Adaptations to the body

1. Adaptations to the body Miss Lisa Mc Sweeney

2. Lesson Aims Students by this lesson should know.... • The adaptations of the cardiovascular system to exercise • The adaptations of the respiratory system to exercise • The adaptations of the energy system

3. The Cardiovascular System • Heart contracts more often, meaning there is an increase in heart rate (beats per min) • The heart contracts more powerfully- increased stroke volume (the volume of blood pumped out of the heart each beat). • Blood is diverted to muscles (e.g. Is diverted away from the bodies digestive system....why you should not eat before exercise....) • Blood temperature rises • Blood vessels near skin open to allow heat to be lost. • Heart muscle increases in size and strength

4. Cardiac Output (the amount of blood pumped by the heart in one minute. Heart Rate x Stroke Volume = Cardiac Output) • Heart Rate x Stroke Volume = Cardiac Output • Lower resting heart rate as your body becomes used to sustained exercise. • Quicker recovery periods after exercise • Reduced risk of heart disease • Increased number of capillaries • Increased volume of blood and red blood cells

5. The Respiratory System • Increased rate in breathing • Increased depth in breathing (e.g. rise in Tidal Volume- the amount of air breathed in or out of the lungs in one breath). • Increased strength of diaphragm and intercostals muscles • Increased ability of the lungs to extract oxygen from the air. • Increased Vital Capacity (the maximum amount of air that can be forcibly exhaled after breathing in). • Increased amount of oxygen delivered to, and carbon dioxide removed from the body. • The respiratory system deals with taking the oxygen into the body and also with helping remove the waste products.

6. Training over a period of time works by reducing resting heart rate and the breathing rate during exercise • Endurance training can help to slightly increase lung volume (vital capacity increase, meaning you can take more oxygen on board). • This will also help strengthen respiratory muscles as this increase in lung volume will aid lung inflation. • Endurance training will also increase the capillarisation around alveoli in the lungs. This helps to increase the amount of gas exchange in the lungs and therefore, increase the amount of oxygen entering the blood and the amount of carbon dioxide leaving the blood. • Strength training produces few adaptations in that this system uses the anaerobic energy system, whereas the respiratory system is only really concerned with the aerobic energy system.

7. Energy System Adaptations • Aerobic training will increase the number of mitochondria in slow twitch muscle fibres. This allows a greater production of ATP through the aerobic energy system. • Greater amounts of glycogen can be stored in the liver and in the skeletal muscle. • There is an increase in the amount of enzymes required for body fat to be broken down, and more body fat is stored in muscle tissue (e.g. Meaning that more fat can be used as an energy source for exercise participation). • Strength training (which is primarily anaerobic) uses the PC and lactic acid system. • Long term (of more than 8 weeks) strength training increases the bodies tolerance to low levels of pH. As a result energy can be produced by the lactic acid system, and the increased production of lactic acid can be tolerated for longer.