There is a major risk of doing harm by spraining or straining something by doing speed work now. Low-intensity workouts will keep you fit and mentally stimulated right up to the starting cannon. Try to get eight hours' sleep each night starting March 6. Most of us just do not get enough sleep. Friday night stomach butterflies may inhibit a good night's sleep before the race.
Food is a major concern for runners.
I recommend going vegetarian for the final four days. Meat takes longer to digest. A steak eaten on Friday night might just sit like a rock in the gut the next morning. Extra servings of salads make for a better chance of a good bathroom experience in the final hours before the race. Whole-grain breads and yogurt are ways to insure tasty nutritious meals and snacks for those final four days before the race.