EnergyThe body needs energy for basicbodily functions and activity duringyour whole life.This includes breathing, sleeping,digesting, sitting in a chair, sprintingfor a bus, and everything else you doday and night.
Adeonsine Triphosphate (ATP)A chemical compound.Is the energy source for all musculareffort.Sources of ATP: Carbohydrate, fatand protein.
CarbohydrateWhen digested is broken down toglucose and stored as glycogen inthe muscles and liver.Glycogen can provide the energy forATP production under both anaerobic(no oxygen required) and aerobic(oxygen required) conditions.
FatMajor source of energy for long termactivity.Is used to meet sub-maximal energydemands.During rest conditions, fat producesthe majority of the required ATP.
ProteinOnly minimally contributes to ATPproduction.Is only used in severe circumstances(such as a marathon or starvation)when the body has severely depletedit’s supplies of carbohydrate and fat.
Energy from ATPATP is stored in limited quantities in the muscle,so each muscle fibre must be able to create it’sown from the food fuels.ATP is an adenosine molecule with threephosphate molecules attached.For release of energy, one phosphate moleculebreaks off, releasing energy and creatingadenosine diphospate (ADP).As long as there are sufficient energy substratethis process can be reversed with the use of foodfuels and ATP is rebuilt with the addition ofanother phosphate molecule.
Three Energy SystemsPhosphate, Anaerobic Glycolysis andAerobic Energy All three pathways operate at onetime.The contribution of each variesdepending on the intensity of theactivity.
Phosphate Energy SystemProvides the bulk of ATP duringpowerful or explosive efforts.May be a once off movement such asjumping or ongoing such as a 100msprint.Lasts for about 10 seconds ofmaximal effort.
Anaerobic Glycolysis SystemAlso known as the Lactic AcidSystem.Provides energy in high intensity,sub maximal efforts.Muscle stores of glycogen are brokendown to resynthesise ADP.Lasts from around 10 seconds until60 seconds of exercise.
Aerobic Energy SystemAlso known as aerobic glycolysis.Provides the bulk of energy for submaximal efforts and recovery.Contributes to all activities fromabout 1 minute onwards.Fat becomes a significant contributorto ATP production.Can operate for an unlimited workperiod.
ATP production – different exertion conditions The length and intensity of physical exertion determine which of the energy systems is dominant. As activity time increases, the influence of the aerobic system on ATP production also increases.