Energy Systemsfor Exercise

Presenter: Ms. Lea Green

The human body is made to move in many ways:

• Quick and powerful• Graceful & coordinated• Sustained for many hours

And is dependent upon the capacity to produce energy

We have a great amount of diversity

• Quick movements-lasts a few seconds• Reduced speed-lasts for several

minutes• Reduced intensity(50%)-lasts for

several hours

The body uses different energy systems for each activity

Cells in the body need energy to function

FOOD=ENERGY (E)

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

down into:

ATP-Adensosine TRIphosphate

ATP = a form of energy one can immediately use, it is

needed for cells to function & muscles to contract

Nutrients that give us energy:

Carbohydrates

FatsProteins

GlucoseFatty acidsAmino Acids

Digestion

Absorbed into the blood & transported to cells

(muscle, liver & nerve)

They are used to produce ATP or stored

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

•Glucose = Glycogen (muscle & liver)

•Fatty Acids = Body fat

•Amino Acids = Growth, repair or excreted as waste

Predominant Energy Pathways

•ATP (2-3 seconds)

•ATP-CP Energy System (8-10 seconds)

•Anaerobic Energy System (2-3 minutes)

•Aerobic Energy System (3 minutes +)

0 sec 4 sec 10 sec 1.5 min 3 min +

Strength – Power:power lift, shot put, golf swing

Sustained Power:sprints, fast breaks, football

Anaerobic Power – Endurance:200-400 m dash, 100 m swim

Aerobic Endurance:Beyond 800 m run

Immediate/short-term Aerobic-oxidativenon-oxidative systems system

ATP-CP Energy System

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 work

Ex. Muscle Contraction, Moving hand from a hot stove, Jumping & Throwing

The ATP Molecule

Adenosine

Adenosine

Energy

a. Adenosine Triphosphate (ATP)

b. The breakdown of ATP:

PP

P

PP P

ATP = ADP + energy for biological work + P

(ADP = Adenosine Diphosphate)

Energy for cellular function

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

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

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

The Immediate Resynthesis of ATP by CP

Creatine

P

Creatine P

Energy

High energy bond

a. Creatine Phosphate (CP)

b. CP = Creatine + energy for resynthesis of ATP + P

Adenosine PP

P

c. ADP + energy from CP + P = ATP (reversal of ATP = ADP + P + energy for work)

Anaerobic Energy System

• 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 quickly

This system provides ATP when ATP-CP runs out

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

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

Without Oxygen

Glucose = 2ATP + 2LA

(digested component of carbohydrates)

Glycogen = 3ATP + 2LA

(the storage form of glucose)

With Oxygen

Glucose + O2 = 36ATP + H2O + CO2

Fatty Acids + O2 = 129ATP

Body Fat is a great source of ENERGY

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 intensity

Oxygen 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

Examples

Anaerobic 70-80% Anaerobic Aerobic

20-30% Aerobic

Wt. Training Stop & Go Sports Jogging

Gymnastics Tennis Marathons

Football SoccerCycling

Baseball Field Hockey Aerobic Dance

Shelton StateWellness Center

PED 223Methods of Instruction