Week 2 - Exercise Metabolism Pt.1 Flashcards
Describe bioenergetics
Bioenergetics involves the flow and exchange of energy within a living system, including the conversion of food into usable energy for cell work, with implications for performance
Define metabolism
Metabolism refers to the sum of all chemical reactions that occur in the body, including anabolic reactions for synthesis and catabolic reactions for breakdown of molecules
How do enzymes influence chemical reactions in the body
Enzymes are proteins that lower the activation energy and accelerate chemical reactions, thereby increasing the rate of product formation
Describe the process of oxidation-reduction reactions
Oxidation involves removing an electron (adding oxygen), while reduction involves adding an electron (removing oxygen), and these reactions are always coupled
What are the key characteristics of anaerobic pathways for ATP production
Oxygen Independent & Occurs in Cytosol
Substrate level phosphorylation (PCr system)
Most rapid and simplest method of producing ATP
Depleted after 10-15 seconds of maximal effort
Anaerobic glycolysis
§ Increased in by-products of ATP breakdown activates energy flux through reactions of the glycolytic pathway
Capacity is three-hold higher (30-90 secs) than PCr system
Net gain of glucose is 2 ATP molecules, Net gain of glycogen is 3 ATP, as it does not require phosphorylation by ATP
Explain the significance of the Citric Acid Cycle in aerobic ATP production
The Citric Acid Cycle generates high-energy electrons (NADH, FADH2), and ATP molecules through a series of reactions that occur in the mitochondria
How does temperature and pH influence enzyme activity
Temperature and pH can affect enzyme activity, with extremes leading to denaturation, impacting lactate threshold, H+ concentrtion, pH levels and ATP production
What are the classifications of enzymes
Kinases (add phosphate group)
Dehydrogenases (remove H atoms)
Oxidases (catalyse oxidation-reduction reactions involving oxygen)
isomerases (rearrangement of molecule)
Describe the role of coupled reactions in cellular chemical reactions
Coupled reactions involve the liberation of energy in an exergonic reaction to drive an endergonic reaction, ensuring energy transfer and balance within the cell
Describe the process of oxidative phosphorylation in mitochondria
Electrons are passed down a series of electron carriers, coupled with the pumping of H+ into the intermembrane space. Increased concentration of H+ ions in the intermembrane space leads to movement of H+ through ATP synthase, producing ATP. O2 is needed to accept these electrons to form H2O.
Define EPOC in exercise physiology
Exercise post-exercise oxygen consumption refers to the elevated oxygen uptake above rest during recovery from exercise. The magnitude and duration of EPOC are influenced by the intensity of the preceding exercise
How does energy systems change when influenced by exercise
High Intensity: ATP-PC system (<5s)
Intense Exercise: Anaerobic Glycolysis (>5s)
HIIT: 50% Anaerobic & Aerobic (>45s)
Prolonged Exercise: Aerobic (>10mins)
Define oxygen deficit
Discrepancy between initial demand and oxygen consumption
List some aerobic bioenergetic capacity adaptations endurance trained individuals have developed
Greater regional blood flow
Increased cellular adaptation and efficiency
Increased mitochondrial volume in muscle fibres results in less lactate production at beginning of exercise
What are some slow and fast components of EPOC
Fast: resynthesis of stored PC, muscle and blood O2 stores
Slow: Elevated HR and breathing, increased body temperature, elevated blood levels, conversion of lactic acid to glucose
