Exercise Flashcards
what is the most variable component of energy balance (not the largest)?
exercise
What is used as energy for muscle contraction?
ATP, phosphocreatine (PCr), and glucose
why is ATP not good to store?
being broken down very quickly (roughly about 2-4 secs)
how long does phosphocreatine (PCr) last?
10 sec - 1 min
what is going on when muscle is at rest?
PCr concentration is about five times greater than ATP concentration
What is going on during active muscle?
PCr concentration falls as much of it is used to restore ATP concentration from the ADP that builds up. The PCr concentration does not fall to zero because some resynthesis occurs even in active muscles
how long does anaerobic glucose last?
30 seconds to 2 minutes of intense exercise
What is disadvantages of anaerobic glucose?
not sustainable but fast; only derive 5% of potential energy from glucose; lactate accumulation, acidity, fatigue (glycolysis –> pyruvate –> lactate)
what is aerobic glucose used for?
moderate-low intensity
does aerobic or anaerobic produce more ATP?
aerobic, but slowly
how long is aerobic glucose sustainable?
2 minutes to 4-5 hours
What are the exercise fuels?
glycogen, fat, protein, oxygen supply
what is the primary source of energy?
glycogen
what is a minor source of energy?
protein
What is the main fuel for long, low intensity exercise?
fat
Where is glycogen stored?
in liver and muscle
What is glycogen important for?
to maintain blood glucose levels (dietary CHO)
Training can improve what?
use of fatty acids
What is the oxygen supply important for in exercise fuels?
circulation and oxygen carrying capacity of blood
as you increase exercise intensitiy, the proportion of used (increase/decrease) and the proportion of carbohydrates used (increase/decrease)
decrease; increase