Chapter 3 (Energy systems)

for sports nutrition

What do all systems use?

chemical energy for ATP!

What is ATP used for?

main energy source in body!

ATP-PC (creatine phosphate)

phosphocreatine stored in muscle; very short duration and high intensity exercises

ATP-PC process?

CP splits into → creatine + phosphate. Phosphate goes to ADP → ATP for energy

Creatine recharges during aerobic metabolism

ATP donates phosphate to creatine → CP reforms

In a nutshell, ATP-PC is

CP drains during high energy exercise. Recharges w/ATP during metabolism. Happens in mitochondria.

Anaerobic Glycolysis’s fuel source?

Carbs (glucose/glycogen)

Anaerobic glycolysis supports what duration of activity?

Short (10-120) and fast speed.

Anaerobic glycolysis process?

Carbs → pyruvate → product: lactic acid/lactate.

What analogy works best for Anerobic glycolysis?

Muscles make lactate when oxygen low. Fuel for body during anaerobic exercise!

ATP-PC’s rate of ATP production? and for what kind of exercise?

very small and very fast action

What’s glycolysis and enzyme used?

Break down glucose w/o oxygen to rephosphorylate ADP → ATP. Enzyme: PFK (phosphosfrutokinase)

PFK enzyme controls ___ and is activated when

glycolysis speed; when cell’s energy is low.

Oxidative Phosphorylation

Fuel source: carbs + fats. For long and slow activities.

For oxidative phosphorylation, ______. Lower intensity = ____

higher intensity = more carbs; more fat

What is oxidative phosphorylation’s rate of ATP production?

large amount!

ATP - muscle process?

ATP breaks down → ADP forms → energy releases for contraction

ATP used → regenerates

Carbs’ fuel utilization?

30 ATP

Fats’ fuel utilization?

113 ATP

What is Respiratory Exchange Ratio?

CO2 - O2 ratio used during metabolism. Chooses what fuel to use for energy?

How to interpret respiratory exchange ratio?

1 = 100% carbs (high activity)

0.85 = 50/50 carbs and fat (low/endurance)

0.7 = 100% fat

what does lactate NOT do and is NOT?

cause muscle fatigue; waste product

Lactate with oxygen becomes what?

pyruvate!

Where can lactate travel?

liver/heart/kidney for energy source (think highly aerobic tissue)

Oxidative system…

slowest ATP production, largest capacity

Creatine’s diet source is ____ and is synthesized in ____

meat/fish; liver