Energy systems Flashcards
What are the 3 components of the energy continuim?
-Phosphocreatine production
-glycolytic system
-The aerobic system
-are all active simultaneously
What is the glycolytic system
-system for breaking down sugar in anaerobic conditions. Starts at 0, then peaks at around 20 seconds, then decreases rapidly and finished at around 50 seconds. -Produces large amount of energy at start then decreases-short supply
what is the aerobic system?
uses oxygen- starts at 0, has slow and low energy production but is able to keep generating energy over a long period of time -used for endurance sports
Describe the bonds within ATP ?
-has high energy bond between adenine and phosphate group-requires a lot of energy to make and break
What is produced when ATP is broken down and how is it broken down?
-When ATP is broken down it produces ADP (adenosine diphosphate + phosphate) and energy is released
-This is done through the enzyme ATPase
-Is a cyclical process
Describe what happens within the phosphocreatine system?
-High energy, short duration system
-Is anaerobic process
-ATP can be used to create phosphocreatine
-Creatine and ATP with creatine kinase can be used to produce PCr and ADP
-Creatine kinase can then also be used to convert ADP and PCr back into ATP and creatine
What is the purpose of the PCR system
-Allows us to generate energy at fast rate- more creatine= more PCr in muscles- able to generate energy more
What sports is the PCR system useful in?
-Useful in sprinting, weight lifting
How is replenishment of PCR achieved
-Replenishment is achieved through passive recovery- 30 seconds- 70% recovery
2-3 minutes- reach 98% replenishment
Describe the storage of energy within the body?
Carbohydrate metabolism
-Energy stored in adipose tissue, blood plasma, liver and skeletal muscle
-Adipose tissue- largest store-stored as triglycerides- when needed is broken down into fatty acids and glycerol
-In muscles energy is stored as IMTG and glycogen- IMTG can be broken down into fatty acids
-Glycogen also stored in liver- more emergency use- when needed is broken down into glucose
Describe what happens within glycogenolysis (glycogen breakdown)
-Requires enzyme glycogen phosphorylase
-Breaks it down into glucose 1-phosphate and glucose 6 phosphate
-These glucose phosphates are then used within glycolysis
Describe what happens in glycolysis (breakdown of glucose)?
-Is first broken down into two molecules of pyruvate (each have 3 carbon molecules)
-Generates anaerobic energy from glucose
-Occurs in cytoplasm
-ATP is required (converting glucose into glucose 6 phosphate and then to convert it again into other phosphates)
-2 ATP molecules are required which causes a production of 4 ATP molecules. Two molecules of NADH is also produced
What are the enzymes involved in glycolysis?
-Hexokinase-used to convert glucose into glucose 6 phosphate
-Phosphofructokinase-helps convert glucose 6 phosphate into pyruvate
What happens if glycolysis occurs in anaerobic conditions?
lactate dehydrogenase then convert pyruvate into lactate and hydrogen ions- removal of H ions can be sped up by light exercise (active recovery)
What happens if glycolysis occurs in aerobic conditions?
- pyruvate dehydrogenase converts pyruvate into Acetyl CoA
-Acetyl-CoA then enter Krebs cycle, citric acid cycle and the tricarboxylic acid cycle (all are the same thing)
What does the kerbs cycle result in?
results in full breakdown to CO2 and H20. Also causes release of majority of energy
What happens after the Krebs cycle in order to exert energy?
- electron transport chain is required to get energy out
-NADH and FADH2 produced in krebs cycle donate protons (H+ ions) to the electron transport chain which generates an electrical gradient across the mitochondrial membrane
-This gradient is used to generate more ATP
Describe what happens in the process of lipid metabolism?
-Fatty acids are produced from lipolysis in adipose tissue and skeletal muscle (breakdown of fatty acids)
-Requires hormone sensitive lipase to breakdown triglyceride into glycerol and fatty acids
-These fatty acids can then be used in muscles or transported to where energy is required
-HSL is inhibited by insulin
-Fatty acids released from adipose tissue travels to skeletal muscle for oxidation
-Fatty acids released from IMTG go directly to mitochondria
Describe the process of fatty acid oxidation?
-First needed to be converted into fatty acYL CoA which moves into mitochondria then beta-oxidation occurs producing acetyl CoA which gets fed into krebs cycle to [produce ATP
-fatty acYL CoA is attached to carnitine by enzyme CPT1 producing ACyl-Carnitine
-ACyl-Carnitine is broken down by CTP2 to covert it back into fatty acid and carnitine
What factors affect carbohydrate and fat oxidation in the body?
-Exercise duration
-Exercise intensity
-Exercise mode
-Gender
-Training status of individual
