Embed Size (px)
Citation preview
ENERGY SYSTEMS
• All movements require the muscles to contract.
• For this to happen we need energy.
BACKFLIP ON A SLACK LINE
Freestyle soccer
•To create this energy, chemical energy from the food fuels that we eat is transformed into mechanical energy.
Chemical energy in the body is stored as
Adenosine Triphosphate or (ATP)
Consists of Adenosine and three phosphates
Adenosine Triphosphate or (ATP)
ADENOSINE PHOSPHATE PHOSPHATE PHOSPHATE
HIGH ENERGY BOND
By breaking the bond energy is released.
How is this energy bond broken down?
ADENOSINE PHOSPHATE PHOSPHATE PHOSPHATE
ATPase
ENERGY
This then leaves Adenosine Diphosphate (ADP) and a free phosphate.
As some energy is given off as heat, this reaction is an
Summary
Adenosine Triphosphate
Adenosine Diphosphate Phosphate Energy
ATP ADP P Energy
+ +
+ +
Exothermic reaction
…there is a limited supply of ATP within the muscle cell.Enough for 2-3 seconds of maximal effort.
Unfortunately…
RATE OF ENERGY PRODUCTION
CONCE
NTRA
TION O
F ATP
TIME3 SECS 10 SECS 60 SECS 2 HRS
ATP STORE
Therefore to keep supplying the body with energy, ATP has
to be
resynthesised.
Three energy systems or energy pathways cause the resynthesis of ATP.
1.The ATP-PC or Alactic System
2.The Lactic Anaerobic System
3.The Aerobic System
Intensity and duration of the exercise and whether oxygen is present decides which
system is to be used to generate ATP.
Adenosine Diphosphate And free phosphate
Phosphocreatine / Creatine Phosphate (PC)
ATP-PC System or Alactic System
ADENOSINE
CREATINE PHOSPHATE
PHOSPHATE PHOSPHATE
Creatine Kinase
ENERGY
PHOSPHATE
+ PHOSPHATE
This energy system relies upon another energy rich compound also found in the muscle cell called
Phosphocreatine OR Creatine Phosphate (PC)
1) Phosphocreatine is broken down in the muscle cell by the enzyme creatine kinase.
2) Creatine kinase has been stimulated by the increase in ADP and ‘free’ phosphates resulting from the breakdown of ATP.
ATP-PC System or Alactic System
3) The energy release from the breakdown of phosphocreatine is not used for muscle contraction, but instead is used to rebuild ATP.
4) This then means that ATP can be broken down to release energy.
Summary
ADENOSINE P P P
ATPase
ENERGY
CREATINE P
Creatine Kinase
ENERGY
ADENOSINE P P P
ATP-PC System or Alactic System is exhausted rapidly and can only last for between 3 and 10 seconds.
CONCE
NTRA
TION O
F ATP
TIME3 SECS 10 SECS 60 SECS 2 HRS
ATP STORE
ATP-PC SYSTEM
The system is therefore suited to activities that are high in intensity and short in duration .
The system is therefore suited to activities that are high in intensity and short in duration .
POGO STICK
BELT FLIPS
Advantages of the ATP-PC System to the Athlete
ATP can be resynthesised very rapidly.
PC stores are recovered very quickly, within 2-3 minutes of stopping exerise.
The above means that high intensity can be used once again.
It is an anaerobic process, therefore it doesn’t have to wait 3 minutes for sufficient oxygen to be present.
No fatiguing by-products which could delay recovery.
Some athletes may seek to extend the time they can use this system for through creatine supplements.
Disadvantages of the ATP-PC System to the Athlete
There is only a limited supply of phosphocreatine stored in the muscles.
Only sufficient PC available to resynthesise ATP for approx 10 seconds.
Fatigue occurs when PC levels fall significantly.
Resynthesis of PC can only take place when there is sufficient oxygen available.
How can this system be improved?
Will increase stores of ATP and PC
Will increase the activity of the ATPase and Creatine Kinase
Sprint interval training
Plyometrics
Weight Training (80-85% of 1RM)
In addition some athletes will take creatine supplements to ensure
there is a readily available supply of phosphocreatine in the muscle.
…However
Abdominal cramps
Bloating
Dehydration
Have been reported as side effects by athletes.
Do you allow players to use creatine?
We have banned it.
We don’t discuss our training methods.
Some of our players have used it.
It’s usage is laid down by our medics.
No comment
It is not club policy for players to use it.
No comment
Yes
We do not use any nutritional supplements.
It could be used.
b) Muscle fibre contractions rely upon the release of energy from the breaking down of adenosine triphosphate (ATP).
(i) There is only sufficient ATP within a muscle cell for 1 to 2 seconds of maximal work. Briefly describe how it is possible for a muscle to work continuously for longer periods of time.
(2 marks)
THE EFFECTS OF RELIEF PERIODS FOLLOWING INTERMITTENT EXERCISE ONTHE LEVELS OF ATP-PC STORES IN MUSCLE.
ATP-PC STORES
TIME
WORK RELIEF WORK RELIEF WORK
What conclusions may be drawn about the levels of ATP-PC during
intermittent exercise?
i) ATP-PC stores are exhausted rapidly in high intensity/short duration activities. 8-9 secs in average individualii) Possible to achieve regeneration by up to 50% after 30 seconds restiii) Can regenerate in game by walking or standing but supplies only go back up to approx 90% then down then back up to approx 80% then down etc.
If exercise continues after the 8-10 second
threshold of the ATP-PC system, the muscles must rely on another source of energy to resynthesise
ATP.
LACTIC ANAEROBIC PATHWAY.Once the PC stores have been
depleted within the muscle, ATP must be resynthesised using
another substance...
Glycogen
Carbohydrate is eaten, CHO is made up of starch
Starch is broken down into glucose in the gut
Glucose is passed into the bloodstream and goes to the liver and muscles, where it is
stored as…
Glycogen
Glycogen
Pyruvic Acid / Pyruvate
Phosphofructokinase
This break down of glycogen to release energy is called glycolysis.
As it is performed in the absence of oxygen it is called anaerobic glycolysis.
During this process of glycolysis, energy is released to resynthesise ATP.
Enough energy is released to resysnthesise 2x ATP
As this process takes place without oxygen, the pyruvic acid is converted into…
Lactate (Lactic Acid)
…by the enzyme lactate dehydrogenase (LDH).
Phospho-fructokinase (PFK)
Lactic anaerobic s ys tem Summary
Glycogen
Pyruvate (Pyruvic Acid)
Anaerobic Glycolysis
ENERGY
Lactate Dehydrogenase (LDH)
Lactate (Lactic Acid)
P
ADENOSINE P P
ADENOSINE P P
P
THIS SYSTEM IS USED FOR ENERGY PRODUCTION IN HIGH INTENSITY EVENTS LASTING BETWEEN 10 SECS AND UP TO 3
MINUTES
CONCE
NTR
ATIO
N O
F ATP
TIME3 SECS 10 SECS 60 SECS 2 HRS
ATP STORE
ATP-PC SYSTEM LACTIC
ANAEROBIC SYSTEM
RATE OF ENERGYPRODUCTION
Advantages of the Lactic Anaerobic System
It is an anaerobic process, therefore it doesn’t have to wait for sufficient oxygen to be present.
This system releases energy quickly, so can supply ATP for high intensity short term exercise such as 400m runner and 100m swimmer.
It can be used for exercise between 10 seconds and 3 minutes, but peaks in events lasting approx 1 minute.
During aerobic activities such as 10,000 metres, this system can be called upon to produce an extra burst of energy during the race or at the end for a sprint finish.
Disdvantages of the Lactic Anaerobic System
This system builds up lactate (lactic acid), this can cause the enzymes that operate during glycolysis ie (PFK) to stop working properly, which inhibits energy production.
The intensity of exercise must be reduced or even stopped to allow the body to rid itself of lactate.
This system only releases approx 5% of the energy in a glycogen molecule as it is without oxygen.
The remaining 95% of energy in a glycogen molecule can only be released in the presence of oxygen …
… The Aerobic System
How can this system be improved?
Will increase stores of muscle glycogen
Will increase number of glycolytic enzymes (PFK)
Interval training
Fartlek training
Weight Training (65-85% of 1RM)
ATP-PC System.
Phosphocreatine is stored in the muscles.
PC is broken down by creatine kinase to produce energy.
Energy is used to resynthesise ATP.
ATP can then be broken down into ADP and a free phosphate to produce energy which can be used for muscular contractions.
This is an anaerobic system, no oxygen is involved.
