2. What is Oxygen Uptake? What is VO 2 Max?

3. OXYGEN UPTAKE - VO 2 amount of oxygen consumed per unit of time (usually 1 minute) expressed as VO 2 mean value at rest = 0.2 to 0.3 l min -1 VO 2 increases proportionally to work intensity up to a maximum value - called VO 2 max

4. DRAW A GRAPH TO ILLUSTARTE THE DIFFERENCE BETWEEN A TRAINED AND UNTRAINED ATHLETE IN RELATION TO THEIR VO2 MAX

5. Trained Athlete Untrained Athlete

6. AEROBIC CAPACITY the ability to do physical work which is dependant on the aerobic mechanism of energy supply STEADY STATE the demands of the body for oxygen is balanced exactly by oxygen uptake

7. FACTORS AFFECTING VO2 MAX Availability of O 2 in the tissue – Is haemoglobin saturated with oxygen at muscle tissue – Varies individual to individual – Myoglobin in muscle cells is fully saturated with O 2 (has sufficient recovery time elapsed?) reduction in VO 2 max will cause decline in aerobic performance Age – reduction by 10% per decade Aerobic training can improve by 10% Women tend to have greater reductions in VO2 max

8. DRAW A GRAPH TO ILLUSTARTE VO2 MAX AGAINST AGE FOR TRAINED & UNTRAINED MALES

9. ONSET OF BLOOD LACTATE ACCUMILATION OBLA as work intensity increases lactic acid starts to accumulate above resting values at a certain point this produces muscle fatigue and pain the resultant low pH inhibits enzyme action and cross bridge formation hence muscle action is inhibited physical performance deteriorates this point governs the lactic aerobic threshold trained athletes begin OBLA at higher work intensities and higher values of VO 2 max than untrained people

11. FOOD FUEL USAGE this depends on : EXERCISE INTENSITY EXERCISE DURATION SOURCES OF FUELS main source of CHO for muscular energy during exercise is glucose derived from stored muscle and liver glycogen lack of CHO fuel is the limiting factor for aerobic endurance performance main source of fat for muscular energy during exercise is free fatty acids (FFA) derived from triglycerides stored as adipose tissue under the skin and in muscle tissue

12. FOOD FUEL USAGE FOR AEROBIC ACTIVITY

13. ADAPTATIONS TO AEROBIC CAPACITY cardiovascular system becomes more efficient more haemoglobin is created and is available in blood for oxygen transport pulmonary systems become more efficient lung volumes increase slightly, greater volumes of air can be breathed per breath Improved oxygen recovery Hence reduction in DOMS More myoglobin is created in muscle cells More and bigger mitochondria in muscle cells