KIN 3306 1nd Edition Lecture 3 Outline of Last Lecture I Overview II Energy Pathways III Protein Metabolism IV Aerobic Exercise and O2 Consumption V Aerobic Exercise and O2 Consumption continued VI Aerobic Exercise and O2 Consumption continued VII Energy Expenditure VIII Fitness Level VO2max IX Bruce Protocol X VO2max Data XI Substrate Utilization XII Respiratory Exchange Ratio XIII Respiratory Exchange Ratio XIV The Crossover Effect XV Oxygen Consumption Limitation XVI Exercise Transition XVII Reset Transition XVIII Possible Explanations for EPOC 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 XIX Why is Lactate produced during Anaerobic Exercise XX Lactic Acid XXI Bicarbonate System XXII Lactate Threshold XXIII Lactate Threshold continued XXIV Does Lactic Acid Cause Fatigue XXV Cytosolic Redox Potential XXVI Causes of Fatigue XXVII Glycogen Depletion XXVIII Glycogen Depletion and Exercise Intensity XXIX CHO and Glycogen Storage XXX CHO Loading Outline of Current Lecture I Overview II Regulation of Glucose Metabolism III Glucagon IV Epinephrine and Norepinephrine V Cortisol VI Short Duration Exercise VII Long Duration Exercise VIII Blood Glucose Exercise Response IX Insulin X Insulin Blood Glucose Exercise XI Regulation of Fat Metabolism XII Cortisol XIII Epinephrine and Norepinephrine XIV Growth Hormone XV Fat Metabolism During Exercise XVI Regulation of Blood Plasma XVII Aldosterone XVIII Signal for Aldosterone Release XIX Renin Angiotensin Aldosterone XX ADH XXI ADH Loop XXII Maintenance of Blood Plasma Current Lecture I Overview a Hormones that mediate specific actions during exercise i Regulation of glucose metabolism ii Regulation of fat metabolism iii Regulation of blood plasma b The endocrine system plays a role in coordinating and making sure the substrates are available when they need to be available c Blood plasma is the water part and it s important because it s the fluidity of the blood If it becomes too viscous its hard for our body to pump blood II Regulation of Glucose Metabolism a Controlled by 5 hormones i Insulin rest only 1 Type 1 diabetics don t produce insulin ii Glucagon 1 Does the opposite of insulin iii Epinephrine 1 Adrenaline iv Norepinephrine 1 Noradrenaline v Cortisol 1 Stress hormone b During exercise blood glucose is affected by 3 factors i Liver release of glucose ii Muscle uptake of glucose iii Dietary intake of glucose c The point of this is making sure your blood glucose concentration is maintained at resting levels The liver is a storage place for glycogen It will get broken down and released into the blood The dietary intake of glucose refers to whether or not you are on a high carb diet or low carb diet etc III Glucagon a Secretion Site Pancreas alpha cells b Action Cause liver glycogen breakdown and glucose release to blood c Exercise Response Positively correlated to exercise intensity d Effect of Chronic Exercise Decrease at given intensity compared to untrained individual e Glucagon is the opposite of insulin Insulin makes cells take up glucose so glucose causes the liver to breakdown the supply of glycogen and release it to the blood As you start exercising glucose is going to secrete and that correlates to exercise intensity Training over time There will be a smaller glucagon response to the same stimulus Here the crossover point will shift IV Epinephrine and Norepinephrine a Secretion Site Adrenal medulla and SNS b Action Works with glucagon c Exercise Response positively correlated to exercise intensity intensity 50 75 of max effort d Effect of Chronic Exercise Decrease at given intensity compared to untrained individual e AKA catecholamines AKA adrenaline These are flight or flight response hormones SNS sympathetic nervous system is also known as the fight or flight system while the PNS parasympathetic nervous system is known as the resting and digesting nervous system The harder you run the greater amount of catecholamines are released to the blood if it is over 50 of the max The more trained you are the more able you are to use fat metabolism at higher intensities V Cortisol a Secretion Site Adrenal cortex b Action Increase in protein catabolism increase blood amino acids for gluconeogenesis c Exercise Response Positively correlated to exercise intensity 80 max effort d Effect of chronic exercise Slight increase at given intensity compared to untrained individual e AKA stress hormone Amino acids will be taken to the liver and converted to glucose gluconeogenesis Cortisol plays a role in fat metabolism VI Short Duration Exercise a High intensity i Greater catecholamine release ii Greater release of glucose from liver b 40 50 increase in blood glucose c Replenishes muscle glycogen stores d After sprints blood glucose goes up because of the intensity and the rush of liver glycogen release Once you rest in between sprints the blood glucose that is available is up took by the muscles to replenish glycogen stores Insulin signals muscle uptake of glucose so you just maintain a high blood sugar if you re diabetic VII Long Duration Exercise a Glucose production demand b Liver glycogen stores are a limiting factor c Blood glucose concentration may decrease d Glucagon cortisol gluconeogenesis e CHO intake beneficial f As you train as the demand goes along it is met by this hormonal response You have what you need So your glucose levels should stay level Cho during exercise can be important like eating jellybeans and Gatorade throughout exercise It will keep your blood glucose from dropping too low VIII Blood Glucose Exercise Response a All hormones work together to maintain glucose levels at or close to resting values This refers to duration not intensity Glucagon spikes in the beginning and flattens out Cortisol responds in the beginning and tapers off because we re under 80 max Catecholamines keep rising IX Insulin a Secretion Site pancreas beta cells b Action Glucose uptake by muscle at rest regulating blood glucose concentration c Exercise Response Not released during exercise receptors more sensitive thus less insulin required d Effect of Chronic Exercise No exercise response e The primary controller of glucose is insulin It signals the cells to take up glucose During exercise there is not a release of insulin and so it can drop off X Insulin Blood Glucose and Exercise XI Regulation of Fat Metabolism a Controlled by 5 hormones i