Question

What role does “steady-state” aerobic catabolism play in ATP production? How is it different in HIIT and marathon training?

Answer 1

• Steady-state concept is applied during light exercise where pace and intensity remain same for an extended period of time.
• To attain steady state, oxygen consumption increases upon exercise
• Use of ATP during excercise require continuous ATP resynthesis
• Aerobic metabolism includes the oxidation of glycogen and fatty acids to pyruvate and acetate
• The steady-state oxygen consumption is proportional to the exerted mechanical power.
• Catabolism of carbohydrates to pyruvate and lactate by glycolysis (anaerobic) produces ATP needed during exercise
• ATP requirement is met primarily through aerobic ATP synthesis
• First 1–5 secondsof exercise–ATP through stored ATP and PCr (Phosphocreatine)
• Intense exercise longer than 5 sec–Shift to ATP production via glycolysis
• Events lasting longer than 45 seconds–ATP production through ATP-PC, glycolysis, and aerobic metabolism–
• At 1 min: 70% anaerobic/30% aerobic –At 2 min: 50% anaerobic/50% aerobic

HIIT make your body more effective at using fat as fuel which really helps when you get to the lower body fat levels.