Mini Group Activity: In pairs, what do you think are the short-term effects of exercise on the CV system?! List as many responses as possible and be prepared to feedback to the class(7 minute activity).
Heart Rate increases as you start to exercise and will continue to increase as exercise intensity continues to rise. Stoke Volume (the volume of blood being pumped out per beat) also increases when exercise starts, due to the increase of oxygen demand by the working muscles. Rises during the initial stages of work and then levels off until near maximal levels where it slightly declines due to decreased ventricular filling time. Cardiac output at rest is about 5 lmin -1 and rises to between 20 and 40 lmin -1 depending on the size of the ventricle and resulting stroke volume. The volume of blood delivered to the working muscles increases with every beat of the heart and blood delivery rate increases as heart rate continues to increase. During exercise , blood flow is increased, venous return higher, the heart is stimulated to pump harder and more frequently. WARM-UP increases blood flow and delivery of oxygen in advance of major effort and COOL-DOWN keeps blood flow high, which keeps oxygen delivery, purging of oxygen debt and continuance of metabolic processes to a maximum. As you start to exercise, body temperature also increases. These are immediate responses to exercise. Once the body gets used to changes in the environment or when exercise stops, the body will eventually return to its original resting state. We will take about this on the next slide!
Blood redistribution – rather than overloading the heart, blood is redistributed.
Mini Group Activity: In pairs, what do you think are the long-term effects of exercise on the CV system?! List as many responses as possible and be prepared to feedback to the class(7 minute activity).
Capillaries: This improves the speed at which the oxygen diffuses from the red blood cells to the muscular tissue.
Effects of exercise on body systems Session 1 - The effects of exercise on the cardiovascular system
↑ in Heart Rate ↑ in release of adrenaline ↑ in release of heat ↑ in dilation of vessels ↑ in blood flow to muscles ↑ in Stroke Volume ↑ in Cardiac Output ↑ in Blood Pressure Short Term Responses – CV System