EPOC

Question 1

What is EPOC

Answer 1

Excess post oxygen consumption(oxygen debt)
- The volume of oxygen required post exercise to return the body to it’s pre-exercise state

Question 2

What happens after exercise

Answer 2

• Body in state of fatigue
• Myoglobin has depleted O2 stores
• ATP,PC and glycogen stores are depleted
• High levels of lactic acid
• Feelings of exhaustion

Question 3

work:relief + O2 supply =

Answer 3

Breakdown and removal of lactic acid

Question 4

What is the aim of the recovery process

Answer 4

Primary aim is to return the body to a pre exercise state where:
- Myoglobin is saturated
- Fuel stores fully restored
- Blood and muscle fibres fully free of by-products

Question 5

What happens during the fast alactacid component of recovery

Answer 5

• ATP, PC + glycogen stores are depleted as well as myoglobin
• First stage of recovery
• Accounts for 10% of EPOC (1-4 litres of O2)
• Replenishment of blood and muscle with oxygen
• Resynthesis of ATP (in the muscle) and PC stores

Question 6

What happens during the replenishment of blood and muscle oxygen

Answer 6

• During exercise O2 is dissociated from the haemoglobin and myoglobin
• Within the first minute of EPOC, O2 is restored/resaturated in the bloodstream
• Within 3 minutes oxy-myoglobin links are restored

Question 7

What happens during the resynthesis of ATP and PC stores

Answer 7

• ATP and PC stores are depleted
• Within the first 3 minutes, aerobic energy production continues, providing energy for ATP and resynthesis
• 30 seconds to restore 50%
• 3 minutes for full (100%) restoration

Question 8

What happens during the slow lactacid component of recovery

Answer 8

• Second stage of recovery
• Approx 5-8 litres of O2 is required to complete the more complex and time-consuming return to pre exercise state
• Provision of the energy to maintain ventilation, circulation and body temp
• Removal of lactic acid and replenishment of glycogen

Question 9

What happens during ventilation and circulation

Answer 9

• During exercise respiratory rate, depth and heart rate increases
• The energy cost of continued aerobic energy production is 1-2% of EPOC

Question 10

Body temp in slow lactacid

Answer 10

• For every 1 degree celc rise in body temp,metabollic rate increases by 13-15%
• Post exercise the elevated temp remains, potentially for several hours post vigorous exercise
• Accounts for as much as 60-70% of slow lactacid component of EPOC

Question 11

What happens during the removal of lactic acid and replenishment of glycogen

Answer 11

• Post exercise, LA is readily converted back to pyruvic acid and is either oxidised or converted into glycogen
• Approx 50-75% of PA is oxidised into the mitochondria
• Approx 10-25% of PA is reconverted into glucose
• Small amounts of pyruvic acid (PA) are also converted into protein by the Cori cycle in the liver and removed from the body in sweat and urine
• OBLA + muscle fatigue
• buffering capacity = cope with lactic acid
• hydrogen ions combine with lactic acid to form carbonic acid… can be broken down into CO2 + H2O for removal at lungs