chapter 6 Flashcards
Adenosine Triphosphate (ATP): The Body’s Energy Currency
definition:
- ATP provides energy for muscle contractions.
- An ATP molecule consists of adenosine and a chain of three inorganic phosphate molecules bound together by high-energy chemical bonds.
- The energy that powers muscle contractions is obtained from the breakdown of ATP.
Adenosine Triphosphate (ATP): The Body’s Energy Currency
by-products:
-The breakdown of an ATP molecule produces the following by-products: Adenosine Diphosphate (ADP) and an inorganic phosphate molecule (Pi).
Adenosine Triphosphate (ATP): The Body’s Energy Currency
capacity:
- Limited stores of intramuscular ATP within the body.
- There is enough to power 1-2 seconds of maximal intensity exercise.
Adenosine Triphosphate (ATP): The Body’s Energy Currency
resynthesis of ATP:
-Once intramuscular ATP stores begin to deplete, chemical reactions within the muscle start to replenish ATP stores (connect ADP + Pi to create ATP), allowing the muscles to sustain muscle contractions.
Adenosine Triphosphate (ATP): The Body’s Energy Currency
energy systems:
The energy required for ATP resynthesis is obtained from the breakdown of creatine phosphate (phosphocreatine), glycogen (carbohydrates), triglycerides (fats) and proteins.
Energy Fuels – Converting Food To Energy
Creatine Phosphate
definition:
energy system:
Definition:
-Creatine phosphate (CP) is a chemical compound found in muscle cells that is capable of storing and releasing energy that can be used to resynthesise ATP from ADP and Pi.
Energy System:
-Creatine phosphate fuels that ATP-CP energy system as it can be rapidly broken down without relying on the presence of oxygen.
Energy Fuels – Converting Food To Energy
Creatine Phosphate
capacity:
recovery:
Capacity:
- The muscles have limited stores of creatine phosphate. There is only enough creatine phosphate to fuel 10 seconds of maximal intensity activity.
Recovery:
- Undertaking a passive recovery (rest or standing still) allows the athlete to replenish creatine phosphate stores. 70% of creatine phosphate stores are replenished in 30 seconds; 98% of creatine phosphate stores are replenished in 3 minutes.
Energy Fuels – Converting Food To Energy
carbohydrates
definition:
food sources:
Definition:
- Carbohydrates are naturally occurring compounds that consist of carbon, hydrogen and oxygen.
Food Sources:
-Carbohydrates are found in breads, cereals, rice, pasta and most fruits and vegetables.
-Foods with a high glycaemic index that are rapidly digested and absorbed and result in a rapid-rise in blood glucose levels include sugar, potatoes, watermelon, many breakfast cereals and white rice.
-Foods with a low glycaemic index that are slowly broken down and result in gradual rises in blood-glucose levels include most fruits and vegetables, grainy breads, pasta, lentils, milk and yoghurt.
Energy Fuels – Converting Food To Energy
carbohydrates
in the body:
energy systems:
dietary intake:
In the body:
- Carbohydrates are transported through the bloodstream in the form of glucose and are stored in the muscle and liver as glycogen.
- carbohydrates are stored at various sites around the body as adipose tissue.
Energy Systems:
-Carbohydrates provide the energy for ATP resynthesis for the anaerobic glycolysis energy system (no oxygen required) and aerobic energy system (oxygen required) and are the body’s preferred fuel source during exercise.
Dietary Intake:
- Carbohydrates should make up 55-65% of an individual’s total daily intake.
Energy Fuels – Converting Food To Energy
fats
definition:
food sources:
dietary intake:
Definition:
Fats are an essential component of a balanced diet.
Food Sources:
- Both saturated and unsaturated fats are found in many different foods.
- Saturated fats are found in animal foods such as dairy products (milk, chees) and meat products whereas unsaturated fats are found in vegetable oils, tuna, olive oil, avocados and nuts.
Dietary Intake:
It is recommended that fats make up about 20-25% of the average daily energy intake.
Energy Fuels – Converting Food To Energy
fats
in the body:
energy systems:
In the body:
- Fats are broken down and travel through the bloodstream as free fatty acids (FFAs).
- They are stored intramuscularly (in the muscle) as triglycerides.
- Excess fat is stored as adipose tissue at various sites around the body.
Energy Systems:
-Fats are primarily as an energy source at rest and during low intensity exercise.
- Fats are more difficult to breakdown than carbohydrates and they require more greater amounts of oxygen to do so.
- As their rate of ATP resynthesis is slow, fats are not a preferred fuel source during exercise.
- They are only used as a fuel source during prolonged submaximal exercise by the aerobic energy system, when glycogen stores are depleted (usually after 90-120 minutes of continuous exercise).
Energy Fuels – Converting Food To Energy
protein
definition:
food sources:
in the body:
Definition:
- Protein is an essential component of a balanced diet.
- Protein allows for muscle growth and repair, fights disease, helps chemical reactions (enzymes), production of red blood cells and hormones and transports material around the body.
Food Sources:
Protein-rich foods include meat, poultry, eggs and dairy products.
In the body:
Proteins travel through the bloodstream as amino acids and are stored in the body as muscle tissue.
Energy Fuels – Converting Food To Energy
protein
energy systems;
dietary intake:
Energy Systems:
- Due to the complex chemical reactions required to break down protein, they are not a preferred fuel source.
- Proteins are only used in extreme circumstances as a fuel source (during starvation or ultra-endurance events) when the body has severely depleted its carbohydrate and fats stores.
Dietary Intake:
- It is recommended that proteins make up about 15% of the average daily intake.
Energy Systems and Pathways
At the commencement of exercise, all three energy systems contribute to the resynthesis of ATP.
The energy system that is the predominant supplier of energy for ATP resynthesis is dependent on:
- Exercise Duration – how long the activity lasts for. (Determines the yield of ATP required).
- Exercise Intensity - how hard the exercise is performed. (Determines the rate of ATP synthesis)
Generally, as exercise duration increases, the intensity at which it can be performed decreases.
Comparing and Contrasting the Anaerobic and Aerobic Pathways
SIMILARITIES:
- Both pathways are responsible for ATP resynthesis.
- Both pathways use glycogen to provide the energy for the resynthesis of ATP.
- Both pathways produce by-products.
DIFFERENCES:
- The aerobic system produces ATP in the presence of oxygen and the anaerobic systems produce ATP without oxygen.
- In the aerobic energy system, glycogen can be completely broken down and the by-products carbon dioxide, water and ATP are produced, whereas in the anaerobic systems glycogen is not completely broken down and the by-products of lactate and hydrogen ions are produced.
- The aerobic pathway produces ATP at a much slower rate than the anaerobic pathways, which produce ATP at a much faster rate.
- The aerobic pathways produces a greater yield than the anaerobic pathways.
ATP demand:
Refers to how much ATP is required during an activity and therefore needs to be resynthesised.
Rate:
Refers to how quickly ATP is resynthesised. For example, The ATP-CP system resynthesises ATP at the fastest rate and therefore this energy system is predominant during maximal intensity activities whereas the Aerobic Energy System resynthesises ATP at the slowest fat.
Yield:
Refers to the total amount of ATP produced. For example, The ATP-CP system can only produce 0.7 moles of ATP from 1 mole of creatine phosphate whereas the Aerobic Energy System can produce 38 moles of ATP from 1 mole of glucose.
Characteristics of the Three Energy Systems
- The three energy systems work together via the process of interplay to supply energy for the resynthesis of ATP.
- The energy system continuum shows how the energy systems interact to provide energy for the resynthesis of ATP.
- It highlights the predominance of the three energy systems according to the duration and intensity of the activity.
The ATP-CP System
alternative names:
anaerobic or aerobic:
fuel source:
Alternative Names:
Phosphagen System, ATP-PC system, Creatine Phosphate system
Anaerobic or Aerobic:
The ATP-CP system does not rely on the presence of oxygen.
Fuel Source:
Creatine phosphate (also known as phosphocreatine) – stored in small quantities in muscle cells.
The ATP-CP System
intensity:
duration:
rate of ATP production:
Intensity:
-High, 95%+ maximum Heart Rate
Duration:
-0-10 seconds.
-The ATP-CP system is the predominant energy supplier within the first 6 seconds of high-intensity exercise, but its capacity is depleted after 6-10 seconds of maximal intensity exercise.
Rate of ATP production:
- Fastest rate.
- This is because this energy system is the least complicated of the three energy systems (fewer chemical reactions) and because creatine phosphate is found in the muscle cells.
The ATP-CP System
yield of ATP:
causes of fatigue:
type of recovery:
Yield of ATP:
- 0.7 – 1.0 mole of ATP per creatine phosphate mole.
Causes of Fatigue:
- Depletion of creatine phosphate stores.
Type of Recovery:
- Passive recovery (resting or standing still) allows for creatine phosphate stores to be fully replenished within 3 minutes of completing the activity.
The ATP-CP System
metabolic by-products:
sporting events:
fitness components that rely on the atp-cp system:
Metabolic By-Products:
- Inorganic phosphates (Pi) and ADP (adenosine diphosphate)
Sporting Events that utilise the ATP-CP System: - Athletic field events (High Jump, Shot Put), Short sprints 50-100m in length, Tennis Serve, Gymnastic Vault, Golf Drive.
Fitness Components that rely on the ATP-CP System:
- Muscular strength, muscular power, anaerobic power, speed and agility, reaction time.
The Anaerobic Glycolysis Energy System
alternative names:
anaerobic or aerobic:
fuel source:
Alternative Names:
- Lactic Acid System
Anaerobic or Aerobic:
- The Anaerobic Glycolysis Energy System does not rely on the presence of oxygen
Fuel Source:
- Glycogen
