What you have eaten recently is important in determining how much energy you have from the atp-cp system?

yes

Explanation:

What you consume determines how much energy you will have from system. Creatine Phosphate which is stored in the muscles just like the ATP and can be broken down in absence of oxygen without forming lactic acid and providing large amounts of energy.

Taking carbohydrates provides enough energy. They are broken down faster compared to lipids and proteins.