Energy Systems

The human body is made to move in many ways• Quick and powerful• Graceful & coordinated• Sustained for many hours• Quick movements-lasts a few seconds• Reduced speed-lasts for several minutes• Reduced intensity(50%)-lasts for several hours

Energy System

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The body uses different energy systems for each activity dependent upon the capacity to produce energy

The human body has three main systems for producing energy for our physical activity1. Anaerobic Alactic2. Anaerobic Lactic3. Aerobic

Cells in the body need energy to function

FOOD=ENERGY (E)

Each system works independently or in unison with the others depending on the type of activity we are doing

Each these systems provide the body with energy by producing ATP (energy currency)

Cells don’t get Energy directly from food, it must be broken down into:

ATP- Adensosine TRI phosphate

ATP = a form of energy one can immediately use, it is needed for cells to function & muscles to contract

Our body cant carry the amount of energy needed, so has systems in place to produce ATP

Our body uses food/fuel to help produce the ATP required for our bodies needs

• Glucose = Glycogen (muscle & liver)

• Fatty Acids = Body fat

• Amino Acids = Growth, repair or excreted as waste

ATP is stored in small amounts, therefore the rest is stored as:

• ATP (2-3 seconds)• ATP-CP Energy System (8-10 seconds)

• Anaerobic Energy System (2-3 minutes)

Predominant Energy

Pathways

Aerobic Energy System (3 minutes +)

ATP is stored in the muscle & liver for “Quick Energy”• Nerve impulses trigger breakdown of ATP into ADP• ADP = Adenosine Diphosphate & 1 Phosphate• The splitting of the Phosphate bond = Energy for workEx. Muscle Contraction, Moving hand from a hot stove, Jumping & Throwing

ATP-CP Energy System

For contractions to continue… ATP must be REBUILT

This comes from the splitting of CP (Creatine Phosphate a Hi energy source, automatic)

When ATP is used – it is rebuilt – as long as there is CP

Energy released from CP breaking down, resynthesizes the ADP & P

ATP-CP = 8-10 sec. of Energy

The usefulness isn’t the AMOUNT of Energy but the QUICK & POWERFUL movements

For longer periods of work = The Aerobic & Anaerobic Energy System must be utilized

REMEMBER – only small amounts of ATP are stored = only 2-3 sec. of Energy

• Without oxygen = Activities that require a large burst of energy over a short period of time• Anaerobic Glycolysis = Production of ATP from Carbohydrates without oxygen (breakdown of glucose) Since glycogen is stored in the muscle & liver, it is available quicklyThis system provides ATP when ATP-CP runs out

Anaerobic Energy System

1. The process to produce ATP is not as fast as ATP-CP, which makes muscle contraction slower

2. When oxygen is not present the end product of glycolisis is lactic acid, which causes the muscles to fatigue

3. Anaerobic Glycolisis is less efficient in producing ATP than Aerobic Glycolisis, BUT is needed for a large burst of energy lasting a few minutes

Again, ATP-CP lasts for a few seconds, the Anaerobic Energy System allows for 2-3 minutes of work

Glucose = 2ATP + 2LA (digested component of carbohydrates)

Glycogen = 3ATP + 2LA (the storage form of glucose)

Without Oxygen

Glucose + O2 = 36ATP + H2O + CO2Fatty Acids + O2 = 129ATPBody Fat is a great source of ENERGY

With Oxygen

Oxygen Deficit = The body can not supply enough O2 to the muscles that the muscles demand

• When the muscle does not get enough oxygen, exhaustion is reached causing immediate and involuntary reduction in intensityOxygen Debt = “pays back” the deficit recovery time

aerobic Energy System• With Oxygen = Using large muscle groups continuously over a period of time

• Aerobic Glycolisis & Fatty Acid Oxidation = The production of ATP from Carbohydrates & Fat

1. O2 enters the system, stopping the breakdown of glycogen to lactic acid

2. With oxygen, glycogen breaks down into: ATP + CO2 + H20

3. These byproducts are easier to get rid of CO2 is expelled by the lungs H20 is used in the muscle

4. Anaerobic Energy System = Carbohydrates are the only fuel source

5. With prolonged exercise, Carbohydrates are the first fuel choice, as exercise continues, FAT becomes predominant

6. Protein is not a main fuel source except in an emergency

Each system plays an important role in energy production

This gives us a variety of movements

The systems interact to supply Energy for the activity