Energy Systems

Muscles require energy to work The energy required by muscles comes from a chemical compound called adenosine triophosphate (ATP) ATP is stored in all muscle cells and is used up in exercise ATP comes from the food we eat In the body there are 3 systems that break down ATP to release energy The system used at any one time depends on the activity being carried out

Energy Systems AerobicAnaerobic Creatine Phosphate ATP-CP Lactic Acid System

1. Aerobic System At rest and in everyday activities energy is released aerobically, i.e. in the presence of oxygen In the aerobic energy system oxygen is present when ATP is made Large amounts of ATP are made without the formation of any fatiguing by-products This type of energy is most suitable for fuelling endurance activities (e.g. any event lasting longer than 5 minutes)

1. Aerobic System Utilises proteins, fats and carbohydrate ( glycogen) for the resynthesis of ATP. The system can be developed by various intensity runs: Run at 50-70% of MHR. This will place demands on the muscle glycogen and liver glycogen. Response= increase in liver glycogen and muscle storage capacity.

1. Aerobic System The second run would be at 60-80% this places demands on the system to cope with lactate production. Response= increase tolerance of lactic acid and quicker removal.

2. Anaerobic System There are 2 energy systems that provide energy without the presence of oxygen The Lactic Acid system is used in activities 30 seconds to 2 minutes long Lactic Acid is a by-product of this energy system and it accumulates in the muscles and blood and causes fatigue In activities less than 10 seconds long a system called the ATP-CP system is used

2. Lactic Acid System Once Creatine Phosphate is depleted the body turns to stored glucose for ATP production. The breakdown of glucose in anaerobic conditions results in lactate and hydrogen ions. The accumulation of hydrogen ions is the limiting factor in 300m- 800m runs.

2. Lactic Acid System Training 5 x 300m 80% with 45 seconds recovery in between. Pushes the lactic acid threshold. 8x 300m with 3 minutes recovery in between- helps aid lactate removal.

3. ATP- CP ATP stores in the body last for approx 2 seconds and resynthesis of ATP from Creatine Phosphate will continue until CP stores in muscles are depleted approx 4-6 seconds. Training. 4-8 seconds of high intensity work near peak velocity. 10 x 30m sprints with 30seconds recovery in between. Repeat 3 times with 3minutes in between each set.