chapitre 3 Flashcards
The direct source of energy for force production
by muscle is
ATP
T/F: Creatine supplements result in immediate
increases in strength, speed, and power.
False
T/F: Lactate is a metabolic waste product that causes fatigue.
false, Lactate is an important metabolic product
that can be used by other cells as a source of
energy; the liver can use lactate to make glu-
cose. The accumulation of lactate molecules
does not cause fatigue; one likely cause is the
metabolic acidosis that is associated with high-
intensity exercise when glycolysis is used at a
high rate.
At rest and during low levels of physical activity,
what is the preferred source of fuel for the aerobic energy system.
fat
ATP to ADP is an _ reaction
exergonic
The process of
rephosphorylation of ATP from ADP, therefore, is an_ reaction;
endergonic reaction
do energy release from the break of the bond of creatine phosphate is use to power muscle contraction
no, the energy is used to phosphorylate ADP into ATP
role of creatine phosphate stored in muscle
acts as a readily
accessible reservoir of energy for the re-formation of ATP.
where can creatine can be synthesized if it not consumed
liver and kidney
what are the characteristic of CPr energy system
Very fast reaction
*One ATP per CrP molecule
*5- to 10-second duration
*Anaerobic
*Fatigue associated with CrP depletion
*Predominant energy system in very high-intensity
exercise, for example, “power” event
does CPr required energy to replenish ATP
no
why does athlete breath hard for a minute after short-duration, high intensity exercise
Because the body uses the aerobic energy system to restore creatine phosphateit must temporarily
increase oxygen intake and aerobic metabolism to meet
the increased aerobic task of restoring creatine to creatine phosphate
depletion of creatine phosphate is associated with
muscle fatigue
explain creatine shuttle (see note)
Creatine that remains from chemically splitting cre-
atine phosphate is phosphorylated using energy from ATP pro-
duced aerobically in the mitochondria of the muscle. This process
requires an increase in aerobic metabolism (oxidative phosphory-
lation) and returns creatine phosphate concentrations to normal
within a minute or two.
what is the final product of anaerobic glycolysis
lactic acid
in glycolysis what happen if PFK increase and what happen if PFK decrease
increase: reaction speed up
decrease: reaction slow down
The rate-limiting enzyme for glycolysis is
PFK
do glycolysis need oxygen to replenish ATP
no
during glycolysis, exercising muscle will preferrer to use stored glycogen or glucose for energy
stored glycogen because the energy yield is higher
glycolysis is the preferred system to supply energy during which type of exercise
high-intensity
or repeated exercise lasting approximately
1 to 2 minutes
what is a difference between glycolysis and CPr system in the limitation of energy depletion
The body has a considerable amount of carbohydrate energy in the form of blood glucose and
muscle glycogen, so unlike the creatine phosphate system, the anaerobic glycolytic energy system is rarely
limited by depleted energy stores.
what does anaerobic glycolysis utilize as it only fuel source
carbs
which system become predominant when the CPr system reach its limit
anaerobic glycolysis
how many ATP is produced from glucose and glycogen during glycolysis
glucose: 2
glycogen: 3
with anaerobic glycolysis, fatigue is associated with what why
decreased pH (metabolic acidosis), because PHK decrease in acidosis environment
T/F pyruvate can only be metabolized aerobically
F it can be metabolized anaerobically and aerobically
The major advantages of the anaerobic glycolysis
energy system are
- fast ATP production, reliance upon a fuel source that is present in large amount, potential usefulness of lactate (by product)
The major disadvantage of anareobic glycolysis is the relatively
- short duration due to metabolic acidosis
what are the 3 phases of oxidative phosphorylation energy system
- carbs, fats,protein are prepared to be metabolized aerobically
- kreb cycle
- ETC
what must transported into mitchodondria for oxidative phosphorylation to proceed
pyruvate
what is the major function of kerb cycle in the oxidative phosphorylation
to oxidize, or
remove, electrons from the compounds going through
the cycle for later use in the electron transport chain
how many step is there in the krebs cycle
10
what is the rate-liming enzyme for the ETC
COX
what is the predominant system at rest and during low to moderate intensity exercise
oxidative phosphorylation
how munch ATP is created by oxidative phosphorylation and is it aerobic or anaerobic
30 via glucose, 31 via glycogen
aerobic
what does transmination and deamination mean
transmination: nitrogen group are being transferred to another compound
deamination: nitrogen group are removed completely
which one between protein, carbs or fat are the least preferred as a fuel source
protein
when does protein can compose a larger percentage of the fuel utilization
Under metabolically stressful conditions, such as starvation or exercise in a glycogen-depleted state but rarely exceed 10% of total energy production
as activity increase which fuel source is more dominant
carbs
At fairly modest levels of physical
activity or exercise, such as walking at a moderate pace,
the mixture of fuels is about
50 percent from fats and
50 percent from carbohydrates.
The proportion of energy coming from
carbohydrates and fats can be estimated accurately by use of the
RER
what is RER
a ratio of the amount of carbon dioxide produced to
the amount of oxygen consumed
RER= VCO2/VO2
RER = _ if only carb is being metabolized for energy
1.0
The fed (absorptive) state refers to the _ hour
period after food is eaten
3-4 h
The process of resynthesizing adenosine
triphosphate (ATP) from adenosine diphosphate
(ADP) is called
rephosphorylation
which of the following is a true statement
regarding creatine supplementation?
a. It has been shown to be beneficial for both strength and endurance athletes.
b. It has a direct effect on improving strength, speed, and power for strength athletes.
c. It causes dehydration and muscle cramping in strength athletes.
d. It allows strength and power athletes to sustain high-intensity training.
d
The preferred energy source by exercising
muscle for the process of anaerobic glycolysis is:
a. glucose.
b. glycogen.
c. glycerol.
d. creatine.
b
Which of the following is true about
lactate?
a. It is a waste product that “poisons” muscle and
other tissues.
b. It is produced by muscle only during high-
intensity exercise.
c. There is no lactate in blood at rest.
d. It is metabolized easily by other highly aerobic
tissues in the body for energy.
d
Aerobic production of ATP can occur:
a. in the mitochondria in a process called
glycolysis.
b. in the mitochondria in a process called
oxidative phosphorylation
c. in the mitochondria in a process called the Cori
cycle.
d. in the cytoplasm/sarcoplasm of the muscle cell
in a process called glycolysis.
b
How does the amount of ATP produced
from the breakdown of one molecule of carbohy-
drate compare to the breakdown of one molecule
of a fatty acid?
the amount produced is about the same
T/F the 3 systems are active at all time
T however, one
may be the predominant system, depending on the intensity and
duration of the exercise activity.
What energy system is likely to be
explain how CPr is activate
ATP concentrations in a muscle cell start
to decline, the drop in ATP and the concomitant rise in
ADP in the cell result in an increase in the activity of CK,
allowing the reaction to proceed even faster.
ratio of ATP energy produced by CPr
1:1 -> 1 ADP produce 1 ATP
when does CPr will need oxygen
the recovery of CrP from creatine depends on aerobic metabolism in the cell, in a process referred to as the Creatine
Shuttle
how can an athlete delay the effect of acidity by the anaerobic glycolysis system
by consuming bicarbonate
give example of activity where glycolysis is active
- Long sprints such as the 400-meter sprint in track
- Repeated high-intensity sprints such as the intermittent sprints by a soccer or basketball player
- Repeated high-force activities such as 10 to
15 repetitions of weight lifting - Regular, repeated intervals such as 50- to 100- meter swimming intervals
explain the concept of lactate threshold
At a certain point of exercise intensity,
however, the production of lactate exceeds its rate of removal,
and the lactate concentration continually climbs. this is where muscle fatigue occurs
The respiratory exchange ratio (RER) is a way of determining the body’s
metabolism of:a. creatine phosphate and ATP.
b. amino acids.
c. carbohydrate and fat.
d. lactate.
c
if value of RER is closer to 1.0 what does it means
carbs is more metabolized for energy
if value RER= 0.7 or lower what does it indicate
fat is being oxidized for energy because fat contained more carbon than oxygen so for complete oxidation of fat, it requires significant more energy to be consumed
how munch supplementation of creatine is neccesaire
3-5g/day with carb intake to enhance uptake
