Created by Tim Hodge about 5 years ago
Energy system interplay
Questions that ask you to discuss energy system interplay can come in a number of different forms. Sometimes you can simply be asked to identify a dominant energy system for a particular event, you can be asked to outline the interplay for a long aerobic event, or as seen in the 2011 and 2012 VCAA exams, you were asked to compare and contrast energy system contribution for two events in the same sport. Below are some points to help you answer the question correctly. 1. When any event first starts, all 3 energy systems will be contributing to the overall energy requirements2. There will always be one dominant system3. The dominant system will depend on two factors The duration of the event: The longer an event goes for, the more aerobic in nature (unable to maintain high intensities) The intensity of the event: High intensity events are more reliant on the Anaerobic energy systems 4. Using and understanding the terms rate and yield where appropriate in your responses. ATP-PC has the fastest rate but has a very limited yield due to only small amount of stored ATP and PC stores The Anaerobic Glycolysis system has a fast rate but still a limited yield due to the metabolic by-products produced (H+, Pi, ADP) as a result of only partially breaking down glycogen for ATP. Aerobic is the slowest rate but has a virtually unending yield for most events that people would complete. However, the pay off is we must complete at sub-maximal intensities.
What you need to avoid doing, is simply writing down everything you know about the energy systems and thinking that the assessor will give you marks. Your answer need to be specific to what has been asked and the information that you have been given.If their is a graph or table available, look for moments of Oxygen Deficit (where ever the graph is going up) for hints where there will be an increased contribution form the anaerobic system. Steady States (the graph has plateaued) where it is aerobic and O2 demand equals supply. And lastly EPOC which occurs after an activity where we continue to have higher O2 supply to help remove metabolic by-products and replenish fuel sources.
The best way to prepare for these questions is by doing them. Go through practice exams and pick out the questions on interplay. Alternatively, go to you tube, choose a sport and watch it for a bit. Then write down how the energy systems worked together to produce the energy required. For more info about energy systems, you can also check out the below website. http://www.vcehelp.com.au/energy-systems-power-vs-yield-585/
Energy sysyem interplay