Anatomy And Physiology - Energy For Exercise Flashcards
What is ATP?
The primary source of energy for all cellular processes including muscular contraction during exercise. It consists of adenosine and 3 phosphate molecules.
How is ATP broken down?
ATP is broken down by ATPase into ADP + Pi + energy.
How is ATP resynthesised?
Phosphocreatine is broken down by creatine kinase into phosphate and creatine.
ADP + Pi + energy = ATP
What does the ATP-PC system fuel?
Immediate and fastest way to resynthesise ATP. This anaerobic process primarily fuels short, high-intensity activities such as sprinting powerlifting.
What is the glycolysis system for?
Breaks down glycogen into pyruvate to produce ATP. It is also anaerobic and predominantly fuels moderate to high-intensity exercise lasting a couple of minutes.
What is the aerobic system for?
Uses glycogen or fat to produce ATP with the aid of oxygen. This is the primary system used in low-intensity, prolonged activity such as distance running or cycling.
What type of reaction is the ATP-PC system and where does it occur?
Coupled reaction in the sarcoplasm
How long does each energy system last?
ATP-PC = 10-12s
Glycolytic = 2-3 minutes
Aerobic = potentially forever
What are 5 advantages of the ATP-PC system?
Rapid rate of ATP resythnesis
Provide high-intensity movement
Immediate source of energy
Zero by-products
Do not have to wait for oxygen
What are 2 disadvantages of the ATP-PC system?
Only lasts 10-12s
ATP yield is low; 1:1
What are the advantages of the glycolytic system?
Don’t need to wait for oxygen
Supports high-intensity activity
What are the disadvantages of the glycolytic system?
Produces lactic acid
Limited energy supply
Low yield compared to the aerobic system 1:2
What are the advantages of the aerobic system?
Produces large amounts of ATP 1:38
No harmful by-products
Supports long-duration activities
What are the disadvantages of the aerobic system?
Need to wait for oxygen
Can only produce moderate intensity exercise
What is meant by the interplay of energy systems?
During exercise, all three energy systems contribute to ATP resythesis but the relative contribution of each system depends on the intensity and duration of the activity.
Explain the glycolytic system
Glycogen stored in the muscles and liver is broken down into glucose by the enzyme GPP. Glucose is broke down by PFK into pyruvic acid which releases 2 molecules of ATP. Pyruvic acid is further broken down into lactic acid by LDH.
Explain what happens in the aerobic system
Glycolysis occurs. However instead pyruvic acid is combined with coenzyme A to form acetyl co-enzyme A this then combines with oxaloacetic acid to form citric acid which is then broken down into 4 things in the Kreb’s cycle: ATP x2, CO2, water and hydrogen (also resythesis of oxaloacetic acid). Hydrogen combines with NNAD and FAD to form NADH and FADH which carry hydrogen to the electron transport chain creating potential energy used by ATP synthase to release energy.
What is the role of the cool down phase?
Gradually decreasing exercise intensity to help reduce heart rate and blood pressure. A proper cool down aids the removal of lactic acid faster reducing OBLA and DOMS.
