I am gradually working on optimizing my diet for performance. Generally I eat very healthy, mostly vegetarian, with occasional salmon or tuna. A rule of thumb that I attempt to go by as much as possible is 'if it does not occur in nature, don't eat it'. That means I eat a lot of fruit, vegetables, whole grains, beans, nuts, seeds, plain yogurt, egg whites. My daily caloric intake during base training period (right now) is usually 2000-3000 depending on how long the day's workout was. During the summer when I do high volume training, my daily calories are more like 3500-4000.
This is a typical weekday for me:
Breakfast (7 am) - 3 egg whites, 1/2 cup oatmeal (measured dry) with flax meal and wheat germ, small glass of orange juice
Morning Snack (10 am) - piece of fruit
Lunch (noon) - Hummus, spinach, sprouts, avocado sandwich on whole wheat, piece of fruit
Afternoon Snack (3pm)- handful of almonds and dried apricots, Clif Bar (post-workout)
Dinner (6:30pm)- sliced tofu fried in Indian spices and olive oil, steamed kale, sweet potato (plain)
Evening Snack - (9 pm) air-popped popcorn (plain or with brewer's yeast), decaf green tea
I am reading a book now on how to be a vegan and an endurance athlete - Thrive by Brendan Brazier. This is a great book and I would recommend that all athletes interested in nutrition read what Brendan has to say (look at www.brendanbrazier.com to get started). I saw Brendan speak at last year's Vancouver Marathon expo where he demostrated making homemade vegan energy bars. A main point he makes is that to enhance daily recovery, it is important to choose foods that do not create further stress within the body. It is important to choose foods that create an alkaline state within the body since hard exercise makes the body acidic.