ch 11 Flashcards
energy definition
ability to perform work
power output
rate that muscles can produce energy
Anaerobic (no oxygen): The Phosphagen system
immediate energy system
breaks down energy stored in muscles
There is a lot more creatine phosphate– approx 5x more, (breaks down super quickly) than ATP in our muscles
Other names for the phosphagen system
Alactate
ATP-PC
After all out power for 10 sec
ATP is mostly used
–> 40% left
peak power/strength power
mainly using stored ATP
sustained power
high power outputs for several seconds
CP stores are used
Anaerobic: The Glycotic System
can produce lactate
uses glucose/glycogen as fuel
Other name for glycotic system
Anaerobic glycolysis
Normal amount of glucose in blood
3.3-7g
If we use the glucose in our blood we can generate
2 ATP
If we use glycogen stores in muscles we can produce
3 ATP
Difference between glycotic system and phosphogenic system
phosphogenic= faster energy
Glycotic= can produce more energy, still fast energy
How long can high rates of ATP production by glycolysis be sustained
60-90 sec
Local muscle fatigue is the result of exhausting which pathway?
glycotic system
-low muscle pH: H+ concentration and lactate formation, acidity
Aerobic: The Oxidative Sytem
-primary source of ATP when at rest, low intensity activities, and activities longer than 2-3 min
-can use proteins, carbs and fat
-lower intensity= lower power
Other names for the oxidative system
aerobic system, krebs cycle
Oxidative system: where are enzymes for aerobic ATP production found?
the mitochondria
Aerobic Carbohydrate breakdown
Glycolysis: 3 main processes
- Glycolysis
- Krebs cycle
- Electron transport chain
aerobic generates much more ATP but slower
Aerobic ATP yield
36-40 ATP
Anaerobic ATP yield
2 or 3
Oxidative system: macronutrient energy breakdown
Fat: 1g= 9 kcal
Carbs: 1g= 4 kcal
Protein: 1g= 4kcal
fat-ideal way to store energy bc doesn’t hold on to water
Oxidation of fat: Aerobic Lipolysis
fatty acids are released from adipose tissue to make ATP
Approx fuel reserves stored in fat in avg M or F
70,000 to 75,000 kcal
Carb vs fat ATP generated
carbs= 6.3 ATP per molecule
fat= 5.6 ATP
Protein metabolism
low carb stores= won’t be able to generate energy (protein metab is not ideal)
amino acids broken down via deamination, krebs cycle
products: CO2, H2O, urea (toxic), ammonia, and some ATP
100m sprint uses
glycolytic system??
What determines which energy system is used?
Power/intensity
–> time alone does not matter
Do we only use one energy system at a time?
NO
different percentages of each but usually all systems are contributing
Why is there a difference between metabolic power and mechanical power?
due to the muscle’s efficiency at converting fuel to force
Why is warmup important in terms of oxygen and aerobic exercise?
we want to oxygen deficit to occur at the beginning of the warmup NOT the exercise
–> there will always be oxygen deficit in the beginning no matter what the intensity is
bc homeostasis disrupted
EPOC
excess post-exercise oxygen consumption
-resp. rate decrease
-then HR decrease
-still excess oxygen as they come down
Factors that cause EPOC
In rapid recovery phase: ATP and CP are replenishing as well as O2
Elevated body temp for longer= longer EPOC
Residual hormones epinephrine and thyroxine increase metab
HR and resp rate still elevated= extra O2 needed
Steady state aerobic and V intense work for short time:
What is recovery time?
recovery is rapid.
v little muscle acidity and lactate accumulation
no significant body temp elevation= very small EPOC
How does active recovery help muscle acidity levels?
speeds up rate of blood flow in muscle=> normalizes muscle acidity faster
What are 3 things fatigue influenced by?
CNS and PNS fatigue
damage to muscle and connective tissues
psychological factors
Would a 2 hour walk or 60 burpees take longer to recover from?
burpees
more intense, shorter time= higher power
more lactate buildup
blood lactate levels
VT1 and LT1= lactate/ventillary threshold 1 (steady state)
60-90min
fail talk test
VT2 and LT2= not able to maintain for very long,
H+ ions interfere w ATP being produced: muscle fatigue
blood lactate accumulation
Whys is there no % VO2 max for VT1/LT1 or VT2/LT2?
different for everyone
changes w training
–> genetics (slow/fast twitch fibres)
–> specific local adaptation: better at removing H+ to decrease lactate levels!
Does endurance training reduce lactate production?
NO
your body gets better at removing lactate and liver converting it to blood glucose
Fatigue
inability to maintain exercise intensity
Running below LT1, fatigue occurs due to?
mental fatigue (bored), mechanical stress (foot strikes), glycogen depletion
What is a good level to run a long distance race?
slightly above LT1
Close to LT2, fatigue is due to?
inability to continue buffering H+ at given rate
Above LT2, fatigue occurs due to?
high muscle acidity
Does blood lactate cause fatigue or DOMS?
NO
CNS fatigue
neurotransmitters get depleted during strenuous exercise
reduces performance, motivation, motor control and memory
When is Nervous system fatigue likely to occur?
v strenuous exercise close to upper limit of muscles ability to produce force (high power activities)
CNS fatigue signs
overall body/systemic energy deprivation
PNS fatigue signs
local, muscle-specific incapacity to do work
nerves control
muscle contraction number, sequence and force
–> nervous system chooses which muscles get “shut off”
Which energy syst has most capacity for ATP production
oxidative system
Long jump energy syst
phosphagen
run as hard as you can for 10 min, which is the main energy syst?
oxidative
