Energy Systems (Unit 5) Flashcards
Energy Continuum, Aerobic-ATP/PC and Anaerobic Glycolytic Systems, Lactate Accumulation, Lactate Threshold and OBLA, Oxygen Deficit and EPOC, Vo2 Max, Indirect Calorimetry-Lactate Sampling-Vo2 Max Test and Respiratory Exchange Ratio, Altitude Training, HIIT, Plyometrics and Speed Agility Quickness Test.
What are the 3 Energy Systems?
ATP/PC, Lactate Anaerobic, Aerobic Energy System
ATP (Adenosine Triphosphate) is the primary carrier of energy. The energy metabolised from food is formed here.
How is ATP Resynthesised?
When energy is required, ATP is broken down through hydrolysis. The high energy bond is broken and a phosphate is removed leaving adenosine diphosphate and an inorganic phosphate. ATP is constantly formed and broken down this is called resynthesis
What are the Characteristics of ATP?
-It has a limited store of 2-3 seconds
-Its an immediate usable source of energy
-Energy is required to re-synthesize and break down ATP
What Energy Systems Resynthesize ATP?
ATP/PC System (Phosphocreatine)
Anaerobic Glycolytic System (Lactic Acid)
Aerobic System (Glycogen)
What Makes up the Aerobic Energy System?
There are 3 stages with mini stages in-between. Stage 1 is Glycolysis, Stage 2 is the Kreb Cycle, Stage 3 is the Electron Transport Chain
What happens in Glycolysis?
There are 5 stages to Glycolysis, but oxygen needs to present.
- Glucose enters the cytoplasm
2.Glucose is phosphofructokinase (enzyme)
- The glucose 6-phosphate breaks down to form pyruvic acid
- 2 ATP is formed
- Acetyl- coenzyme A is formed and enters mitochondria and the Kreb cycle
What happens in the Kreb Cycle?
A series of cyclical chemical reactions that oxidise acetyl coenzyme A and citric acid
- It takes place in the mitochondria
- Acetyl coenzyme A combines with oxalaecitic acid to form citric acid
- This produces 2 ATP
- Co2 and H2O are produced (H+ ions produced)
- The H+ ion are transported to the Electron Transport Chain
What happens in the Electron Transport Chain?
- Hydrogen carried by FAD + NAD into the chain
- Happens in the cristae of the mitochondria
3.Hydrogen splits into electrons + ions
- Hydrogen ions are oxidized to form water + electrons to provide the energy to create 34 ATP
How do Carbohydrates Provide Energy?
Carbohydrates dissolve in the blood plasma and is transported around the body. It is used for the energy source resynthesis of ATP. Any excess glucose is stored in the muscles and liver as glycogen, once these stores are full excess glucose converts to fat droplets and stored in the adipose tissue
How do Fats Provide Energy?
Normally stored as triglycerides in adipose tissue, fatty acids may be converted to glucose when the diet is lacking in carbohydrates or when glycogen stores have been depleted
How does Beta Oxidation Create Energy?
(Breakdown of Fats)
The Kreb Cycle not only oxidizes carbohydrates, but also oxidizes fats when glycogen stores are depleted. Fatty acids formed from the breakdown of triglycerides are themselves broken down to Acetyl Coenzyme A which is used for resynthesis. Fat breakdown requires more oxygen than glucose due to having more carbon atoms therefore this breakdown can only occur at low intensity because so much O2 is required
What is the ATP/PC System?
This system can supply energy for high intensity activities for up to 10 seconds. The phosphocreatine (an energy rich-compound) can be found in the sarcoplasm of the muscles but there is only enough energy for 5-8 seconds
How is ATD converted to ATP?
Creatine kinase detects high levels of ADP and breaks the PC bond to transfer energy and convert ADP to ATP. Each molecule of PC broken down creates one molecule of ATP. So can only be replenished during low intensity work, with lots of oxygen available
What are the Advantages of ATP/PC?
-Immediate access to energy
-No fatiguing by-products
-ATP/PC stores resynthesized quickly (50% in 30s, 100% in 3mins)
-Creatine supplements extends ATP/PC system
-Delays onset of lactate anaerobic system
What are the Disadvantages of ATP/PC?
-Limited supply of ATP/PC
-One molecule of ATP produced for each PC module (inefficient)
-Only replenishes stores in O2 presence
What is the Lactate Anaerobic System?
The main provider of ATP for high intensity work for up to a peak of 1 minute but is taken over at 3 minutes. When Anaerobic glycolysis occurs to create ATP but O2 isn’t present the pyruvic acid is turned into lactic acid as a by-product. It kicks in after PC stores are depleted and involves the breakdown of glucose by the enzyme glycogen phosphorylase
What is the Enzyme used to Breakdown Glucose?
Phosphofructokinase activated by low PC levels, breaks down glucose into pyruvic acid. Lactate dehydrogenase (LDH) then breaks the pyruvic acid down into lactic acid due to the lack of O2
What are the Disadvantages of the Lactate Anaerobic System?
-Creates a lactic acid by-product
-Accumulation of lactic acid de-natures enzymes and prevents them increasing the rate of chemical reactions
-Only a small amount of energy can be released from glycogen under anaerobic conditions (5% as opposed to 95% aerobically)
What are the Advantages of the Lactate Anaerobic System?
-Can access energy quickly
-Can be resynthesized quickly due to few chemical reactions
-In the presence of oxygen, lactic acid can be converted back into glycogen or used as a fuel through oxidation into Co2 and O2 (Cori Cycle)
-Can be used for a sprint finish as extra energy burst
What is the Lactate Threshold?
As the body continues to work harder, more hydrogen is released as a result of glycolysis (pyruvic acid) and the Kreb Cycle. At a certain point, so much hydrogen enters the Electron Transport Chain that there is insufficient oxygen available to oxidise it. Excess hydrogen atoms cannot remain unattached so combine with pyruvate to form lactic acid
What is EPOC?
Excess Post-Exercise Oxygen Consumption-“the amount of oxygen consumed during recovery above which would have been consumed at rest during the same time.”
has 2 phases:
1)Fast component that replenishes O2 and PC levels
2)Slow component that removes lactic acid
What is Vo2 Max?
Usually referred to as Vo2 (the amount of oxygen we use to produce ATP). We consume more oxygen in relation to intensity increase to create more ATP (until maximal oxygen consumption is reached) which is 3-6 litres per minute. This is known as Vo2 max- “the maximum volume of oxygen that can be taken in and used by the muscles per minute”
