KIN 100 1st Edition Lecture 4 Metabolism Sources of energy Immediate energy source in the muscles Short term glucose long term fat stores Anaerobic metabolism energy creation without O2 Immediate in muscle fibers ATP adenosine triphosphate CP creatine phosphate Using ATP Third phosphate is released from molecule and releases energy ATP ADP P heat energy Using CP CP ADP ATP Creatine creatine kinase CK enzyme that helps with reaction reaction takes ADP from ATP reaction above Short term glycolysis goal make ATP from glucose most glucose is stored as glycogen glycogenolysis conversion of glycogen to glucose glucose is broken into 2 pyruvate molecules and ATP pyruvate can be converted to ATP pyruvate can be converted to lactate which can be converted to ATP Lactate lactate hydrogen ion H lactic acid lactic acid impairs muscle contraction acidosis muscles become too acidic good energy source Lactic acid shuffle slow twitch fibers use energy from lactic acid made by fast twitch fibers glucose paradox glycogen supply is limiting liver has lots of glycogen but prefers to make glucose from lactic acid why not use glucose no negative side effects glycolysis release only 5 of the total energy in glucose Oxidative Metabolism creates more ATP Krebs Cycle Pyruvate acetyl CoA hydrogen hydrogen is oxidized for more energy occurs in mitochondria requires oxygen Acetyl CoA Vitamin B derivative Electron Transport Chain ETC uses by products of Krebs Cycle occurs in mitochondria by products H2O CO2 Heat Summary O2 glucose ATP CO2 H2O heat 1 glucose molecule 38 ATP 4 Krebs 34 ETC Fat Metabolism Adipose Tissue fat cells adipocytes largely subcutaneous tissue composed of triglycerides triglyceride glycerol 3 free fatty acids FFA Beta oxidation uses FFA FFA acetyl CoA Krebs or ETC generation of oxygen carriers from FFA facilitated by epinephrine caffeine yields 460 ATP Energy From Protein contains nitrogen deamination removal of N2 results in creation of metabolites pyruvate pyruvate enters Krebs Cycle Nuclear Magnetic Resonance Spectroscopy NMR non invasive way to measure phosphorus carbon etc Distance Time hours Aerobic Anaerobic 100m 10 s 400m 45s 1500m 3 30 min 5000m 15 min marathon 2 1 99 15 85 50 50 80 20 99 1
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