Anaerobic Metabolism Flashcards
What does HLa value depend on?
Production
Removal
Turnover of HLa
Where does lactic acid occur? How?
In skeletal muscle
When NADH + H is oxidized to NAD by transfering H ion to pyruvic acid.
What do amount of HLa produced depend on?
Relative rates of glycolytic (muscle contraction)
Oxidative activity (enzyme activity)
How does muscle contraction affect amount of HLa produced?
Ca2+ release causes glycogenolysis via glycogen phosphorylase activation
How does enzyme activity cause HLa?
Increase activity of LDH leads to the production of HLa from pyruvate in exercising skeletal muscle
How does muscle fiber type affect to production of HLa?
Due to isoenzyme 4&5 and low mitochondria density
How does system nervous system produce HLa?
Heavy exercise increase epinephrine and glucagon, supress insulin, stimulating glycogenolysis -> increase pyruvate
How does insufficien oxygen produce HLa?
High intensity short duration leads to glycolysis rapid, extra H+ transferred to pyruvic acid and form HLa
How does clearance of lactate happen?
Oxidation (50-70%)
Glycogenesis (10-25)
Transamination
How does HLa get transported out and into tissues via?
Monocarboxylate transporters (MCT1-14)
Can muscle cells produce and consume HLa at the same time?
Yes. Btw cytoplasm and mitochondria
In heavy exercise, what fuel does the Heart prefer?
hLa
How does hLa reconverted to glucose in blood?
Via GNG (gluconeogenesis) in the liver
Why is slow oxygen delivered to mitochondria insufficient?
Bcs enzyme supported for aerobic oxidation is attenuated
Eg: cytochrome oxidase
What are two types of HLa shuttles?
Extracellular
Intracellular
Where does lactate get clearace?
Muscle and blood
What is extracellular clearance of lactase?
Lactate got removed from blood circulation rather than inside the cell
How does lactate in skeletal muscle got cleared?
Monocarboxylate transporters transport lactate out of muscle fibers into blood circulation
How else HLa goes clearance?
Skin excretion
What is intracellular HLa shuttle?
Lactate is transfer from cytoplasm into slow oxidative mitochondria via monocarboxylare transporter.
What happen to lactate inside the mitochondria?
Lactate is reduced to pyruvate, which will be used for energy
How to measure anaerobic metabolism?
Atp-pc and lactate
Where to measure anaerobic metabolism in atp-pc? Where in lactate?
In muscle. Difficult to measure
Blood
During exercise, how many minute to equilibrate btw muscle and blood hla lvls?
5-10 minutes
Prior excercise, how is muscle Hla compared to blood HLa?
Higher
What is property for atp-pc energy system?
High power low capacity
Energy output 72kcal/min sustain for 9-10 sec
What is property for anaerobic glycolysis energy system?
Equal power equal capacity
36kcal in 1 min 20s
Property for aerobic energy sstem?
Low power, high capacity
9cal/min sustain more than 2hrs
Tests for anaerobic power and capacity?
Wingate test
Margaria-kalamen stair climb
Field test
What is EPOC?
Excess postexercise oxygen consumption - oxygen consumption during recovery is above normal resting value
During the exercise, how te energy is supplied?
Oxygen transport and utilization
Utilization of oxygen stores in capillary blood and myoglobin
Splitting of stored atp-pc
Anaerobic glycolysis
What is steady state?
If intensity is low enough, oxygen supply will equal demand
How much time for 50% atp-pc restored? Full restore
30 seconds
2 minutes
How many percent of epoc to restore oxygen stores?
2-3%
How many % to recover HR and breathing rate?
1-2%
What are the causes of epoc?
Restoration of o oxygen Restoration of atp-pc Elevated cardio-vascular respiratory function Elevated hormone Elevated body temperature Lactate removal
What are the most important cause of epoc?
Elevated body temperature. Each celcius = 13-15% increase metabolism
How many % of epoc does elevated body temp tak3?
60-80%
What is the minimal contributor to epoc?
Lactate removal
In short distance, what energy dominate? What is its hLa lvls?
Anaerobic and high
In long distance, what energy dominate? What is it hLa?
Aerobic less Hla
How is H+ a problematic?
h+ accumulation stimulate pain via nerve endings in skeletal muscle
How does H+ decrease performance?
Metabolic fatigue - reduce atp production due to enzyme change
Change in muscle membrane transport
Glycogen breakdown slowed by inactivation of glycogen phosphorylase via H+, PC breakdown high limit atp production
How does lactic acid cause muscle fatigue?
Interferece of H+ with uptake of Ca necessay for excitation-contraction couplig and relax of cross bridge in muscle fibers
