energy and the role of ATP Flashcards
energy is defined as
the capacity/ ability to perform work
ATP
adenosine triphosphate
- some stored
- use to manufacture hormones
- nerve conduction (e.g. reflex uses ATP
- gained from food intake
All energy for body functions comes from…
the breakdown of the chemical, ATP
high metabolism
use up ATP a lot quicker
e.g. interaction between muscles and bones keeps the body upright and under control
body needs energy sources that pemit muscles to work
e.g. effort needed by the abs and back muscles
3 energy systems can be categorised as:
aerobic and anaerobic
How is ATP used in our body?
need to split compound apart, to replenish, need to build it back tgt, repeat cycle
What actual is movement of muscles?
contraction and lengthening of muscles allows its movement (uses atp)
How much storage of ATP is there in the body and what happens after it is all used up?
2-3 seconds of ATP storage in body
then energy systems rebuild the ATP that is used up
have percentage of interaction between energy systems
Rebuild
Replenish, resynthesis
3 energy (replenish) systems
creatine phosphate system, lactic acid system. aerobic system(only one that requires o2, most efficient- others have limits)
periods of time don’t have o2 or have, therefore they occur at diff levels at diff time
how does the body get ATP to breakdown?
ATP chilling( potential energy)-> upon electrical nerve impulses from brain -> enzyme is released to ATP -> ATP split (last phosphate molecule breaks off, energy in the high energy bond is released-> becoming ADP+Pi+energy
where does energy locate in the ATP?
in the high energy phosphate bonds
use of ATP def
breakdown of high energy bonds to release energy for body functions
What impacts the substrate used in the re-generation of ADP to ATP and what substrates can there be?
Intensity and duration of exercise.
- phosphocreatine
- glucose, glycogen, lactic acid
- fat or protein
Which substances run the lactic system?
glucose and glycogen run the lactic system
which two states does the body create energy in?
at rest or during exercise
How does the body function to replenish ATP?
Energy input from energy systems to replenish ADP into ATP
Where is ATP stored?
Mostly in the muscles, amount can last for appx 2 seconds
Metabolic activities
a balancing act involving two kinds of activities that go on at the same time:
building up body tissues and energy stores (called anabolism)
breaking down body tissues and energy stores to get more fuel for body functions (called catabolism)
metabolism
chemical reactions in the body that changes food into energy (the 3 energy systems refilling adp into atp
Phosphorylation
the addition of a phosphoryl (PO3) group to a molecule (adp->atp
What do synthesise and resynthesise mean?
ATP is hydrolyzed into ADP and Pi, and then ADP and Pi combine to resynthesize ATP.
Why is it necessary for us to constantly resynthesise ATP?
Because we do not store a significant amount of ATP and need a continuous supply, it must be constantly resynthesized.
What is Creatine phosphate
The energy required to replenish ATP that ultimately comes from food
- molecule similar to ATP (in function) where it splits and releases energy
Where is creatine phosphate stored?
Muscle cells and brain cells.
What are the abbreviations for creatine phosphate?
CP, PC, PCr
How much CP is created by the body and how much is not?
appx half is synthesised by the body (in liver, kidneys, pancreas) and half comes from dietary intake of animal muscle (meat and fish)
- some take supplements
What are the fuels we take in from our diet that are used to make ATP?
Carbohydrates, fats, and proteins
What is the abbreviation for carbohydrates?
CHO
Carbohydrates include ____ and ____
sugars and starches
Describe the complexity of carbohydratez
may be simple or complex depending on the number of sugars in the molecule
What are some examples of simple carbohydrates and how many glucose molecules do they usually compose of?
composed of 1 or 2 glucose molecules
glucose, confectionary(sweets and chocolates), sugars in fruit, dairy and vegetables
e.g. of complex carbohydrates,how many glucose molecules do they usually consist of?
composed of many glucose molecules
starch, grains, bread, legumes, starchy vegetables (e..g potatoes)
Primary processing of carbohydrates
broken down by the digestive system into glucose for transportation in the blood to all cells, including muscle and liver cells
Which other place is glucose released from in the body? (that’s not stomach)
liver
released from liver into the blood to maintain blood glucose levels and allow for transportation of glucose to all cells in the body (including to muscle during exercise)
What are the 2 types of carbohydrates?
Simple and complex.
Where is glucose stored in the body?
Some in blood
Some stored as glycogen in muscles and liver
Where is glycogen used?
Used to power ATP production in both anaerobic (lactic acid system) and aerobic systems
What happens to excess glucose?
Converted to fat, which is stored in adipose (fat) tissue
Compare simple and complex carbs
complex-> lasts longer as energy source
GI value
Glycaemic index value
What does the GI value indicate?
How quickly blood glucose levels rise after consumption of a carbohydrate (how long it can be extracted from food and used
Do simple and complex carbs have high or low GI?
Simple carbs: high gi
Complex carbs: low GI
Should consume equal amount of simple and complex
What is the threshold for high GI and what are some examples of high GI foods?
79-100
glucose (GI=100), jellybeans, sports drinks, white rice, white bread, fruit juice
Benefits of high GI foods
instant energy
What is the threshold for low GI and what are some examples of low GI foods?
0-55
lentils, pasta, all bran cereal, apples, milk
Benefits of low GI foods
slow in digestion, slow sustained glucose release will provide energy for a long period of time
Fats
Lipids
What are fats made up of,describe actual structure
triglycerides and free fatty acids, made of a glycerol backbone with three fatty acid chains attached to it- the more complex the chain is, the worse it is for the body
triglyceride
type of lipid used for long term energy storage in the body
benefits of fats
extremely high in energy
sources of fats
oils, butter, nuts, fatty fish, dairy, avocado, pastry, junk food, fatty meat (e.g. salmon
where do excess carbs go
converted into fat for storage
how are fats transported
broken down and transported in blood as free fatty acids (FFAs)
triglycerides are stored in…
muscles and liver as adipose tissue
FFAs are stored in the…
blood
When will the body break down fat for energy?
used mainly during rest and periods of low intensity sub-maximal exercsie
Why does the body prefer to use carbohydrates as an energy source? Then why are fats still important?
Because it is more difficult to use the energy from fat during exercise. Important when the stores of carbs are depleted during prolonged, continual activity.
Proteins contain…
amino acids- building blocks of the body, essential and non-essential
Why are proteins needed for?
Growth and repair
When do proteins contribute to ATP production?
contribute very little to ATP production except in extreme circumstances like marathons or during starvation.
Sources of protein
meat, fish, poultry, eggs, dairy, beans, lentils, cereals, breads
Where can protein also be gained from (not dietary) in extreme circumstances?
breakdown body tissues, e.g. blood plasma, viscera, muscle
transportation of protein
amino acids are transported by the blood to the sites requiring them
Are proteins stored?
not stored.
they form part of tissues including muscles which can be broken down to release the amino acids.
How can amino acids in the blood be used?
fuel source for the aerobic system
How are excess amino acids processed?
converted to fat for storage in adipose tissue
‘hitting the wall’
during extended exercise, often marathon running or long-distance cycling, the athlete experiences sudden fatigue, a decrease in power output and the inability to improve power output
Happens when liver and muscle glycogen stores become exhausted
as a result, fat (rather than carbs) becomes the primary fuel source used by the aerobic system to produce ATP. (exhaustion of glycogen stores)
why does ‘hitting a wall’ occur?
when you’ve run low on glycogen (the storage form of glucose) and are relying predominately on fat for fuel
oxidation of fat is relatively slow compared to the oxidation of glycogen, thus slowed production of ATP
strategies to delay exhaustion of glycogen stores (hitting the wall)
carbohydrate loading/ consuming carbs during exercise to have a maintained supply of carbs
glycogen sparing
an adaptation to exercise includes an increased capacity of the aerobic system to metabolise fats.
means that trained individuals can rely less on glycogen, thereby sparing their glycogen stores.
process where glycogen stores are not used early in an exercise due to increased ability to use triglycerides to produce energy (use less therefore takes longer to exhaust
our body suaully creates energy in one of two states, when ____ or ______
rest or during exercise
What is Yield of ATP
amount of ADP that can be resynthesised into ATP
Rate of ATP
speed at which ADP can be resynthesised to ATP
At rest, carbohydrates contribute to appx ______ of food fuels required and fats _____. How does this change as the intensity and duration of exercise increase?
1/3 and 2/3
carbs increase contribution as exercise begins
at sub-maximal intensity (60-85% of max heart rate), carbs contribute 2/3 while fats contribute 1/3
Which factors determine the level of activity?
activity duration, activity intensity, level of aerobic fitness, amount and type of recovery available
disadvantages of anaerobic energy pathway
produce relatively small amounts of atp
only operate for short period
result in byproducts that are associated with muscle fatigue
Describe how long the atp-cp system lasts
used in explosive (short duration, high intensity)efforts to resynthesise atp
can be predominant for up to 10 sec and requires passive recovery (30- 180 sec) to replenish
where is cp stored
in muscles
in what activities is the atp-cp system predominant ?
weight lifting, spike in volleyball, athletic field events (shot put, high jump, javelin, long jump)
anaerobic glycolysis system:what is it, who uses it
muscles stores of glycogen are anaerobically broken down to release energy.
limited due to accumulation of metabolic by produces, some associated with muscular fatigue. e.g. lactate and hydrogen ions
track cyclists, swimmers, gymnasts in a floor routine
how much energy can be yield from the aerobic energy pathway?
38 moles from 1 mole of glucose
how does the aerobic energy pathway contribute to recovery?
provides muscle with oxygen that can help to replenish cp stores
remove and break down metabolic byproducts (lactic acid and hydrogen ions)
regulate body temp
chemical reaction of the aerobic energy system
glycogen-> glucose-> glycolysis; pyruvic acid–(o2)–> 38 mol energy, h20 co2 heat
the aerobic energy system is typically predominant in….
low to medium-intensity activities that last anywhere from two minutes to a few hours
e.g. middle and long distance running and swimming, road cycling
the way the energy systems work tgt is referred to as
interplay
the energy system that is considered ti be contributing most to atp synthesis is referred to as
predominant energy system
describe energy contribution (%) in increasing performance time(from gun firing to end)
as gun fires in sprint, all 3 systems are contributing
as intensity increase, atp cp system becomes preodminant, with the anaerobic glycolysis and aerobic energy systems contributing minimally.
as cp depletes, atp-cp system decrease while anaerobic glycolysis system increase, aerobic system will contribute minimally.
by the end, the anaerobic glycolysis will be predominant, atp-cp will be contributing minimally and the aerobic will be increasing.
Different names for the ATP-PC system
Phosphagen systen
ATP-CP system
What is another name for the lactic acid system?
Anaerobic glycolysis.
Lactic acid system is…
The incomplete breakdown of glucose, in a process of anaerobic glycolysis.
When does the lactic acid system provide the bulk of ATP production?
During high-intensity, sub-maximal efforts
What is an example of when lactic acid is mainly used?
400 metres run in athletics
performer is required to undertake repeated sprints that do not provide sufficient recovery time for the phosphagen system
high intensity, sub-maximal efforts
When does the lactic acid system take over the phosphagen?(specific time)
10-30 sec
How does the lactic acid system occur? (the process)
food fuel pathway occurs
Glycogen (stored carbohydrate) is used-> changed into a form of glucose and sent through glycolysis-> generate pyruvic acid OR( (AFTER GLYCOLYSIS)
spit out energy-> no o2-> excess pyruvic acid are turned into lactic acid and hydrogen ions OR continue to aerobic glycolysis in the mitochondria if there is o2
The energy released from the breakdown of glucose into pyruvic acid is the second way that ADP+Pi reforms in ATP
Food fuel pathway
CHO (simple and complex) eaten—–digestion—-> glucose (blood for transport)-> glycogen (stored in muscle and liver)/ some used instantly
Acidosis
Accumulation of lactic acid and hydrogen ions in the muscle cells and blood causing an increase in acidity, called acidosis.
- often felt as a burning sensation in our muscles
Lactate inflection point: what is it
the exercise intensity at which the blood concentration of lactate and/or lactic acid begins to increase rapidly
What is the result of acidosis?
reduces the cell’s ability to resynthesize ATP
resulting as the muscle fibres stop sliding across each other ceasing muscle action, i.e. contributor to fatigue
The fate of lactic acid
Lactic acid clearance
What happens when there is no accumulation of lactic acid? When does this occur?
During rest and exercise below the blood lactate threshold (LIP) (most times),
Rate of production equals the rate at which it is metabolised, so no accumulation
What determines the rate of lactic acid leaving the muscles and entering the blood stream?
the rate at which blood flows through the muscles.
What happens if LA is taken up by the heart and skeletal muscles?
LA may be taken up by the heart and other skeletal muscles
then converted back into pyruvic acid
and further metabolised to generate energy in the form of ATP
THEN THE FATE PART OCCURS
Fate of the lactic acid (where everything goes, precisely)
65% is oxidised to form co2 and h2o
20% is converted back into glucose by the liver. This is returned to the liver and muscles to be stored as glycogen
10% is converted in the liver to form protein
5% is converted into glucose.
How is Lactic acid removal conducted?
after completion of an exercise session, one can employ either an active or passive recovery mode.
When is active removal better than passive?
when LA accumulates during high intensity exercise
because of blood flow, therefore LA dispersal from the muscle is greater than during passive recovery
When is the rate at which LA is utilised as an energy source by the heart and skeletal muscles greater?
Greater during low intensity exercise than at rest.
When would pyruvic acid production exceed the required amount?
When energy demands are high,
Or when oxygen is not available,
more pyruvic acid is used produced than can be used by the aerobic system.
Discuss the process that carbohydrates go through when being consumed and then used as a food fuel. (3 marks)
eaten and enters the digestive system where it is broken down into glucose and absorbed into the blood for transport
then further broken down into glycogen and stored
It is then used as a food fuel for energy systems that require it
simple and complex carbohydrates have different absorption rates and digestion rates, when eaten, different rates of energy release occur.
Explain glycogen sparing and how is it advantageous for an endurance athlete. (2 marks)
some athletes train their body to rely more on fat storage rather than glycogen when in need of energy during exercise
this increases performance of athletes by increasing their endurance with a larger capacity of energy
usually the body predominantly relies on glycogen stores
sparing glycogen stores for long and later
therefore more glycogen is available for later in exercise
What sort of recovery should an athlete use to enhance lactic acid removal and what is the fate of the lactic acid? (2 marks)
active recovery
more blood flow thus better dispersal of lactic acid than passive recovery
65% –> co2
5% –> glucose
10%—> stored as protein
20%–> turned back into glucose then stored as glycogen in the liver
Most of a soccer match is completed at sub-maximal pace. When an athlete has to repeatedly sprint in the game, which energy system will provide energy for the athlete? What are two byproducts produced by this system? (2 marks)
lactic acid system= high intensity, sub-maximal effort
byproducts of lactic acid system: lactic acid, H+ ions
may switch to ATP-pc during sprints then increase % of lactic acid system as phosphagen depletes
State the duration, amount of atp produced, byproducts produced, and limitations of the ATP-PC system and the Lactic acid system. (4 marks)
ATP-PC:
short (10 sec of maximal effortt, normally 2-10 sec)
small amount of atp produced
no byproducts produced
limitations of having a small ATP yielf
Lactic acid:
2 minutes lasts, starts from 30 sec of activity to around 3 minutes
small amount of atp produced
lactic acid, h+ ions
limitations of muscle fatigue due to byproduct of lactic acid accumulating
Explain one of the processes of energy production that is utilised when oxygen is not available or an athlete’s energy demands are high. (3 marks)
the ATP-CP system operates similar to ATP splitting. An enzyme triggers the splitting of the compound in a creatine and phosphate molecule.
this breaking of high energy bond between the phosphocreatine releases energy
the energy and phosphate molecule is used to replenish adenosine triphosphate from the adenosine di-phosphate. PCr-> Pi+Cr ADP+Pi+E–>ATP
