Erddig Muddy Trainers

Energy Systems

 

We will describe these by imagining a run

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There are three of these energy systems and which of them are used depends on the internsity of the effort.

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In our normal steady running when we stay at a level we can comfortabley sustain for a period of time we are using the aerobic energy system. Muscle cells break down glucose using oxygen to produce carbon dioxide and water and this produces enough energy for our muscle cells to keep workingat this level. Note that this depend on the abilty to supply oxygen to the muscle cells and as we get fitter the body is able to supply more oxygen and therefore the level of intensity we can sustain will go up

 

Let us imagine we now put in a short sprint. The extra energy we need can be supplied in the short term by supplies of ATP which exist at all tiimes in cells and are available when extra energy demands are made on the cell.  There is enough of this ATP to last around 20 seconds of near maximum effort. This is called the phosphogenic system as ATP contains phospahate.

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If the sprint is sustained for longer than this at the end of the the race or we are running up a long hill then a third way of supplying energy can be used. This is to break down glucose incompletely without using oxygen. This produces ATP which can be used for energy and the glucose is broken down to lactic acid.

As the lactic acid builds up in the muscle cells then this makes the muscles tire and also produces what is called 'the burn. It hurts and our running becomes laboured. After this period of sustained efffort breathing remains raised for a while becasue the lactic acid has to be broken down to carbon dixide and water and this requries oxygen. This is called the anaerobic energy system becuse energy can be produced without oxygen but as you can see only for a short time.