Summary Pien's aantekeningen

A snapshot of the summary - Pien's aantekeningen

• 1 Nutrition and Sports

• 1.1 1. Energy metabolism

• For very high force contractions lasting 1-2 seconds, the initial energy source is from:
  a. Glycolysis
  b. Creatine phosphorylation
  c. ATP stores
  d. None of the above

  C. ATP stores
• After what period of time does maximal dynamic exercise become predominantly aerobic?
  a. 10 sec
  b. 30 sec
  c. 4 min
  d. 10 min

  C. 4 min
• What are the 3 energy systems for ATP resynthesis?

  1. Phosphocreatine (PCr):
     
  1. rate: 4.4 mol/min
  2. delay: instantaneous
  3. capacity: 0.67 mol
  2. Anaerobic glycolysis:
  1. rate: 2.3
  2. delay: 5-10 sec
  3. capacity: 1.6 (6.7) mol
  3. Oxidative metabolism:
  1. Glycogen:
  1. rate: 1.0 mol/min
  2. delay: minutes
  3. 84 mol
  2. Blood-borne glucose
  1. rate: 0.34
  2. delay: ~90 min
  3. capacity: 19
  3. Lipids
  1. rate: 0.40
  2. delay: >2 hr
  3. capacity: 4000 mol
• If you have the anaerobic metabolism, which 2 systems are at work then?

  - phosphagen system:
  

  • ATP
  • phosphocreatine breakdown

  - glycolytic system
• How does the phosphocreatine (PCr) breakdown work?

  • Activation:
    
  • decrease ratio ATP/ADP because of ATP breakdown
  • Inhibition:
  • increase ratio ATP/ADP due to increased aerobic ATP production of decreased ATP utilization
• The complete resynthesis of PCr after very high intensity exercise normally takes:
  a. 10 sec
  b. 30 sec
  c. 1 min
  d. 4 min
  e. More than 10 min

  D. 4 min
• PCr resynthesis during recovery from exercise is inhibited by:
  a. An excess of creatine
  b. Hyperventilation
  c. An excess of oxygen
  d. A lack of oxygen
  e. Submaximal muscle contractions

  D. A lack of oxygen
  So, oxygen is needed for resynthesis!
• The average intensity of exercise (%VO2max) for an elite middle distance runner during a 1500 m race will be about..
  a. 80%
  b. 100%
  c. 120%
  d. 200%
  e. 300%

  C. 120%
• The net production of ATP by substrate level phosphorylation in glycolysis is
  a. 2 from blood glucose and 3 from glycogen
  b. 2 from blood glucose and4 from glycogen
  c. 3 from blood glucose and 4 from glycocen

  a. 2 from blood glucose and 3 from glycogen
• Musle and liver glycogen stores in a well nourished athlete would be sufficient to sustain approx how many minutes of submaximal exercise (if this were the only energy source used)? The exercise is clublevel marathon pace.
  a. 30 min
  b. 90 min
  c. 120 min
  d. 180 min
  e. 300 min

  B and C