oxygen consumption during recovery

Question 1

define EPOC

Answer 1

amount of oxygen consumed during recovery above that which would have been consumed at rest during the same time

Question 2

what does EPOC stand for

Answer 2

excess post-exercise oxygen consumption

Question 3

recovery

Answer 3

involves returning the body to its pre-exercise state

Question 4

explain the breathlessness that occurs after exercise

Answer 4

= EPOC

• after exercise oxygen consumption remains high in comparison with oxygen consumption at rest.
• This is because extra oxygen needs to be taken in and used to try and help the performer recover

Question 5

2 main component of EPOC

Answer 5

1. fast component

2. slow component

Question 6

fast component

Answer 6

= uses extra oxygen that is taken in during recovery to restore ATP and PC stores and to re-saturate myoglobin

• complete restoration of PC = takes up to 3 minutes but 50% of stores can be replenished after only 30 seconds in which approx 3 litres of oxygen are consumed
• myoglobin has a high affinity for oxygen. it stores oxygen in the sarcoplasm that has diffused from the haemoglobin in the blood. After exercise, oxygen stores in myoglobin are limited. The surplus of oxygen supplied through EPOC helps replenish these stores, taking up to 2 minutes and using approx 0.5litres of oxygen

Question 7

what are the several functions of the slow component

Answer 7

1. removal of lactic acid
2. maintenance of breathing and heart rates
3. glycogen replenishment
4. increase in body temperature

Question 8

how does the slow component work to: removal of lactic acid?

Answer 8

• when oxygen is present, lactic acid can be converted back into pyruvate and oxidised into carbon dioxide and water in the inactive muscles and organs (then used by muscles as an energy source)
• transported in the blood to the liver where it is converted to blood glucose and glycogen (cori cycle)
• converted into protein
• removed in sweat and urine

Question 9

what can you do to accelerate the removal of lactic acid

Answer 9

cool down
- because exercise keeps the metabolic rate of muscles high and keeps capillaries dilated which means oxygen can be flushed through, removing the accumulated lactic acid

Question 10

when does the slow replenishment stage of recovery begin…

Answer 10

• as soon as lactic acid appears in the muscle cell and will continue using breathed oxygen until recovery is complete
• this can take up to 5-6 litres of oxygen in the first half hour removing up to 50% of lactic acid.

Question 11

how does slow component work to: maintenance of breathing and heart rates

Answer 11

• maintaining breathing and heart rates requires extra oxygen to provide the energy needed for the respiratory and heart muscles. This assists recovery as the extra oxygen is used to replenish ATP and PC stores, re-saturate myoglobin and remove lactic acid therefore returning the body back to its pre-exercise state.

Question 12

how does slow component work to: glycogen replenishment

Answer 12

• replacement of glycogen stores depends on the type of exercise undertaken and when and how much carbohydrates are consumed following exercise.
• may take several days to complete the restoration of glycogen after a marathon, but in less than an hour after high duration short intensity. Bc a significant amount of glycogen can be restored as lactic acid and is converted back to blood glucose and glycogen in the liver via the cori cycle.

2 nutritional windows for optimal recovery after exercise

• > 30 mins after carbs : protein 4:1 3:1
• this combination helps the body to re-synthesise muscle glycogen much more efficiently than just consuming carbs on their own

-> 1-3 hours after exercise and a meal high in protein, carbohydrate and healthy fat should be consumed.

Question 13

how does slow component work to: increase in body temperature

Answer 13

when temps remains high, respiratory rates will also remain high and this will help the performer take in more oxygen during recovery.
- however, extra oxygen is needed to fuel this increase in temperature until the body returns to normal

Question 14

explain the effects of exercise intensity on EPOC (4)

Answer 14

• as exercise intensity increases the need for and length of recovery also increases
• during low intensity aerobic exercise a smaller sub-maximal oxygen debt occurs than during high-intensity anaerobic exercise where a larger maximal oxygen deficit occurs
• so athletes require more time for recovery and a higher consumption of oxygen after exercise (EPOC) in order to recover by re-saturating myoglobin with oxygen, supplying energy for the cardiorespiratory system and removing lactic acid from muscles.