March 16, 2012
Energy Supply in Exercise
- For a 10 second sprint, all energy reserve is in the muscle. They
have creatinine, phosphates, dissolved O , a2d PO . 4
- From 10-60 sec, there is anaerobic metabolism (glycolysis) and
lactate is produced. Lactate makes irritability and causes you to
- Greater than 60 sec requires aerobic metabolism (O ). N2ed
oxygen delivery (crucial) for sustained exercise.
Anaerobic: Glucose 2 ATP + 2 Pyruvate + 2 lactate
Aerobic: Glucose 2 pyruvate TCA cycle and oxidative
phosphorylation 36 ATP + 6CO + 6H 2 2
Mammals and birds have the most efficient aerobic respiration. Can
have more sustained movements.
A T-Rex could have a huge burst of anaerobic activity, but after that,
these cold-blooded reptiles would deplete their energy store.
o Mammals have a left and right heart with 4 chambers in total.
Have a low pressure on the right side of the lung to have delicate
lungs to have rapid gas exchange.
o Bird flu is deadly because cannot afford and pulmonary infections
since it is 1 tube that acts as the lungs for the blood gas
Aerobic Work Capacity:
V(dot = over time)O Ma2: Units (L/min), Significance (Capacity). More
consumption of oxygen is based on body mass! Even a small person that
is really fit, it does not matter if compared to a large person they may
not be as fit.
But to normalize for comparison of different body size (mL/min/kg), to
see that a small fit person will have more V(dot)O Ma2.
Males tend to have a higher hemoglobin per body weight, so they have a
higher V(dot)O M2x.
Can sustain 50% V(dot)O Max2approximately 4 hours/day.
A lower resting heart rate can determine the longevity of the species.
Humans lives > mice since the resting heart rate mouse > human.
If trained, can sustain more of the maximum capacity.
Can sustain 70% VO Max for 10 min-2 hours (depends on level of
> 70% VO2 Max can be sustained for ~2-5min (depends on fitness
If you are deconditioned, you can increase your capacitance, but if you
are slightly active, you won’t increase your fitness capacitance much
more. It is related to the body size. Unless REALLY unactive, you won’t
gain more than 10-25%.
A heart attack will drop your capacity, so < 50% VO2 Max will become >
70% VO2 Max.
Volume of O2 (mL) per minute per Kg (VO Max): 2
- Resting O consumption would be around ~250 mL/min/kg for a 70