The Short Long Term Effects of Exercise on

The Short & Long Term Effects of Exercise on the CV System Unit 2 – The Physiology of Fitness

Short Term Effects Works harder to meet the body’s demand for more O 2 & nutrients Increase in heart rate ( heart beats faster) Increase in stroke volume (heart beats harder)

Short Term Effects • Heart Rate Anticipatory Response HR increases before you start to exercise in anticipation to prepare for extra demands HR is controlled by nerves – contraction of cardiac muscle & chemicals in blood (adrenaline) • Activity Response Start to exercise – brain detects extra CV activity & sends messages via nerves to make the heart beat faster & stronger

Short Term Effects • Increased Blood Pressure Because HR & stroke volume has increased, there is more blood pumping through the blood vessels • Redirection of Blood Flow To increase blood flow to working muscles the body redirects blood from other areas by opening and narrowing certain arteries & arterioles Vasodilation – opens up arteries/arterioles Vasoconstriction – Narrows arteries/arterioles

Long Term Effects • Cardiac Hypertrophy Same as skeletal muscles your cardiac muscle (heart) gets bigger and stronger. The wall of the left ventricle gets thicker which increases the strength of it’s contractions. This leads to. . • Increase in stroke volume Because the heart is bigger & the contractions are stronger your heart can pump more blood per beat

Long Term Effects • Increase in Cardiac Output Because your stroke volume has increased you will pump more blood per minute • Decrease in Resting Heart Rate Because your heart can pump more blood per beat, it doesn’t need to beat as many times to pump the same amount of blood • Capillarisation To cope with the increase in blood flow, your capillary network develops. You develop more capillaries and these get bigger

Long Term Effects • Increase in Blood Volume More & bigger capillaries = able to hold more blood in the body • Decrease in Resting Blood Pressure CV system = more efficient & more blood means there is less pressure on the walls of the blood vessels

Long Term Effects • Decrease in Recovery Time Heart rate recovery is how low your HR falls in the 1 st minute after exercise. The fitter you are the quicker your HR returns to normal after exercising, because the CV system is better at coping with exercise • Increase in Aerobic Fitness CV system develops to be better at getting more O 2 to the muscles quicker = increases your ability to do aerobic activity