• Energy we use 
• Adenosine TriPhosphate
• Each molecule has 3 phosphate
• 20 seconds you can hold your breath (aka body stores only that much)

• Cretin Phosphate
• Used to bulk up
• Cretin + ATP last 4 times as muc as ATP just by itself
• Not raw form - gets turned into ATP

Metabolism with O2
Not all metabolism produces energy, some consumes as well. 

When metabolism without O2
Ex. Swimming and you hold your breath
 - price in body: lactic acid buildup that can produce pain
- pain needed to bulk up muscles
- very dangerous when it reaches lactic acid limits

produces energy
- traditional sense

• needs energy
• does not produce energy
• uses energy to replenish skin cells/hair/etc.

Keep using CP you may disrupt body's ability to produce CP 

Metabolism supplies this energy

Our body uses energy. Units: Calories