EPOC (HL)

EPOC: the amount of oxygen consumed during recovery above tat which would ordinarily have been consumed at rest in the same time

Oxygen deficit: refers to the different between the oxygen that your muscles demand against the oxygen you can actually provide your muscles

Oxygen debt: known as excess post exercise oxygen consumption (EPOC). After prolonged exercise or anaerobic exercise the body accumulates an oxygen dept. During recovery the body needs to repay this dept requiring extra oxygen to remove the lactic acid.

Changes that occur in muscle cells during exercise

ATP: decrease

Phosphocreatine: decrease

Glycogen: decrease

Triglycerides: decrease

Carbon dioxide: increase

Oxygen/myoglobin stores: decrease

Lactic acid: increase

Water: increase

What does the graph show?

Oxygen deficit: at the start, oxygen demand exceeds supply, so anaerobic systems help provide energy

Steady-state exercise: oxygen supply meets demand

EPOC phase: after exercise, oxygen consumption remains elevated to restore homeostasis

--> the curve gradually decreases as a recovery progresses

Steep initial decline: represents the alactacid phase (fast recovery)

Slower, prolonged decline: represents the lactacid phase (slow recovery)

 

2 Stages of EPOC

Alactic characteristics of EPOC

Lactic Characteristics of EPOC

  • Occurs immediately after exercise (first 2-3 minutes)

  • Replenishes ATP and phosphocreatine stores

  • Resaturates myoglobin with oxygen

  • Accounts for approximately 10% of total EPOC

  • Last from minutes to hours depending on exercise intensity

  • Removes lactic acid via conversion to pyruvate for energy or glycogen resynthesis

  • Regulates body temperature, heart rate and ventilation

  • Restores muscle glycogen and repairs tissues

  • Accounts for approximately 90% of total EPOC