KIN 3306 1st Edition Final Exam Study Guide The final will be comprehensive and will consist of 60 MC no short answer questions and 2 essays Lecture 8 March 7 Heart Rate is how many times the heart is beating per minute It is useful for exercise prescription monitoring individual sessions tracking training progress and seeing if one is overtraining Heart rate is a physiological way to track progress There are different types of heart rate such as heart rate resting heart rate maximum heart rate and steady state heart rate Resting Heart Rate depends on how trained one is a trained individual s resting heart rate would be in the 50s or 60s Maximum Heart Rate this is the highest your heart rate can get when you are doing maximal intensity exercise This is difficult to measure so we use the equation of 208 0 7 x age Steady State Heart Rate this is how many times the heart will beat per minute during stead state exercise Stroke Volume is the volume of venous blood being returned to the heart It is how much blood the heart is pumping per beat which is basically how much the heart squishes out The stroke volume will increase during exercise Cardiac Output Q is HR x SV It is how many times the heart beats per minute times how much blood is coming out per pump Resting Q is equal to 5L minute with maximum Q equaling around 20 40L min during exercise The more trained you are the higher Q will be Hemodynamics is the study of the interrelationship between pressure resistance and flow Blood flows from high pressure ventricles to low pressure aorta pulmonary artery and is affected by vasoconstriction and vasodilation Blood does not equally flow everywhere because there is resistance that happens in parts of the body that directs how much is going where Vasoconstriction creates higher pressure so that the blood will not want to go there versus vasodilation where the blood wants to go because there is low pressure During exercise blood flow to every where but the active skeletal muscle is reduced Autoregulation of Muscle Blood Flow during Exercise When we exercise the SNS is activated which initiates full body vasoconstriction whereas at the active skeletal muscle different by products will signal for vasodilation locally So basically we get blood to the muscles through sympathetic whole body vasoconstriction and local vasodilation Cardiovascular Changes during Exercise Systolic blood pressure and mean arterial pressure increase during exercise but diastolic blood pressure remains pretty constant As the exercise intensity increases HR and Q will also increase SV will increase up to a certain intensity around 50 of the maximum intensity and then remain constant from there with an exception for endurance athletes whose SV will continue to increase up to the VO2 max Frank Starling Mechanism says that an increase in end diastolic volume will equal an increase in stroke volume Basically the more blood that is in the heart the more you will be able to pump Contractibility helps with this because the ventricles can contract more because it can expand more Also vasoconstriction helps pump blood back to the heart In addition to that there is also the muscle pump which is the fact that the contraction of the muscles will help squeeze blood back to the heart when exercising or even just walking There is also the respiratory pump where the respiratory muscles help pump blood back to the heart as well All of these mechanisms help bring blood back to the heart quicker Cardiovascular Drift during Long Duration Exercise During long duration exercises greater than 60 minutes at a fixed intensity around 65 85 of max we see a cardiovascular drift This drift is when your HR creeps up a bit even though you are doing steady state exercise This is possibly caused by an increase in body temperature dehydration and a decrease of venous return to the right side of the heart All of this makes it harder to get blood back to the heart Exercise Response to Acute Exercise During acute exercise there is a decrease in stimulation of the vagus nerve that controls HR There is also an increase in stimulation of the cardiac accelerator nerves which stimulate HR There is a change in blood flow in which vasodilation occurs to get blood to the active skeletal muscles and vasoconstriction occurs in the areas on inactive tissue Lecture 9 April 14 The Red Blood Cell is what transports oxygen within the blood throughout the body It contains hemoglobin which roughly transports around 98 of oxygen RBC s do not have a nuclei or a mitochondria so they must make ATP using anaerobic glycolysis 2 3 DPG is a byproduct of this reaction When training at high altitude we will see a high level of DPG in blood and this will decrease the bond between hemoglobin and O2 which will allow us to extract more O2 At sea level there is not much of an effect Blood is composed of plasma and formed elements Plasma is the liquid portion and it contains ions hormones proteins and nutrients Formed Elements include the red blood cells which carry oxygen white blood cells which provide immunity and platelets which provide clotting factors Hematocrit is the percentage of red blood cells in the blood On average men have a hematocrit of 45 and women have a hematocrit of 40 Having a higher hematocrit is beneficial Hemoglobin has four subunits which means that there can be a maximum of four O2 molecules bound to it Binding increases the affinity so once it binds to one O2 molecule that will increase the amount that it wants to grab the second O2 molecule Also once it has four it will hold tightly to them Once hemoglobin unloads one the more readily it will unload the rest It follows the O2 Hemoglobin Dissociation Curve Myoglobin is similar to hemoglobin except for the fact that it is in the muscle It is basically a storage place for O2 in the muscle The difference is that myoglobin holds onto O2 longer so it has a higher affinity only until it gets to a significantly lower PO2 then it will start releasing O2 Exercise and Hemoglobin Dissociation A couple of things will affect the curve during acute exercise Body temperature and acidity are the main two things When body temperature increases during exercise the bond strength between hemoglobin and oxygen will decrease which will make hemoglobin let go of its O2 easier which is beneficial As for pH we have acid as a by product of exercise so the blood pH will drop and that will decrease the bond strength between hemoglobin