All cells need energy to work, muscle cells need energy to contract and energy is derived from food. However, cells cannot get their energy directly from food. What chemical do cells get their energy from?
ATP - Adenosine TriPhosphate
What is the basic molecular composition of ATP?
1 Adenosine molecule and 3 Phosphate molecules.
In order to produce energy ATP must be broken down.
1) What are the results of this process?
2) Where does the energy come from?
1) ATP -> ADP (Adenosine DiPhosphate) + energy for biological work + Phosphate.
2) From the high energy bond between the phosphates.
ATP is very unstable and so cannot be stored in large quantities. We can only store enough to last a should period of time. Approximately how long?
2 - 3 seconds
For the muscles to continue contracting what must happen when the store of ATP is used up?
The supply must of ATP must be rebuilt.
The supply of ATP can be rebuilt in 3 ways. What are they?
1) ATP-CP System (anaerobic)2) Lactate System (anaerobic)
3) Aerobic System
What is ATP-CP System also known as?
What happens during the first part of the ATP-CP System?
The first part of this system uses up the small reserves of ATP stored in the muscle cells.
Approximately how long does the stored ATP last for?
What happens during the second part of the ATP-CP System?
During the second part of this system ATP is rebuilt using the energy released by breaking down CP, which is also stored in the muscles.
What are the positives of the ATP-CP System?
1) Intensity with ATP - maximal (100%)
2) Intensity with CP - very high (95-100%)
3) No waste products
What are the negatives of the ATP-CP System?
1) Reserves run out very quickly
What is the approximate recovery time of the ATP-CP System?
Approximately 2 mins
Approximately how long does the ATP created using CP last for?
Approx 9-10 seconds (<10) more after the store of ATP runs out.
What is the Lactate System also known as?
What does the Lactate System use as an energy source to help rebuild ATP?
1) Glycogen stored in muscle cells (closest to the site needed so used first)
2) Glycogen stored in the liver
3) Glucose in the bloodstream
What is the main con associated with the Lactate System?
Incomplete breakdown of glucose leads to a build up of waste product;
1) Lactic Acid
2) Hydrogen Ions
These cause extreme discomfort and force a lowering of the intensity level.
What intensity levels are reached with the Lactate System?
Approx (60) 75-95% of your maximum effort.
How long does the Lactate System last as the main provider of energy?
Approx 90 seconds
What is the approximate recovery time of the Lactate System?
20 mins -> 2 hours
Within the Aerobic System what does the arrival of O2 allow for?
It allows for the complete breakdown of lactic acid and hydrogen ions (H+).
What is the main con associated with the Aerobic System?
Intensity levels are reduced to approx 60% of your max.
What fuels are used within the Aerobic System?
1) Glycogen / Glucose
2) Fats (triglycerides stored in the muscles and fatty acids stored as body fats)
Approximately how long can the Aerobic System last as the main provider of energy?
1) Carb supply can last up to approx 2 hours.
2) Then the main fuel source is switched to fats. When this happens the intensity is forced lower and discomfort is experienced for a time - "Hitting the Wall".
3) Fats as a fuel source can last for days but the intensity is lower than before (<60%).
What is DOMS?
Delayed Onset Muscle Soreness
What is DOMS caused by?
DOMS is caused by micro trauma to muscle fibres e.g. tiny tears and damage.
Do the various energy systems work independently of each other e.g. one system runs out before the next one kicks in?
No. At any time you may be using a mixture of some or all of the systems at once.
What are the waste products of the three energy systems?
ATP-CP = None
Lactate = Lactic Acid[and Hydrogen Ions (H+)]
Aerobic Glycolysis (aerobic with glycogen/glucose) = CO2 + O2 (and heat)
Fat Acid Oxidation (aerobic with fats) = CO2 + O2 (and heat)
List 6 characteristics of the anaerobic system.
1. Mainly occurs without oxygen.
2. High intensity (above 80% MHR).
3. Short duration.
4. Fatigue quickly.
5. May have waste products (Lactic Acid [and Hydrogen Ions (H+)])
6. Fast twitch muscle fibres.
List 6 characteristics of the aerobic system.
1. Occurs with oxygen.
2. Low to medium intensity (up to approx. 80% MHR.
3. Longer duration.
4. Fatigue more slowly.
5. Waste products [CO2 + O2 (and heat)].
6. Slow twitch fibres.
What is EPOC?
Excess Post-Exercise Oxygen Consumption
What is the excess oxygen used for?
1. Replace energy stores.
2. Break down lactic acid and other waste.
3. Repair and build.
4. Maintain elevated BMR.
5. Replenish ATP+CP stores etc.
What does the EPOC lead to?
Higher energy usage (burning of calories)
What can increase your level of EPOC?
1. Higher intensity workout.
2. Resistance training.
3. Interval / Anaerobic training.
*you would need to increase duration of aerobic training to increase EPOC
During what type of exercise is a higher percentage of fat burned?
*but lower overall calories burned.
What is the benefit of high intensity exercise in relation to fat burning?
A lower percentage of fat may be burned but higher amount of overall calories burned.
High intensity exercise also increases the EPOC.
What does VO2 stand for?
Volume of O2Maximum uptake - (ability to use oxygen)
What are the benefits of an increased VO2 Max?
Increased VO2 Max means that a person will be able to exercise at a higher intensity and for longer before going into anaerobic energy systems and fatigue.
What is Aerobic Capacity and why is it important to train?
It is the ability to maintain a high work output for a long period of time.
It is important to train as individuals with high endurance are more resistant to fatigue and will have a faster recovery.
What is anaerobic capacity and why is it important to train?
It is the ability to perform very high workloads repeatedly.
It is important to train as it plays an important role in improving tolerance to lactic acid build up and therefore the ability to cope with the stop-start nature of many sports.
List three examples of training to develop the ATP-CP Energy System.
1) 10 reps of 30 metres with 30 seconds rest x 3 sets with 3 minutes rest between sets.
2) 15 x 60 metres with 60 seconds recovery
3) 20 x 20 metre shuttle runs with 45 second recovery.
List two examples of training to develop the Lactate System (Anaerobic Glycolytic).
1) 8 reps x 300 metres fast with 45 seconds recovery - until pace significantly slows x 5 sets.
2) 150 metre intervals at 400 metre pace - 20 seconds recovery - until pace significantly slows.