KIN 362 1st Edition Exam 3 Study Guide Exercise Physiology CARDIOVASCULAR UNIT Morphology of Heart know shape and structure of heart Athletes Heart Not realted to athletes or to training Abnormal hypertrophy of the heart particularly the left ventricle The pathological cause is chronic overload on the heart Training Response Endurance training hypertrophy larger volume Due to larger end diastolic volume from chronic volume overload Strong heart Anaerobic Training increased thickness of ventricular walls smaller volume Adaptations to high pressures stronger heart Coronary Circulation training effects are increases in collateral circulation Additional vessels opened and formed about the heart Circulation also works as protection against large myocardial infarction Form anastomoses connections between blood vessels in diseased state Low intensity aerobic programs will increase collateral circulation Muscle Pump Venous Return muscle pump contracting and relaxing of skeletal muscles to help push blood back to the heart It is primarily muscles such as gastrocnemius in legs that aid in venous return against gravity This is the reason to warm down following exercise Venous Return valves within the veins allow blood to flow in ony one direction toward the heart The smallest muscular contractions or minor pressure changes within the thoracic cavity with breathing readily compress the veins The alternate compression and relaxation of veins and the one way action of their valves provide a milking action that propels blood back to the heart Without valves blood would stagnate in veins of the extremities and people would faint everytime they stood up because of reduced venous return and cerebral blood flow Warm up Cool down These notes represent a detailed interpretation of the professor s lecture GradeBuddy is best used as a supplement to your own notes not as a substitute warm up increases temperature of soft tissue Redistributes blood from inactive to active areas Increases heart rate from a resting rate to a higher rate that approximates exercise HR Dynamically stretch muscles Increases speed of nerve impulses Cool down Warm down following strenuous exercise to increase to use fo the muscle pup so as to distribute blood back to organs from which it came and maintain increased circulation to carry metabolic wastes away from cell Blood and blood volume Heart Rate Beats per minute Easily affected by emotion temperature food ingestion position genetics and health status Heart rate is regulated by the autonomic nervous system The sympathetic increases HR and Parasympathetic decreases HR Parasympathetic also controls resting heart rate Stroke Volume Cardiovascular Drif Stroke Volume volume of blood ejected from the heart beat A larger stroke volume is an indication of a strong heart Stroke volume has the most significant change with training Cardiovascular Drift after about 15 minutes at steady state exercise HR increases and SV decreases It describes the gradual time dependent downward drift in several cardiovascular responses most notably stroke volume with concomitant heart rate increase during prolonged steady rate exercise Under these circumstances a person must exercise at lower intensity than if cardiovascular drift did not occur Submaximal exercise for 15 munutes decreases plasma volume which decreases stroke volume A reduced stoke volume initiates a compensatory heart rate increases to maintain a nearly constant cardiac output Cardiac Output Bed Rest Study Cardiac output HR x SV It is the volume of blood ejected per minute This best measures cardiovascular function It is also highly related to VO2 Bed Rest Study 5 men 3 trained 2 average fitness 20 days of bed rest Average loss in function VO2 was 27 This demonstrates the relationship between CO and VO2 Blood Pressure systolic pressure greatest pressure during contraction Normal range of rest 100140 mmHg Diastolic pressure lowest pressure during filling stage Normal range is 70 90 mmHg Normotensive Upper Body Exercise Redistribution of Blood Sudden Cardiac Death Training Changes systolic pressure is lowered at rest and at submaximal exercise Diastolic pressure is lowered at rest and at submaximal exercise In a hypertensive person the pressures are lowered more in response to training Exercise Insomnia Prolonged strenuous exercise causes an increase in circulating catecholamines from the sympathetic nercous system Excitatory effects of these may last many hours Exercise Prescription Threshold Heart Rate the maximum heart threshold is the maximum effort you re able to maintain while your body can still remove the lactate acid being used by the muscles Rating of Perceived Exertion a way of measuring physical activity intensity level Perceived exertion is how hard you feel your body is working Electrocardiograms a record of display of a person s heartbeat produced by electrocardiography Normal Sinus Rhythm the characteristic rhythm of the healthy human heart MSR is the rhythm that originates from the sinus node The Rate in MSR is generally regular but will vary depending on autonomic inputs into the sinus node Premature Beats indicates that coronary blood supply is poor ischemia or that there isi poor oxygenation The conduction of the depolarization could be slower It might not follow normal pathways Carotid Pulse can normally be felt in the neck by pressing the fingertips against the side of the windpipe or trachea Warmup Implications to ECG Exercise Physiology Respiratory Topics Capacity of respiratory system Maximal capacity 1g of Hb can bind 1 34mL of oxygen 100 saturation METS expressing oxygen cost of activity 1 MET 3 5 mll kg min Surface area changes with training Hypoxia deficiency in the amount of oxygen reaching the tissues Stitch in the side muscle spasm in the intercostal muscles or diaphragm Ischemia induced blood shunted to active limbs Peritoneal ligaments from viscera pull on diaphragm with every footstrike Rest apply pressure bend forward breathe deeply tighten abdominals Hypercapnia excessive carbon dioxide in the blood stream typically caused by inadequate respiration Effects of aging Hypocapnia sometimes incorrectly called acapnia is a state of reduced carbon dioxide in the blood It usually results from deep or rapid breathing known as hyperventilation Lung volumes Tidal volume 400 600 ml breath Breathing frequency 12 15 breaths minute Max breathing rate 60 breaths min Residual volume air left after max exhalation