Energy transfer during short duration/High intensity exercise Flashcards
What causes lactate accumulation
Lactate accumulation occurs when there’s not enough oxygen in the muscles to break down glucose and glycogen.
Lactate threshold
The point during exercise at which lactic acid quickly accumulates in the blood
What does OBLA stand for
Onset Blood Lactate Accumulation
OBLA
The point when lactate levels go above 4 millimoles per litre
What does measuring OBLA give an indication of
Endurance capacity
How is lactate threshold expressed
Percentage of VO2 max
Why does training have a limited effect on VO2 max
Because it is genetically determined
What happens to out lactate threshold teh fitter we are
The fitter we are, the higher our lactate threshold as a % of VO2 max and hence the harder we can work
What test can measure OBLA
Multi stage fitness test
What are the 5 factors that can affect the rate of lactate accumulation
- Exercise intensity
- Muscle fibre type
- Rate of blood lactate removal
- Respiratory exchange ratio
- Fitness of the performer
How does exercise intensity affect lactate accumulation
The higher the exercise intensity, the greater demand for energy and the faster OBLA occurs
How does muscle fibre type affect lactate accumulation
Slow twitch muscle fibres produce less lactate than fast twitch fibres
How does rate of blood lactate removal affect lactate accumulation
If lactate production increases, then lactate will start to accumulate in the blood until OBLA is reached
How does respiratory exchange ratio affect lactate accumulation
When glycogen is the preferred fuel, this ratio has a value close to 1:0 and there is a greater chance of the accumulation of lactate
How does fitness of the performer affect lactate accumulation
A person who trains regularly will be in a better position to delay OBLA as adaptions occur to trained muscles (Increased mito and myoglobin)
Why do elite sprinters and power athletes have a much better anaerobic endurance
Their body has adapted to cope with higher levels of lactate
Buffering
Soaks up hydrogen ions that cause the acidity.
What will buffering allow
This means that athletes will be able to work at higher intensities for longer before fatigue
What are the 7 factors that affect VO2 max
- Physiological
- Training
- Lifestyle
- Body composition
- Gender
- Age
- Genetics
Why does training affect VO2 max
VO2 max can be improved by up to 10-20% following aerobic training
Why does lifestyle affect VO2 max
Smoking, sedentary lifestyle, poor diet and poor fitness can all reduce VO2 max
Why does body composition affect VO2 max
A higher % of body fat decreases VO2 max
Why does age affect VO2 max
As we get older our VO2 max declines as our body systems become less efficient
Why does gender affect VO2 max
Men generally have 20% higher VO2 max than women
Why does genetic affect VO2 max
Inherited factors of physiology limit impossible improvement
Why does physiological affect VO2 max
- Increase Q
- Increase SV/EJ
- Greater HRR
