1 Energy Systems v2 Flashcards
What is the primary energy provider in the body during exercise?
Adenosine triphosphate (ATP)
ATP is the only usable form of chemical energy in the body.
What are the three energy systems used to re-synthesize ATP?
- Aerobic system
- ATP-PC system
- Anaerobic glycolytic system
In which condition is the aerobic system preferred for energy production?
When exercise intensity is low and oxygen supply is high, e.g. jogging.
What is glycolysis?
A process in which glucose is converted to pyruvate to produce energy.
What is the maximum amount of ATP produced by the complete oxidation of glucose in the aerobic system?
Up to 38 molecules of ATP.
During which type of exercise are the anaerobic glycolytic and ATP-PC systems primarily used?
Short duration/high intensity exercise.
Krebs Cycle
the two acetyl groups combine with oxaloacetic acid to form citric acid.
hydrogen is removed from the citric acid and the now rearranged form of citric acid undergoes oxidative carboxylation
the carbon forms carbon dioxide which is transported to the lungs and breathed out
the hydrogen is transported to the electron transport chain
the result of these reactions result in the production of 2 ATP molecules
What does the electron transport chain produce?
34 molecules of ATP.
What is the role of phosphocreatine (PC) in ATP production?
It is an energy-rich phosphate compound used to resynthesize ATP.
Fill in the blank: The aerobic system consists of three stages: Glycolysis, ________, and Electron Transport Chain.
Krebs cycle
True or False: The aerobic system produces fatiguing by-products.
False.
What are the advantages of the aerobic system?
- More ATP can be produced: 36 ATP
- No fatiguing by-products
- Lots of glycogen and triglyceride stores
What is the disadvantage of the aerobic system?
It takes a while for enough oxygen to become available to meet the demands of the activity.
What is beta oxidation?
The process by which stored fat is broken down into glycerol and free fatty acids for energy production.
What is VO2 max?
The maximum amount of oxygen that an individual can utilise during intense exercise.
What factors affect VO2 max?
- Genetics
- Age
- Training status
Identify one method used to measure energy expenditure.
- Indirect calorimetry
- Lactate sampling
- Respiratory exchange ratio
What happens during oxygen deficit?
The body uses anaerobic pathways to produce ATP until sufficient oxygen is available.
What is the role of enzymes in ATP breakdown?
Enzymes like ATPase are used to break down ATP into ADP and inorganic phosphate.
What is the significance of the lactate threshold?
It indicates the exercise intensity at which lactate starts to accumulate in the blood.
What is the importance of goal setting in sports psychology?
It enhances motivation and performance by providing direction and measurable targets.
What is the main energy system used during high-intensity, short-duration activity lasting between 5 and 8 seconds?
ATP-PC system
The ATP-PC system relies on phosphocreatine for rapid ATP re-synthesis.
How long can the ATP-PC system provide energy?
8 seconds
Can last up to 10 with creatine supplementation
What is the primary disadvantage of the ATP-PC system?
Limited phosphocreatine supply
The stores can only last for approximately 8 seconds.
Which enzyme activates the breakdown of glycogen into glucose during anaerobic glycolysis?
Glycogen phosphorylase
This process occurs when the ATP-PC stores are low.
What is produced from pyruvic acid during anaerobic glycolysis?
Lactic acid
This transformation occurs in the absence of oxygen.
What is the net result of glycolysis for one molecule of glucose?
2 ATP
Although four ATP are produced, two are used in the glycolysis process itself.
What type of exercise predominantly uses the anaerobic glycolytic system?
High-intensity activities lasting up to 3 minutes
This includes events like the 400 m sprint.
What is the main by-product of the anaerobic glycolytic system?
Lactic acid
The accumulation of lactic acid can lead to muscle fatigue.
What is the maximum volume of oxygen that can be taken up by the muscles per minute called?
VO2 max
It indicates an individual’s aerobic capacity.
What is the term for when there is not enough oxygen available at the start of exercise?
Sub-maximal oxygen deficit
This occurs as the body adjusts to increased energy demands.
What is the difference between maximal and sub-maximal oxygen deficit?
Maximal oxygen deficit indicates greater anaerobic effort due to insufficient oxygen during high-intensity exercise
This leads to more reliance on anaerobic systems.
What is the primary advantage of the anaerobic glycolytic system?
ATP can be re-synthesised quickly
This system can produce energy for longer than the ATP-PC system.
What type of muscle fibers are primarily involved in aerobic pathways?
Slow twitch fibers (Type 1)
These fibers are more endurance-based and less likely to fatigue.
What is the primary pathway for ATP production in fast twitch fibers?
Lactate anaerobic energy system
Fast twitch fibers are recruited for high-intensity activities.
Fill in the blank: The energy continuum describes the type of respiration used by physical activities, which can be either _______ or _______.
aerobic, anaerobic
The type of respiration depends on the intensity and duration of exercise.
What happens to lactic acid in the presence of oxygen?
It can be converted back into liver glycogen or used as fuel
This process occurs during recovery periods.
During which type of activity is the aerobic system predominantly used?
Long duration, lower intensity activities
Examples include marathons and cross-country skiing.
What is EPOC?
Excess post-exercise oxygen consumption
It refers to the elevated oxygen intake after exercise to aid recovery.
What is the maximum amount of ATP produced by slow twitch fibers from one glucose molecule?
Up to 36 ATP
Slow twitch fibers utilize aerobic respiration efficiently.
What is EPOC?
The amount of oxygen consumed during recovery above that which would have been consumed at rest during the same time.
EPOC stands for excess post-exercise oxygen consumption.
What are the two main components of EPOC?
- Fast component
- Slow component
What occurs during the fast component of EPOC?
Restoration of ATP and phosphocreatine stores and the re-saturation of myoglobin with oxygen.
How long does complete restoration of phosphocreatine take?
Up to 3 minutes.
How much oxygen is consumed during the fast replenishment stage?
Approximately 3 litres.
What is the slow component of EPOC also referred to as?
The lactacid component.
What are the functions of the slow replenishment stage?
- Removal of lactic acid
- Restoration of myoglobin oxygen stores
How can lactic acid be removed during recovery?
- Converted back to pyruvate
- Transported to the liver via the Cori cycle
- Converted into protein
- Removed in sweat and urine
What is the Cori cycle?
The process where lactic acid is transported in the blood to the liver where it is converted to blood glucose and glycogen.
What is the relationship between body temperature and recovery?
When temperature remains high, respiratory rates remain high, helping take in more oxygen during recovery.
What is a nutritional window for optimal recovery after exercise?
- First window: 30 minutes post-exercise (3:1 or 4:1 carbohydrate to protein ratio)
- Second window: 1-3 hours post-exercise (high in protein, carbohydrate, and healthy fat)
What is lactate accumulation?
The buildup of lactate in the muscles due to anaerobic glycolysis during high-intensity exercise.
What is the lactate threshold?
The point during exercise at which lactic acid quickly accumulates in the blood.
What is OBLA?
Onset blood lactate accumulation, usually when lactate levels reach around 4mmol per litre.
How does fitness level affect lactate threshold?
As fitness increases, the lactate threshold is delayed, allowing higher intensity exercise before lactate accumulation.
Fill in the blank: The higher the exercise intensity, the greater the demand for _______.
[ATP]
True or False: Lactic acid and lactate are the same thing.
False.
What adaptations occur in trained muscles to delay OBLA?
- Increased numbers of mitochondria
- Increased myoglobin
- Increased capillary density
What happens to lactate levels during intense exercise?
Lactate levels rise dramatically as exercise intensity increases.
What is the role of slow twitch fibres in lactate production?
Slow twitch fibres produce less lactate than fast twitch fibres due to more effective glycogen breakdown in the presence of oxygen.
What can help accelerate the removal of lactic acid?
Performing a cool-down.
What is the effect of high body temperature on recovery?
It requires extra oxygen to fuel the increased respiratory rate until normal temperature is restored.
What is OBLA?
Onset of Blood Lactate Accumulation.
How does regular training affect OBLA?
It helps delay OBLA due to adaptations in trained muscles.
What physiological adaptations occur in trained muscles?
- Increased numbers of mitochondria
- Increased myoglobin
- Increased capillary density.
Why do elite sprinters have better anaerobic endurance?
Their bodies adapt to cope with higher levels of lactate.
What is the buffering process in relation to lactate?
It increases the rate of lactate removal, allowing athletes to work at higher intensities longer.
What is VO2 max?
The maximum volume of oxygen that can be taken up and used by the muscles per minute.
What is the average VO2 max for an A-level male student?
45-55 ml/kg/min.
What physiological factors can increase VO2 max?
- Increased maximum cardiac output
- Increased stroke volume
- Increased levels of hemoglobin.
What lifestyle factors can reduce VO2 max?
- Smoking
- Sedentary lifestyle
- Poor diet.
How does body composition affect VO2 max?
A higher percentage of body fat decreases VO2 max.
What is calorimetry?
The calculation of heat in physical changes and chemical reactions.
What is indirect calorimetry?
It measures the production of CO2 and/or the consumption of O2.
What do blood lactate measurements indicate?
They monitor training and predict performance.
What is the respiratory exchange ratio (RER)?
The ratio of carbon dioxide produced compared to oxygen consumed.
What training method is used to improve anaerobic capacity?
Plyometrics.
What is altitude training?
Training usually done at 2500 m+ above sea level where the partial pressure of oxygen is lower.
What is the impact of altitude training on aerobic performance?
It may initially reduce aerobic performance due to lower oxygen availability.
What is high intensity interval training (HIIT)?
Training involving short intervals of maximum intensity exercise followed by recovery intervals.
What does SAQ training aim to improve?
Multi-directional movement through developing the neuromuscular system.
What does a higher RER value indicate?
The performer is using carbohydrates and is likely in anaerobic respiration.
What is the effect of age on VO2 max?
VO2 max declines as we get older.
What is SAQ training?
SAQ training refers to Speed, Agility, and Quickness training, which involves sport-specific drills performed with maximum force at high speed
SAQ training is designed to enhance athletic performance.
How is energy provided during SAQ training?
Energy is provided anaerobically
Anaerobic energy production occurs without oxygen and is crucial for high-intensity activities.
What is EPOC?
EPOC stands for Excess Post-exercise Oxygen Consumption
EPOC refers to the increased rate of oxygen intake following strenuous activity.
What is the importance of oxygen consumption during exercise?
Oxygen consumption is important for energy production during exercise and recovery
It reflects how hard an athlete is working and aids in recovery processes.
What information do measurements of energy expenditure provide to athletes?
Measurements of energy expenditure provide information on how hard athletes are working and which energy system is producing energy
This helps athletes optimize their training.
Define lactate sampling.
Lactate sampling is a method used to measure the concentration of lactate in the blood to assess training effectiveness
It helps athletes monitor their performance and recovery.
Explain how the majority of energy was provided during Wayde Van Niekerk’s 400 m race.
The majority of energy was provided anaerobically, primarily through the glycolytic system
The 400 m race is a high-intensity event requiring quick energy production.
What are the functions of the fast component of EPOC?
The fast component of EPOC includes replenishing ATP and creatine phosphate stores and restoring oxygen levels in the muscles
These functions are achieved through increased breathing and heart rate.
What factors can affect lactate threshold?
Factors that can affect lactate threshold include training status, exercise intensity, and muscle fiber composition
A higher lactate threshold allows for better performance.
Why might marathon runners choose to train at altitude?
Marathon runners may train at altitude to improve their aerobic capacity and enhance oxygen delivery to muscles
Training at altitude can lead to adaptations that improve performance at sea level.
What are potential problems associated with altitude training?
Potential problems include altitude sickness, decreased training intensity, and longer recovery times
These can negatively impact performance if not managed properly.
What is the main energy system used in a triathlon?
The main energy system used throughout a triathlon is the oxidative system
This system supports prolonged, lower-intensity exercise like swimming, cycling, and running.
Why does a triathlete continue to breathe heavily after finishing the race?
Breathlessness occurs due to the body’s need to repay the oxygen debt accumulated during exercise
This helps restore normal physiological functions post-exercise.
What are the two aspects of skill in sports?
The two aspects of skill are cognitive (thinking) and motor (moving)
Both aspects are essential for effective performance in sports.
What is information processing in sports?
Information processing is the process by which sports performers collect information from the environment, interpret it, and act upon it
This involves decision-making prior to executing skills.
What senses do sports performers use to collect information?
Sports performers use hearing, vision, touch, balance, and kinesthesis to collect information
These senses help athletes make informed decisions during performance.
What influences decision-making in sports?
Decision-making is influenced by the information collected by the senses and cognitive processes
Factors include previous experiences and situational context.
What is Hick’s law?
Hick’s law states that the time it takes to make a decision increases with the number of choices available
This principle highlights the impact of complexity on decision-making speed.
What is the psychological refractory period?
The psychological refractory period is the delay in response to a second stimulus when a first stimulus has already been processed
This phenomenon affects reaction times in sports.
What is the single channel hypothesis?
The single channel hypothesis suggests that only one piece of information can be processed at a time
This implies limitations in a performer’s ability to react to multiple stimuli simultaneously.
What is a schema in sports performance?
A schema is a mental framework that helps athletes control movement and adapt information based on past experiences
It allows for faster and more effective responses during performance.
what is the electron transport chain
the hydrogen from the krebs cycle is carried to the electron transport chain by hydrogen carriers
the hydrogen splits into hydrogen and electrons and they are charged with potential energy
the hydrogen ions are oxidised to form water while the hydrogen electrons provide the energy to re-synthesise ATP
throughout this process 34 ATP are formed
