Exercise Metabolism Flashcards
capacity of atp generation for glycolytic system
190-300 mmol atp/dry muscle
capacity of atp generation for the phosphagen system
55-95 mmol atp/ kg dry muscle
power difference for capacity of atp between glycolytic system and phosphagen system
4.5 vs 9 mmol atp/ kg dry muscle
what influences pcr resynthesis
blood flow and oxygen delivery (H ion removal)
aerobic fitness
what causes a decrease in power output during all out exercise
depletion of pcr (glycolysis and aerobic metabolism can’t compensate)
How do pcr stores recover
biphasic processs, rapid initially recover followed by slower second phase
typical carbohydrate stores for 70kg man
blood glucose 3-5g
liver glycogen 80-100g
muscle glycogen 300-400g
1500-2000kcal (6000-8000 joules) total
typical fat stores for 70kg man
adipose tissue 3.5-14kg
muscle triglyceride 200-500g
approx 31500-126000 kcal for 70kg man with body 5-20%
Substrate utilisation depends on
exercise intensity and duration
training status
diet and substrate availability
temp/altitude etc
glucose oxidation
C6H12O6 + 6O2 = 6CO2 + 6H2O
Fat Oxidation (palmitate)
C16H32O2 + 23O2 = 16CO2 + 16H2O
what does pyruvate dehydrogenase do
key regulator of oxidative glucose metabolism, key in matching oxidative glucose metabolism to atp demands of muscle contraction, intensity increase so does pdh activity
unlike phosphorylase that even at low intensity is sufficient to allow maximal muscle glycogen breakdown
effect of exercise intensity on blood glucose
intensity increases so does blood glucose concentration as hepatic glucose production increases
What limits fat oxidation
are the of lipolysis
transport of fatty acids in blood
uptake of fatty acids by muscle
transport across mitochondrial membranes (availability of carnitine)
process of beta oxidation
oxygen availability for mitochondrial oxidation
