. increased sympathetic drive. and 3. decreased intrinsic pacemaker. OBESITY 1. Heredity -1 obese parent-40%chance, 2 obese parents -80% chance. 2. Glands –Thyroid gland –produces “thyroxin”, controls Basal Metabolic Rate. Hyper active ->underactivity. Cretinism. Hyperthyroidsism ->over activity.-grave`s disease. Hypothalamus –controls center for hunger and satiety. Satiation center takes 20 minutes. 3. BAT (Brown Adipose Tissue) –Can help with thermogenesis-creating heat. Plays a major role in burning off excess energy. Has a high density of “Mitochondria”. White fat tissue stores energy. Obesity and fat tissue: Obesity refers to excess or above average body fat. Obese people have larger numbers of fat cells and more lipid content in their fat cel...