6. Energy Systems And Their Relation To Exercise Flashcards
What are the three main energy systems?
- Creatine phosphate
- Lactic
- Aerobic
What energy-rich compound can be identified as our main currency?
Adenosine triphosphate.
Describe how energy is released from ATP?
ATP release its energy when one of its two high energy bonds is broken (by the enzyme ATPase).
What is the main energy system employed in sprinting?
Creatine phosphate.
Which energy system require no oxygen?
Creatine phosphate.
How are creatine phosphate stores replenished?
The body replenishes its supply of creatine phosphate from one of two sources – the liver and kidneys from amino acids or dietary creatine, primarily from meat and fish.
Approximately how long does it take the body to replenish creatine phosphate stores?
ATP stores are 50% restored after 30 seconds and fully restored after about 5 minutes rest.
For who long can the lactate system sustain activity?
The lactate system can supply the energy for higher intensity exercise activity for between 60 and 180 seconds.
Give an example of an athletic event that would rely on lactate system.
400 metre race.
Which energy system is dominate during lower-intensity activities?
Aerobic.
Which energy system results in the incomplete breakdown of carbohydrate?
Lactic.
The use of which energy system can result in the characteristics ‘burning’ sensation in muscles?
Lactic.
Which energy system involves the complete breakdown of carbohydrate and fats?
Aerobic.
What are the by-products of the aerobic energy system?
The aerobic system produces carbon dioxide, water and heat as by-products of the breakdown of CHO and fat.
Give three examples of training adaptations through aerobic training.
- Pulmonary - improved efficiency of the respiratory muscles.
- Cardiovascular – significant hypertrophy and improved coronary blood flow.
- Muscular – a greater ability
What are the main training adaptations targeted at the CP system?
To increase muscle size (fast twitch fibres) and improve activation of the muscle by the nervous system.
What is lactate tolerance and how is it improved?
Lactate tolerance is the body’s ability to withstand the build-up of lactic acid which can be improved by regular anaerobic training.
Energy currency
- Energy is required for movement, heat generation and tissue growth and repair.
- In the body, energy exists in the form of Adenosine Triphosphate (ATP).
- Carbohydrates, proteins and fats are all sources of energy.
- ATP supply must meet the demands of exercise in order for it to continue.
Structure of ATP
- ATP is made up of one adenosine molecule and three phosphate ones.
- Energy is stored in the bonds that link the phosphate molecules to the adenosine.
- The bonds are broken down by the enzyme ATPase to release energy.
- Muscle ATP stores are limited, so they must be continually replenished by the creatine phosphate, lactate and aerobic energy systems.
Creatine phosphate system – immediate energy
- Energy for muscular contraction is required quickly for high-intensity, low duration activities.
- The energy is supplied by intramuscular (inside the muscle) stores of ATP and creatine phosphate.
- ATP and creatine phosphate stores only last for a few seconds – such high intensities can’t be sustained for much longer than this.
- This system is derived exclusively from chemical energy stored in the muscles and requires no oxygen (i.e. it’s anaerobic).
Lactate system
- Lactate system bridges the gap between the aerobic and creatine phosphate systems.
- Allows rapid ATP production to continue beyond the first few seconds of the creatine phosphate system.
- Can sustain exercise activity for 60-180 seconds.
- Waste products of this process can bring about a decline in performance with recovery times ranging from 20 minutes to two hours.
Aerobic system
- The aerobic energy system produces ATP from the complete breakdown of carbohydrate and fat, in the presence of oxygen.
- Its by-products are carbon dioxide, water and heat.
- No limits on the amounts of ATP that can be produced but the rate of ATP production is limited.
- Recovery time will be the time taken to eat, drink and replenish fuel stores.
Lactate training adaptations
- Lactate training adaptations are related to improvements in the cardiorespiratory system.
- Muscles that utilise more oxygen will produce less lactic acid at a given exercise intensity.
- Regular anaerobic training improves tolerance to waste products.
Creatine phosphate training adaptations
- High-intensity activities have a significant training effect.
- They can result in increased muscle mass and a predominance of fast twitch muscle fibres.
- They may also increase muscular stores of anaerobic fuel sources.
Interaction of energy systems
- There is considerable overlap between the three energy systems.
- All three systems could potentially provide the body with energy simultaneously.
- As the demands of the activity change, so do the relative contributions of the energy systems.
