| Question | Answer |
| alterial-venous oxygen difference (a-vO2 diff) | the difference in the oxygen content of the blood (ml/100ml) as measured when it leaves the heart after being oxygenated by the lungs versus upon its return to the heart (i.e., the amount of oxygen extracted by the body). |
| autoregulation | the name given to a bodies ability to control the arteriole blood flow at localized areas of the body. This occurs due to chemical changes at the local level such as lowered oxygen levels which cause the arteriole to dilate. |
| cardiac cycle | all the events of the heart operation between two consecutive heart beats. |
| cardiac output (Q) | the total volume of blood pumped by the heart per minute. The product of heart rate and stroke volume. |
| end-diastolic volume | the volume of blood contained in the ventricle at the end of the diastole (prior to its contraction). |
| end-systolic volume | the volume of blood contained in the ventricle at the end of the systole (just after its contraction). |
| extrinsic neural control | control of blood flow directed by sympathetic nervous system which redirects blood flow from areas of low need to areas of high need by constricting or relaxing arterioles |
| hematocrit | the ratio of blood volume composed of cells or formed elements to total blood volume. |
| hemoconcentration | the name given to the effect of increased hematocrit due to loss of blood plasma during exercise |
| hemoglobin | a molecule of the red blood cell which oxygen binds to allowing for the transport of oxygen through the blood stream. |
| hypertension | chronically elevated blood pressure above the norm. |
| maximum heart rate | the highest heart rate attained during an all-out exercise effort to exhaustion |
| steady-state heart rate | the heart rate attained within a few minutes and sustained during the duration for a particular level of physical exercise. |
| stroke volume | the volume of blood ejected from the left ventricle per contraction. |
| anaerobic threshold | the respiration point where the volume of CO2 produced increases at a higher rate when compared to the O2 volume consumed |
| expiration | the process where gas is expelled from the lungs |
| external respiration | the name given to the process of bringing air into/out of the lungs and the gas exchange (CO2 and O2) inside the lungs. |
| hyperventilation | an increase in ventilation occurring without need from a metabolic perspective |
| inspiration | the active process where the diaphragm and intercostal muscles contract to increase the volume of the thoracic cage which causes a measure drop in the lungs allowing outside air to enter |
| internal respiration | the name given to the transport of gases (CO2 and O2) in the circulatory system and the gas exchange in the tissues |
| pulmonary diffusion | the gas exchange in the lungs in which O2 is absorbed and CO2 is removed from the blood |
| pulmonary ventilation | another name for breathing |
| respiratory centers | the location in the medulla oblongata which control the rate and depth of breathing |
| respiratory membrane | the thin tissue area in the lung where the gas exchange occurs in the lungs |
| Valsalva maneuver | a technique used to increase blood pressure during resistance exercise where a person tries to exhale while the mouth, nose and glottis are closed. |