Do you know what you plan to wear for the race? We’ve had temperature swings from bone-chilling to springish this week alone, so you should keep a lot of options in mind. Think about what kind of food you’ll want to eat, as well as fluids and gels. I always wore a different pair of shoes and socks around Hopkinton, then changed into my racing footwear before the race. I also brought extra pins for my number, and an old marathon mylar sheet to lounge on in case the ground was wet. And of course, my iPod (which I never wore during the race.)
What, for you, is essential in your race bag?