Transcription of RESPIRATORY EXCHANGE RATIO
1 RESPIRATORY EXCHANGE RATIORER = VCO2/VO2 Oxidation of a molecule of Carbohydrate6 O2 + C6H12O6 6 CO2 + 6 H2O + 38 ATPRER = VCO2/VO2 = 6 CO2/6 O2 = of a molecule of Fatty Acid23 O2 + C16H32O2 16 CO2 + 16 H2O + 129 ATPRER = VCO2/VO2 = 16 CO2/23 O2 = that I know how to calculate R, what doesthis mean to me?1. You can determine what fuel is being used for energyproduction2. You can calculate energy expenditure for a given activityREnergy Expenditurekcal/L example, if I am exercising and consuming L of O2/min and my Rvalue is I will be expending kcal/min ( L of O2 x kcal/ O2= kcal/min).
2 Thus, if I exercise for 30 min I will burn 292 however, I exercise at a lower intensity and my oxygen consumption is with an R of , I will burn only kcal/min ( L of O2 x O2 = kcal/min). Thus, if I exercise for 30 min I will burn TABLE on Page 144 Energy ExpenditureExcess Post-Exercise Oxygen Consumption(EPOC)Due to:1. Replenishing of the ATP/CrP stores2. Increased levels of catecholamines in the blood3. elevated rates of fatty acid oxidation4. increased body temperature5. continued substrate cyclingMaximal Oxygen Uptake (VO2max)1. Regarded as the best measurement of aerobic capacity2. Refers to the maximum volume of oxygen that can beconsumed per minute and used for aerobic energy production3.
3 Linear relationship between VO2max and exercise intensityLactate Threshold1. Single best predictor of aerobic ( , endurance) Usually expressed as % VO2max3. Aerobically trained individuals typically have a lactatethreshold that is greater than that of untrained. This is a result ofthe aerobically trained athletes having a more developed ability togenerate energy aerobically and results in less lactate : 50-60% VO2maxTR: 70-80% VO2maxCAUSES OF FATIGUE1. Short duration, high intensity exercisea. CrP depletionb. Metabolic By-products1. Increased lactate concentration [HLa], whichincreases [H+].a. Decreased pHb. Decreased rate of glycolysisc.
4 Interferes with Ca2+ binding to troponin2. Prolonged endurance exercisea. Glycogen depletion1. Muscle glycogen levelsa. Muscle glycogen declines throughout exerciseb. As muscle glycogen levels decline, there is anincreased reliance on blood glucose2. Liver glycogen levelsa. Liver glycogenolysis attempts to maintainblood glucose levelsb. When liver glycogen levels fall and the rate ofliver glycogenolysis is less than the rate ofmuscle glucose uptake the blood glucoseconcentration declinesc. Time to fatigue due to an inability to providean adequate supply of carbohydrate to themuscl
