I remember my first Nutrition course I took in college. I was surrounded by a room full of nurses. Little did I know the depths of the journey that I was about to embark on. That was over ten years ago, and if I can offer one tip it is this:
Eat the Rainbow.
Your body is a miraculous symphony of chemical reactions. The foodstuffs you digest impact all areas of your life. Choose wisely.
Keep in mind that you cannot "out exercise" a poor diet. Your body needs micronutrients to perform optimally. It is okay to enjoy your favorite treats...in moderation. Just try to get as close to clean eating as you can, and you just might find that energy to get your movement in.